CN102706670B - The damaged cable of temperature variation cable force monitoring and generalized displacement of support recognition methods - Google Patents

Abstract

The generalized displacement identification method of damaged cables and supports based on temperature change cable force monitoring is based on cable force monitoring. By monitoring the temperature of the cable structure and the environment temperature, it is determined whether it is necessary to update the mechanical calculation benchmark model of the cable structure. The mechanical calculation benchmark model of the temperature cable structure, on the basis of this model, the unit change matrix of the unit damage monitored quantity is calculated. It is calculated based on the approximate linear relationship between the current numerical vector of the monitored quantity and the current initial numerical vector of the monitored quantity, the unit change matrix of the monitored quantity for unit damage, the unit damage or unit generalized displacement vector, and the current nominal damage vector of the object to be evaluated The non-inferior solution of the current nominal damage vector of the evaluated object, based on which, when there is a temperature change, the generalized displacement of the support and the damaged cable can be quickly identified by using a suitable algorithm such as a multi-objective optimization algorithm.

Description

Generalized Displacement Identification Method for Damaged Cables and Supports Based on Cable Force Monitoring with Temperature Variation

technical field

Cable-stayed bridges, suspension bridges, truss structures and other structures have one thing in common, that is, they have many parts that bear tensile loads, such as cable-stayed cables, main cables, slings, tie rods, etc. , cables, or rods that only bear tensile loads are supporting components. For convenience, this method expresses this type of structure as a "cable structure". As the ambient temperature changes, the temperature of the cable structure will also change. When the temperature of the cable structure changes, when there is a generalized displacement of the support (for example, the generalized displacement of the support refers to the linear displacement of the support along the X, Y, and Z axes and The angular displacement of the support around the X, Y, and Z axes; corresponding to the generalized displacement of the support, the generalized coordinates of the support refer to the coordinates of the support about the X, Y, and Z axes and the angular coordinates of the support about the X, Y, and Z axes) When this method is based on cable force monitoring to identify the supporting system of the cable structure (referring to all load-bearing cables and all supporting rods that only bear tensile loads, for convenience, this patent refers to all supporting components of this type of structure It is collectively referred to as "cable system", but in fact the cable system not only refers to supporting cables, but also includes members that only bear tensile loads. In this method, the term "supporting cables" refers to all supporting cables and all supporting cables. The damaged cable in the member that only bears the tensile load (for the truss structure refers to the damaged member that only bears the tensile load) and the generalized displacement of the support, which belongs to the field of health monitoring of engineering structures.

Background technique

The damage of supporting cables and the generalized displacement of the support are a major threat to the safety of the cable structure. It is a very potential method to identify the generalized displacement of the support and the damaged cables in the cable system of the cable structure based on structural health monitoring technology. . When the bearing is displaced, or the health state of the cable system changes (such as damage), or when the two situations occur at the same time, it will cause changes in the measurable parameters of the structure, such as changes in the cable force, which will affect The deformation or strain of the cable structure will affect the shape or spatial coordinates of the cable structure, and will cause changes in the angular coordinates of any imaginary straight line passing through each point of the cable structure (for example, any one of the tangent planes at any point on the surface of the structure passes through the The change of the angular coordinate of the straight line of the point, or the change of the angular coordinate of the normal of any point on the surface of the structure), all these changes contain the health status information of the cable system, in fact, the changes of these measurable parameters include the cable system The health state information of the support includes the generalized displacement information of the support, which means that the measurable parameters of the structure can be used to identify the generalized displacement of the support and the damaged cable. This method is based on cable force monitoring (this method refers to the monitored cable force as "monitored quantity") to identify damaged cables and support generalized displacements. In addition to being affected by the health state of the cable system and the generalized displacement of the support, the monitored quantity will also be affected by the temperature change of the cable structure (which often occurs). Under the condition that the temperature of the cable structure changes, if the monitored quantity can It is of great value to the safety of the cable structure to realize the identification of the generalized displacement of the support cable and the support with health problems. At present, there is no public and effective health monitoring system and method to solve this problem.

Contents of the invention

Technical problem: This method discloses a health monitoring method based on cable force monitoring that can reasonably and effectively identify the generalized displacement of the support and the damaged cable.

Technical solution: the method consists of three parts. They are the method of establishing the knowledge base and parameters required by the structural health monitoring system, the structural health state assessment method based on the knowledge base (including parameters) and measured monitored quantities, and the software and hardware parts of the health monitoring system.

Let the sum of the number of supporting cables of the cable structure and the number of generalized displacement components of the support of the cable structure be N. For the convenience of description, this method collectively refers to the evaluated support cables and support generalized displacements as "evaluated objects", and there are N evaluated objects. Consecutively number the evaluated objects, which will be used to generate vectors and matrices in subsequent steps.

Assuming that there are M ₁ supporting cables in the cable system, the structural cable force data includes the cable force of these M ₁ supporting cables, obviously M ₁ is smaller than the number N of the evaluated objects. It is impossible to solve the unknown states of N evaluated objects only by M ₁ cable force data of M ₁ supporting cables. This method, on the basis of monitoring all M ₁ supporting cable forces, adds no less than (NM ₁ ) other monitored quantities.

The other monitored quantities increased by not less than (NM ₁ ) are still cable forces, described as follows:

Before the structural health detection system starts to work, M ₂ (M ₂ is not less than NM ₁ ) cables are artificially added to the cable structure, which are called sensing cables. The stiffness of the newly added M ₂ sensing cables is the same as that of the cable structure. Compared with the stiffness of any supporting cable, it should be much smaller, such as 10 times smaller, and the cable force of the newly added M ₂ sensing cables should be smaller, for example, the normal stress of its cross section should be smaller than its fatigue limit, these requirements can be Ensure that the newly added M ₂ sensing cables will not suffer from fatigue damage, the two ends of the newly added M ₂ sensing cables should be fully anchored to ensure that there will be no slack, and the newly added M ₂ sensing cables should be fully anchored. The anti-corrosion protection ensures that the newly added M ₂ sensing cables will not be damaged and slack, and the cable force of the newly added M ₂ sensing cables will be monitored during the structural health monitoring process. In this method, the newly added M ₂ sensing cables are used as part of the cable structure. When referring to the cable structure later, the cable structure includes the cable structure before adding the M ₂ sensing cables and the newly added M ₂ The sense cable, that is to say, when the cable structure is mentioned later, refers to the cable structure including the newly added _M2 sensing cables. Therefore, when it is mentioned later that the "cable structure steady-state temperature data" is measured and calculated according to "the temperature measurement and calculation method of the cable structure of this method", the cable structure includes newly added _M2 sensing cables, and the obtained "cable structure The "structure steady-state temperature data" includes the steady-state temperature data of the newly added M ₂ sensing cables, and the method of obtaining the steady-state temperature data of the newly added M ₂ sensing cables is the same as that of the M ₁ supporting cables of the cable structure. The method of obtaining the steady-state temperature data will not be explained in the following text; the method of measuring the cable force of the newly added M ₂ sensing cables is the same as the method of measuring the cable force of the M ₁ supporting cables of the cable structure, It will not be explained one by one in the following text; when any measurement is carried out on the supporting cables of the cable structure, the same measurement will be carried out on the newly added M ₂ sensing cables, which will not be explained one by one in the following text; the newly added M ₂ In addition to the absence of damage and relaxation of the root sensing cables, the information content of the newly added M ₂ sensing cables is the same as that of the supporting cables of the cable structure, which will not be explained one by one in the following; the newly added M ₂ The cable force of the sensing cable is increased by not less than (NM ₁ ) other monitored quantities. When establishing various mechanical models of the cable structure later, the newly added M ₂ sensing cables are treated as the supporting cables of the cable structure. Including the newly added M ₂ sensing cables.

Based on the above-mentioned monitored quantities, the entire cable structure has M monitored quantities of M (M=M ₁ +M ₂ ) cables, and M must not be less than the number N of evaluated objects.

For convenience, in this method, "all monitored parameters of the cable structure" are referred to as "monitored quantities" for short. Number the M monitored quantities consecutively, and this number will be used to generate vectors and matrices in subsequent steps. The method uses variable j to denote this number, j=1,2,3,...,M.

The first part of the method: the method of establishing the knowledge base and parameters required by the structural health monitoring system. details as follows:

1. First determine the "temperature measurement and calculation method of the cable structure of this method". Because the temperature of the cable structure may change, for example, the temperature of different parts of the cable structure changes with the change of the sunlight intensity and the change of the ambient temperature, the surface and internal temperature of the cable structure may sometimes change with the Time-varying, the temperature of the surface and interior of the cable structure may be different, and the temperature difference between the surface and interior of the cable structure changes with time, which makes the mechanical calculation and monitoring of the cable structure quite complicated when considering temperature conditions. In order to simplify the problem, reduce the amount of calculation and reduce the cost of measurement, and to improve the calculation accuracy, this method proposes "the temperature measurement and calculation method of the cable structure of this method", which is as follows:

The first step is to query or measure the temperature-dependent heat transfer parameters of the composition materials of the cable structure and the environment where the cable structure is located, and use the design drawings, as-built drawings of the cable structure and the geometrically measured data of the cable structure to use these data and parameters The heat transfer calculation model of the cable structure is established. Query the meteorological data of not less than 2 years at the location of the cable structure in recent years, and the number of cloudy days during this period is counted as T cloudy days, and the statistics are obtained from 0:00 to the next day of each cloudy day in the T cloudy days The highest temperature and the lowest temperature between 30 minutes after sunrise time. Sunrise time refers to the meteorological sunrise time determined according to the earth's rotation and revolution laws. You can query the data or calculate the required daily temperature by conventional meteorology. At the sunrise time of a day, the maximum temperature minus the minimum temperature between 0:00 on each cloudy day and 30 minutes after the sunrise time of the next day is called the maximum temperature difference of the daily temperature of the cloudy day. There are T cloudy days, There are T maximum temperature differences of daily air temperature on cloudy days, and the maximum value among the maximum temperature differences of daily air temperature on T cloudy days is taken as the reference daily temperature difference, and the reference daily temperature difference is recorded as ΔT _r . Query the location of the cable structure and its altitude range in recent years for not less than 2 years, or obtain the temperature change data and change law of the environment where the cable structure is located with time and altitude, and calculate the location and altitude range of the cable structure The maximum change rate ΔT _h of the temperature of the environment where the cable structure is located in recent years with respect to the altitude is not less than 2 years. For the convenience of description, the unit of ΔT _h is ℃/m. Take "R cable structure surface points" on the surface of the cable structure, and then obtain the temperature of the R cable structure surface points through actual measurement, and call the measured temperature data "R cable structure surface temperature measured data", if It is to use the heat transfer calculation model of the cable structure to obtain the temperature of the surface points of the R cable structures through the heat transfer calculation, and the calculated temperature data is called "the surface temperature calculation data of the R cable structures". When taking "R cable structure surface points" on the surface of the cable structure, the conditions that must be satisfied by the quantity and distribution of "R cable structure surface points" will be described later. From the lowest altitude to the highest altitude where the cable structure is located, no less than three different altitudes are uniformly selected on the cable structure, and at each selected altitude, at the intersection of the horizontal plane and the surface of the cable structure At least two points are selected, and the outer normal of the surface of the index structure is indexed from the selected points. The direction of all selected outer normals is called "the direction of measuring the temperature distribution of the cable structure along the wall thickness", and the temperature of the cable structure along the wall thickness is measured The direction of the distribution intersects the "intersection line between the horizontal plane and the surface of the cable structure", and the selected direction for measuring the temperature distribution of the cable structure along the wall thickness must include the normal direction outside the sunny surface of the cable structure and the normal direction outside the shady surface of the cable structure along the direction of the temperature distribution along the wall thickness of each measuring cable structure, select no less than three points evenly distributed in the cable structure, especially, for the temperature distribution of the supporting cable along each measuring cable structure along the wall thickness Take only one point in the direction, that is, only measure the temperature of the surface point of the supporting cable, and measure the temperature of all selected points. The measured temperature is called "the temperature distribution data of the cable structure along the thickness", and the temperature along the same "horizontal plane and cable The "intersecting line of the surface of the structure" intersects and the "temperature distribution data of the cable structure along the thickness" measured by "the direction of measuring the temperature distribution of the cable structure along the wall thickness" is called "the temperature distribution data of the cable structure along the thickness at the same altitude" in this method. temperature distribution data", assuming that H different altitudes are selected, at each altitude, B are selected to measure the temperature distribution direction of the cable structure along the wall thickness, and the temperature along the wall thickness of each measurement cable structure is The direction of distribution selects E points in the cable structure, where H and E are not less than 3, and B is not less than 2. In particular, for the supporting cable E is equal to 1, on the cable structure "measure the temperature distribution of the cable structure along the thickness The total number of data points" is HBE, and the temperature of these HBE "points for measuring the temperature distribution data of the cable structure along the thickness" will be obtained through actual measurement later, and the temperature data obtained from the actual measurement is called "HBE cable structure along the thickness temperature measured If the heat transfer calculation model of the cable structure is used to obtain the temperature of the HBE points measuring the temperature distribution data of the cable structure along the thickness through heat transfer calculation, the calculated temperature data is called "HBE cable structure Temperature calculation data along the thickness"; in this method, at each selected altitude, the number of "temperature distribution data of the same altitude cable structure along the thickness" temperature distribution data". Meteorological temperature measurement requirements at the location of the cable structure Select a location where the temperature of the environment where the cable structure is located that meets the requirements of meteorological temperature measurement will be measured; select a location in an open and unsheltered place where the cable structure is located, and this location should be available every day of the year. The place can get the fullest sunshine of the day, and place a plate made of carbon steel at this position, called the reference plate. One side of the reference plate faces the sun, which is called the sunny side. The sunny side of the reference plate is rough and dark, the sunny side of the reference panel should be able to get the fullest sunlight that a panel can get on that day in the place every day of the year, and the non-sunny side of the reference panel is covered with thermal insulation materials, which will Real-time monitoring to obtain a reference plate temperature on the sunny side of . In this method, the time interval between any two measurements of the real-time monitoring of the same quantity shall not be greater than 30 minutes, and the time of measuring and recording data is called the time of actually recording data.

The second step is to obtain the measured data of the surface temperature of the R cable structures at the surface points of the above R cable structures through real-time monitoring, and at the same time obtain the temperature distribution data of the previously defined cable structures along the thickness through real-time monitoring. The temperature data of the environment where the cable structure is located; through real-time monitoring, the measured temperature data sequence of the environment where the cable structure is located between the sunrise time of the day and 30 minutes after the sunrise time of the next day is obtained. The measured temperature data of the environment where the cable structure is located between the sunrise time and 30 minutes after the sunrise time of the next day are arranged in chronological order. The highest temperature minus the lowest temperature in the air temperature measured data sequence of the environment where the cable structure is located is the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day, which is recorded as ΔT _emax ; the environment where the cable structure is located The measured temperature data series of the cable structure can be calculated by conventional mathematical calculations to obtain the rate of change of the temperature of the environment where the cable structure is located with respect to time, and the rate of change also changes with time; through real-time monitoring, the time between the sunrise time of the current day and 30 minutes after the sunrise time of the next day can be obtained. The measured data sequence of the temperature of the sunny side of the reference plate, the measured data sequence of the temperature of the sunny side of the reference plate is the actual measurement of the temperature of the sunny side of the reference plate between the sunrise time of the current day and 30 minutes after the sunrise time of the next day Arrange the data in chronological order, find the highest temperature and the lowest temperature in the measured data sequence of the temperature of the sunny side of the reference plate, subtract the lowest temperature from the highest temperature in the measured data sequence of the temperature of the sunny side of the reference plate to obtain the reference plate The maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day is recorded as ΔT _pmax ; through real-time monitoring, the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day is obtained. The cable structure surface temperature measured data sequences of all R cable structure surface points, there are R cable structure surface points have R cable structure surface temperature measured data sequences, each cable structure surface temperature measured data sequence consists of a cable structure surface point The measured data of the surface temperature of the cable structure between the sunrise time of the day and 30 minutes after the sunrise time of the next day are arranged in chronological order, and the highest temperature and the lowest temperature in the measured data sequence of the surface temperature of each cable structure are found, and each Subtract the minimum temperature from the highest temperature in the cable structure surface temperature measured data sequence to obtain the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day for the temperature of each cable structure surface point, there are R cable structure surfaces There are R maximum temperature difference values between the sunrise time of the day and 30 minutes after the sunrise time of the next day, and the maximum value is recorded as ΔT _smax ; from the measured data series of the surface temperature of each cable structure through conventional mathematical calculations, each The temperature change rate of a cable structure surface point with respect to time, and the temperature change rate of each cable structure surface point with respect to time also change with time. After obtaining the HBE "temperature distribution data along the thickness of the cable structure" at the same time between the sunrise time of the day and 30 minutes after the next day's sunrise time through real-time monitoring, calculate the total BE at each selected altitude. The difference between the highest temperature and the lowest temperature in the "temperature distribution data of the cable structure along the thickness at the same altitude", the absolute value of this difference is called "the maximum temperature difference in the thickness direction of the cable structure at the same altitude", H There are H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" at different altitudes, and the maximum value of the H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" is "the maximum temperature difference in the thickness direction of the cable structure" , recorded as ΔT _tmax .

The third step is to measure and calculate the steady-state temperature data of the cable structure; first, determine the time to obtain the steady-state temperature data of the cable structure. There are six conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure. The first condition is The time to obtain the steady-state temperature data of the cable structure is between the sunset time of the day and 30 minutes after the sunrise time of the next day. The sunset time refers to the meteorological sunset time determined according to the laws of the earth's rotation and revolution. You can query the data or pass The required sunset time of each day is calculated by conventional meteorology; the second condition a condition is that during the period between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, the maximum temperature difference ΔT of the reference plate Neither _pmax nor the maximum temperature difference ΔT _smax on the surface of the cable structure is greater than 5 degrees Celsius; the b condition of the second condition is obtained from the previous measurement and calculation during the period between the sunrise of the day and 30 minutes after the sunrise of the next day The maximum environmental error ΔT _emax is not greater than the reference daily temperature difference ΔT _r , and the maximum temperature difference ΔT _pmax of the reference plate minus 2 degrees Celsius is not greater than ΔT _emax , and the maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than ΔT _pmax ; only the second item is required One of the a condition and b condition is said to meet the second condition; the third condition is that at the moment when the cable structure steady-state temperature data is obtained, the absolute value of the temperature change rate of the cable structure environment with respect to time is not equal to greater than 0.1 degrees Celsius per hour; the fourth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of each cable structure surface point in the R cable structure surface points with respect to time is not greater than one hour 0.1 degrees Celsius; the fifth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the measured data of the surface temperature of the cable structure at each of the R cable structure surface points is from the sunrise of the day to the sunrise of the next day The minimum value between 30 minutes after the time; the sixth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the "maximum temperature difference in the thickness direction of the cable structure" ΔT _tmax is not greater than 1 degree Celsius; this method utilizes the above six conditions, Any one of the following three moments is called "the mathematical moment for obtaining the steady-state temperature data of the cable structure". The moment of the first to fifth conditions, the second moment is the moment that only satisfies the sixth condition in the above "conditions related to the moment of determining the steady-state temperature data of the cable structure", and the third moment is at the same time The moment when the first to sixth conditions in the above "conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure" are met; the mathematical moment when the steady-state temperature data of the cable structure is obtained is the time when the data is actually recorded in this method When one of the time, the moment of obtaining the steady-state temperature data of the cable structure is the mathematical moment of obtaining the steady-state temperature data of the cable structure; if the mathematical moment of obtaining the steady-state temperature data of the cable structure is not any moment in the actual recording data moment , then take the mathematical moment closest to obtaining the steady-state temperature data of the cable structure by this method The moment of actually recording the data is the moment of obtaining the steady-state temperature data of the cable structure; this method will use the measured and recorded quantity at the moment of obtaining the steady-state temperature data of the cable structure to carry out the related health monitoring analysis of the cable structure; this method approximately considers that the obtained cable structure The temperature field of the cable structure at the moment of the steady-state temperature data of the structure is in a steady state, that is, the temperature of the cable structure at this moment does not change with time, and this moment is the "moment of obtaining the steady-state temperature data of the cable structure" of this method; Heat transfer characteristics, using the “measured surface temperature data of R cable structures” and “measured temperature data of HBE cable structures along the thickness” at the moment when the steady-state temperature data of the cable structure is obtained, using the heat transfer calculation model of the cable structure, through conventional The heat transfer calculation obtains the temperature distribution of the cable structure at the moment when the steady-state temperature data of the cable structure is obtained. At this time, the temperature field of the cable structure is calculated according to the steady state, and the calculated cable structure The temperature distribution data includes the calculated temperature of R cable structure surface points on the cable structure, and the calculated temperature of R cable structure surface points is called the R cable structure steady-state surface temperature calculation data, and also includes the HBE selected in front of the cable structure The calculation temperature of the "points for measuring the temperature distribution data of the cable structure along the thickness", the calculation temperature of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness" is called "the HBE temperature calculation data of the cable structure along the thickness", When the measured surface temperature data of the R cable structures is equal to the calculated data of the steady-state surface temperature of the R cable structures, and the "measured data of the temperature along the thickness of the HBE cable structures" is correspondingly equal to the "calculated data of the temperature along the thickness of the HBE cable structures" , the calculated temperature distribution data of the cable structure at the moment when the cable structure steady-state temperature data is obtained is called "cable structure steady-state temperature data" in this method, and the "R cable structure surface temperature measured data" at this time It is called "the measured data of steady-state surface temperature of R cable structures", and "the measured data of temperature of HBE cable structures along the thickness" is called "the measured data of steady-state temperature of HBE cable structures along the thickness"; When there are R cable structure surface points", the quantity and distribution of "R cable structure surface points" must meet three conditions. The first condition is that when the cable structure temperature field is in a steady state, when any point on the cable structure surface When the temperature is obtained through the linear interpolation of the measured temperature of the point adjacent to the arbitrary point on the surface of the cable structure among the "R cable structure surface points", the temperature of the arbitrary point on the surface of the cable structure obtained by linear interpolation is the same as that on the surface of the cable structure The error of the actual temperature at this arbitrary point is not greater than 5%; the surface of the cable structure includes the surface of the supporting cable; the second condition is that the number of points at the same altitude in the "R cable structure surface points" is not less than 4, and "R The points at the same altitude in "R cable structure surface points" are evenly distributed along the cable structure surface; the absolute value of the difference in altitude between all pairwise adjacent cable structure surface points along the altitude of "R cable structure surface points" The maximum value Δh in is not greater than the value obtained by dividing ΔT _h by 0.2°C. For the convenience of description, the unit of ΔT _h is ℃/m, and the unit of Δh is m for convenience of description; "R The definition of two adjacent cable structure surface points along the altitude refers to that when only the altitude is considered, there is no cable structure surface point in the "R cable structure surface points", and the cable structure surface The altitude value of the point is between the altitude values of two adjacent cable structure surface points; the third condition is to query or calculate according to meteorological routines to obtain the sunshine law of the cable structure location and the altitude interval, and then according to the cable structure The geometric characteristics and azimuth data of the cable structure are used to find the positions of the surface points on the cable structure that receive the most sunshine time throughout the year. At least one cable structure surface point in the "R cable structure surface points" is on the cable structure that receives the sunshine throughout the year. One of those surface points where time is most abundant.

2. The method of establishing the initial mechanical calculation benchmark model A _o (such as the finite element benchmark model) and the current initial mechanical calculation benchmark model A ^t _o (such as the finite element benchmark model) of the cable structure, and establishing the initial monitored quantity corresponding to A _o The method of numerical vector C _o , the method of establishing the current initial numerical vector C _o of the monitored quantity corresponding to A ^t _o . In this method, A _o , C _o , A ^t _o and C ^t _o are constantly updated. The method of establishing and updating A _o , C _o , A ^t _o and C _o is as follows. The numbering rule of the initial value vector C _o of the monitored quantity is the same as that of the M monitored quantities.

When the initial mechanical calculation benchmark model A _o is established, when the cable structure is completed, or before the establishment of the structural health monitoring system, the "cable structure steady-state temperature data" is measured and calculated according to the "temperature measurement and calculation method of the cable structure" (It can be measured by conventional temperature measurement methods, such as thermal resistance measurement). At this time, the "cable structure steady-state temperature data" is represented by a vector T _o , which is called the initial cable structure steady-state temperature data vector T _o . At the same time when T _o is measured, that is, at the same moment when the steady-state temperature data of the cable structure is obtained, the initial numbers of all monitored quantities of the cable structure are directly measured and calculated using conventional methods. The physical parameters (such as thermal expansion coefficient) and mechanical performance parameters (such as elastic modulus, Poisson's ratio) of various materials used in the cable structure that change with temperature are obtained by conventional methods (research data or actual measurement); At the same time as the steady-state temperature data vector T _o of the cable structure, that is, at the same moment when the steady-state temperature data of the cable structure is obtained, the actual measurement and calculation data of the cable structure are obtained by using conventional methods for actual measurement and calculation. The measured and calculated data of the cable structure includes the non-destructive testing data of the supporting cable and other data that can express the health state of the cable, the initial geometric data of the cable structure, the data of the cable force, the tension data of the tie rod, the generalized coordinate data of the initial cable structure support, the cable structure support Measured data such as initial generalized displacement measurement data, cable structure modal data, structural strain data, structural angle measurement data, and structural space coordinate measurement data. The initial geometric data of the cable structure can be the spatial coordinate data of all cable end points plus the spatial coordinate data of a series of points on the structure, the purpose is to determine the geometric characteristics of the cable structure according to these coordinate data. The initial generalized displacement measurement data of the cable structure support refers to the generalized displacement of the cable structure support relative to the support in the design state of the cable structure when the initial mechanical calculation benchmark model A _o is established. For cable-stayed bridges, the initial geometric data can be the spatial coordinate data of all cable end points plus the spatial coordinate data of several points on both ends of the bridge, which is the so-called bridge type data. Using the non-destructive testing data of supporting cables and other data that can express the health status of supporting cables and the initial generalized displacement measurement data of cable structure supports to establish the initial damage vector d _o of the evaluated object (as shown in formula (1)), expressed by d _o The initial health state of the evaluated object of the cable structure (expressed by the initial mechanical calculation benchmark model A _o ). If there is no non-destructive testing data of the supporting cable and other data that can express the health state of the supporting cable, or when the initial state of the structure can be considered as a state of no damage and no relaxation, the value of each element related to the supporting cable in the vector d _o is set to 0 , if there is no measurement data of the initial generalized displacement of the cable structure support or it can be considered that the initial generalized displacement of the cable structure support is 0, the value of each element in the vector d _o related to the generalized displacement of the cable structure support is 0. Utilize the design drawing, as-built drawing of the cable structure and the measured data of the initial cable structure, the non-destructive testing data of the supporting cable, the initial generalized displacement measurement data of the support of the cable structure, the physics and mechanics of various materials used in the cable structure changing with temperature The performance parameters and the initial cable structure steady-state temperature data vector T _o are included in the "cable structure steady-state temperature data" by mechanical methods (such as finite element method) to establish the initial mechanical calculation benchmark model A _o .

d _o =[d _o1 d _o2 ··· d _ok ··· d _oN ] ^T (1)

In formula (1), d _ok (k=1,2,3,...,N) represents the initial state of the kth evaluated object in the initial mechanical calculation benchmark model A _o , if the evaluated The object is a cable (or tie rod) in the cable system, then d _ok represents its initial damage, when d _ok is 0, it means no damage, and when it is 100%, it means that the cable completely loses its bearing capacity, between 0 and 100% Time represents the loss of the bearing capacity of the corresponding proportion. If the evaluated object is a generalized displacement component of a support, then d _ok represents its initial displacement value, and T represents the transposition of the vector (the same below).

At the same time when T _o is measured, that is, at the same moment when the steady-state temperature data of the cable structure is obtained, the initial values of all the monitored quantities of the calculated cable structure are directly measured by conventional methods to form the initial value vector of the monitored quantities C _o (see formula (2)). It is required to obtain C _o while obtaining A _o , and the initial value vector C _o of the monitored quantity represents the specific value of the "monitored quantity" corresponding to A _o . Because under the aforementioned conditions, the monitored quantity calculated based on the calculation reference model of the cable structure is reliably close to the measured data of the initial monitored quantity, in the following description, the calculated value and the measured value will be represented by the same symbol.

C _o =[C _o1 C _o2 ··· C _oj ··· C _oM ] ^T (2)

In formula (2), C _oj (j=1,2,3,...,M) is the initial quantity of the jth monitored quantity in the cable structure, and this component corresponds to a specific j monitored quantities.

No matter what method is used to obtain the initial mechanical calculation benchmark model A _o , the cable structure calculation data calculated based on A _{o must} be very Close to the measured data, the error is generally not greater than 5%. In this way, the calculation data of cable force, strain, shape and displacement of cable structure, angle data of cable structure, spatial coordinate data of cable structure, etc. under the simulated situation obtained by A _o calculation can be reliably close to the simulated situation The measured data when it actually happened. The health state of the evaluated object in the model A _o is represented by the initial damage vector d _o of the evaluated object, and the steady-state temperature data of the cable structure is represented by the initial steady-state temperature data vector T _o of the cable structure. Since the calculated values of all monitored quantities calculated based on A _o are very close to the initial values of all monitored quantities (obtained by actual measurement), it can also be used on the basis of A _o to perform mechanical calculations, and each monitored quantity of A _o The calculated numerical value of the monitored quantity constitutes the initial numerical vector C _o of the monitored quantity. T _o and d _o are the parameters of A _o , and it can also be said that C _o is composed of the mechanical calculation results of A _o .

The method of establishing and updating the current initial mechanical calculation benchmark model A ^t _o is: at the initial moment (that is, when A ^t _o is established for the first time), A ^t _o is equal to A _o , and the corresponding "cable structure steady state" of A ^t _o Temperature data" is recorded as "current initial cable structure steady-state temperature data vector T ^t _o ", at the initial moment, T ^t _o is equal to T _o , and the definition of vector T ^t _o is the same as that of vector T _o . The initial health state of the evaluated object of A ^t _o is the same as the health state of the evaluated object of A _o , which is also represented by the initial damage vector d _o of the evaluated object. In the following cycle, the initial health state of the evaluated object of A ^t _o The health state is always expressed by the initial damage vector d _o of the evaluated object; when the cable structure is in the state A ^t _o , this method uses the current initial value vector C _o of the monitored quantity to represent the specific values of all the monitored quantities, and the elements of C _o are the same as C The elements of _o are in one _- to _- one correspondence, respectively representing the specific values of all the monitored quantities when the cable structure is in the two states of A to and A ^o . At the initial moment, C _o is equal to C _o , T ^t _o and d _o are the parameters of A ^t _o , and C ^t _o is composed of the mechanical calculation results of A ^t _o ; The current data of "cable structure steady-state temperature data" is continuously measured and calculated (called "current cable structure steady-state temperature data vector T ^t ", the definition of vector T ^t is the same as the definition of vector T _o in the same way); if T ^t is equal to T ^t _o , A ^t _o does not need to be updated, otherwise A ^t _o and T ^t _o need to be updated. The update method is: the first step is to calculate the difference between T ^t and T _o , the difference between T ^t and T _o is the change of the current cable structure steady-state temperature data with respect to the initial cable structure steady-state temperature data, and the difference between T ^t and T _o is represented by the steady-state temperature change vector S, which is equal to T ^t minus T _o , S represents the change of the steady-state temperature data of the cable structure; in the second step, the temperature change is applied to the cable structure in A _o , and the value of the applied temperature change is taken from the steady-state temperature change vector S, for the cable structure in A _o After the temperature change is applied, the updated current initial mechanical calculation benchmark model A ^t _o is obtained. When A ^t _o is updated, all element values of T ^t _o are also replaced by corresponding values of all elements of T ^t , that is, T ^t _o is updated. The T ^t _o corresponding to A ^t _o is obtained correctly; the method of updating C ^t _o is: after updating A ^t _o , the current specific values of all monitored quantities in A ^t _o are obtained through mechanical calculations, these Concrete numerical composition C ^t _o .

The current value of all the monitored quantities in the cable structure constitutes the current value vector C of the monitored quantity (see formula (3) for the definition).

C=[C ₁ C ₂ ··· C _j ··· C _M ] ^T (3)

In formula (3), C _j (j=1,2,3,...,M) is the current value of the jth monitored quantity in the cable structure, and this component C _j is related to C _oj according to the numbering rule Corresponding to the same "monitored quantity". At the same moment when the current steady-state temperature data vector T ^t of the cable structure is measured, the current measured values of all the monitored quantities of the cable structure are obtained through actual measurement to form the current value vector C of the monitored quantities.

3. A method for establishing and updating the change matrix ΔC of the unit damage of the cable structure unit to be monitored.

The unit change matrix ΔC of the cable structure unit damage monitored quantity is constantly updated, that is, while updating the current initial mechanical calculation benchmark model A ^t _o and the current initial value vector C ^t _o of the monitored quantity, the cable structure unit damage monitored quantity is updated at the same time Unit change matrix ΔC. The specific method is as follows:

Several calculations are performed on the basis of the current initial _mechanical calculation ^benchmark model A to of the cable structure, and the number of calculations is numerically equal to the number of all evaluated objects. Each calculation assumes that there is only one evaluated object to add unit damage or unit generalized displacement on the basis of the initial damage (expressed by the corresponding element of vector d _o ), specifically, if the evaluated object is a support in the cable system cable, then it is assumed that the supporting cable has unit damage (for example, take 5%, 10%, 20% or 30% damage as unit damage), if the evaluated object is a generalized displacement component of a support in one direction, then Assume that the support has a unit generalized displacement in the displacement direction (for example, take 1 mm, 2 mm, 3 mm, etc. etc. is the unit angular displacement), and use D _uk to record this unit damage or unit generalized displacement, where k represents the number of the evaluated object that has suffered unit damage or unit generalized displacement. Use "unit damage or unit generalized displacement vector D _u " (as shown in equation (4)) to record all unit damage or unit generalized displacement. The evaluated object with unit damage or unit generalized displacement in each calculation is different from the evaluated object with unit damage or unit generalized displacement in other calculations. Each calculation uses mechanical methods (such as finite element method) to calculate the cable structure. The current calculated values of all the monitored quantities, and the current calculated values of all the monitored quantities obtained by each calculation form a current vector of the monitored quantities (when it is assumed that the kth evaluated object has unit damage or unit generalized displacement, the available formula (5) Indicates that the monitored quantity calculates the current vector Each calculation gets the monitored quantity and calculates the current vector Subtract the current initial value vector C ^t _o of the monitored quantity and then divide it by the unit damage or unit generalized displacement value C _uk assumed in this calculation, the obtained vector is The number of the object is marked) the unit change vector of the monitored quantity (when the kth assessed object has unit damage or unit generalized displacement, use δC _k to represent the unit change vector of the monitored quantity, see formula (6) for the definition), is Each element of the monitoring quantity unit change vector represents the unit change of the monitored quantity corresponding to the element caused by the unit damage or unit generalized displacement of the assessed object assumed to have unit damage or unit generalized displacement during calculation; There are N monitored quantity unit change vectors for N evaluated objects. Since there are M monitored quantities, each monitored quantity unit change vector has M elements, which are composed of the N monitored quantity unit change vectors in sequence There is a monitored quantity unit change matrix ΔC with M×N elements, and the definition of ΔC is shown in formula (6).

D _u =[D _u1 D _u2 ··· D _uk ··· D _uN ] ^T (4)

The element D _uk (k=1,2,3,...,N) of the unit damage or unit generalized displacement vector D _u in formula (4) represents the unit damage or unit generalized displacement of the kth evaluated object displacement value.

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{\left[\begin{array}{cccccccccc}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}& {\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; tj</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; tM</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}\end{array}\right]}^{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

Elements in formula (5) (k=1,2,3,....,N; j=1,2,3,....,M) means that due to the kth evaluated object has unit damage or unit In the case of generalized displacement, the current calculated quantity of the jth monitored quantity corresponding to the numbering rule.

$\mathrm{<span\; class="notranslate">\; \&delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}}{{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; uk</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

$\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; =</span>\left[\begin{array}{cccccc}\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1,1</span>}}& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1,2</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; N</span>}}\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 2,1</span>}}& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 2,2</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; N</span>}}\\ <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 1</span>}}& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 2</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; N</span>}}\\ <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 1</span>}}& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 2</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; k</span>}}& <span\; class="notranslate">\; .</span>& \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; N</span>}}\end{array}\right]<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

In formula (7), ΔC _{j, k} (k=1,2,3,...,N; j=1,2,3,...,M) means only due to the The unit change (algebraic value) of the current value of the jth monitored quantity corresponding to the numbering rule caused by the unit damage or unit generalized displacement of the k root of the assessed object (algebraic value), the unit change vector of the monitored quantity δC _k is actually is a column in the matrix ΔC.

4. The current numerical vector C of the monitored quantity (calculated or measured) is the same as the current initial numerical vector C ^t _o of the monitored quantity, the unit change matrix ΔC of the monitored quantity per unit damage, the unit damage or unit generalized displacement vector C _u and the current value of the evaluated object The approximate linear relationship between the nominal damage vector d is shown in formula (8) or formula (9). For the definition of the current nominal damage vector d of the evaluated object, refer to formula (10).

$\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 8</span>}<span\; class="notranslate">\; )</span>$

$\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 9</span>}<span\; class="notranslate">\; )</span>$

d=[d ₁ d ₂ ··· d _k ··· d _N ] ^T (10)

In formula (10), d _k (k=1,2,3,...,N) is the current health status of the kth evaluated object in the cable structure, if the evaluated object is in the cable system A cable (or tie rod), then d _k represents its current damage. When d _k is 0, it means no damage. When it is 100%, it means that the cable completely loses its bearing capacity. When it is between 0 and 100%, it means that it loses its corresponding Proportional bearing capacity, if the evaluated object is a generalized displacement component of a support, then d _k represents its current displacement value.

The linear relationship error vector e defined by formula (11) can express the error of the linear relationship shown in formula (8) or formula (9).

$\mathrm{<span\; class="notranslate">\; e</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; abs</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 11</span>}<span\; class="notranslate">\; )</span>$

In formula (11), abs() is an absolute value function, and the absolute value is taken for each element of the vector obtained in the brackets.

The second part of this method: a structural health assessment method based on the knowledge base (including parameters) and measured monitored quantities.

Since there is a certain error in the linear relationship represented by formula (8) or formula (9), it is not possible to directly solve the current nominal Damage vector d. If this is done, the elements in the current nominal damage vector d of the evaluated object may even have relatively large negative values, that is, negative damage, which is obviously unreasonable. Therefore, it is a reasonable solution to obtain an acceptable solution of the current nominal damage vector d of the evaluated object (that is, with a reasonable error, but the position of the damaged cable and its damage degree can be determined more accurately from the cable system), which can be used Formula (12) to express this method.

$\mathrm{<span\; class="notranslate">\; abs</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; g</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 12</span>}<span\; class="notranslate">\; )</span>$

In Equation (12), abs() is an absolute value function, and the vector g describes the reasonable deviation from the ideal linear relationship (Equation (8) or Equation (9)), which is defined by Equation (13).

g=[g ₁ g ₂ ··· g _j ··· g _M ] ^T (13)

g _j (j=1,2,3,...,M) in formula (13) describes the maximum allowable deviation from the ideal linear relationship shown in formula (8) or formula (9). The vector g can be selected according to the error vector e defined by formula (11).

When the current initial numerical vector C ^t _o of the monitored quantity, the unit change matrix ΔC of the monitored quantity with unit damage, and the current numerical vector C of the measured measured quantity are known, an appropriate algorithm (such as a multi-objective optimization algorithm) can be used to solve the formula (12 ), to obtain an acceptable solution to the current nominal damage vector d of the evaluated object.

Define the current actual damage vector d ^a of the evaluated object (see formula (14)), and the health status of the evaluated object can be determined by d ^a .

${\mathrm{<span\; class="notranslate">\; d</span>}}^{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; =</span>{\left[\begin{array}{cccccccccc}{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; a</span>}}& {\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; a</span>}}& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}^{\mathrm{<span\; class="notranslate">\; a</span>}}& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& <span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}^{\mathrm{<span\; class="notranslate">\; a</span>}}\end{array}\right]}^{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 14</span>}<span\; class="notranslate">\; )</span>$

In formula (14), d ^a _k (k=1,2,3,...,N) represents the current actual health status of the kth evaluated object, if the evaluated object is the A cable (or tie rod), then d ^a _k represents its current actual damage, and its definition is shown in formula (15). When d ^a _k is 0, it means no damage, and when it is 100%, it means that the cable completely loses its bearing capacity, between When between 0 and 100%, it means that the bearing capacity of the corresponding proportion is lost; if the evaluated object is a generalized displacement component of a support, its definition is shown in formula (15), then d ^a _k represents its current actual generalized displacement value, The numbering rules of the elements of the vector d ^a are the same as the numbering rules of the elements of the vector d _o in formula (1).

In formula (15), d _ok (k=1,2,3,...,N) is the kth element of vector d _o , and d _k is the kth element of vector d.

The third part of the method: the software and hardware part of the health monitoring system.

The hardware part includes monitoring system (including monitored quantity monitoring system and temperature monitoring system), signal collector and computer, etc. Real-time monitoring is required to obtain the measured data of the required temperature, and it is required to monitor each monitored quantity in real time at the same time.

The software should be able to complete the monitoring, recording, control, storage, calculation, notification, alarm and other functions required by this method and can be realized by computer.

This method specifically includes:

a. For the convenience of description, this method collectively refers to the evaluated support cables and support generalized displacement components as the evaluated object. Let the sum of the number of evaluated support cables and support generalized displacement components be N, that is, the The number of evaluation objects is N; determine the numbering rule of the evaluation object, according to this rule, all the evaluation objects in the index structure will be numbered, and the number will be used to generate vectors and matrices in subsequent steps; this method uses variable k to represent this One number, k=1,2,3,...,N; suppose there are M ₁ supporting cables in the cable system, the cable force data of the cable structure includes the cable force of these M ₁ supporting cables, obviously M ₁ is less than the estimated The number of objects is N; it is impossible to solve the unknown state of N evaluated objects only through M ₁ cable force data of M ₁ supporting cables. This method is based on monitoring all M ₁ supporting cable forces. M ₂ cables are artificially added to the cable structure, called sensing cables, and the cable force of the newly added M ₂ sensing cables will be monitored during the health monitoring process of the cable structure; M cable forces of M cables are monitored, that is, there are M monitored quantities, where M is the sum of M ₁ and M ₂ ; M should be greater than the number N of objects to be evaluated; the newly added M ₂ sensing cables Compared with the stiffness of any supporting cable of the cable structure, the stiffness should be much smaller; the cable force of each sensing cable of the newly added M ₂ sensing cables should be smaller than that of any supporting cable of the cable structure This can ensure that even if the newly added M ₂ sensing cables are damaged or slack, the influence on the stress, strain and deformation of other components of the cable structure is minimal; the cross-section of the newly added M ₂ sensing cables The upper normal stress should be less than its fatigue limit. These requirements can ensure that the newly added M ₂ sensing cables will not suffer from fatigue damage; the two ends of the newly added M ₂ sensing cables should be fully anchored to ensure that there will be no slack; The newly added M ₂ sensing cables should be fully protected against corrosion to ensure that the newly added M ₂ sensing cables will not be damaged or loosened; for convenience, in this method, the "monitored cable structure All parameters" are referred to as "monitored quantities" for short; M monitored quantities are serially numbered, and the method uses variable j to represent this number, j=1,2,3,...,M, and this number will be used in subsequent steps Used to generate vectors and matrices; in this method, the newly added M ₂ sensing cables are used as part of the cable structure. When the cable structure is mentioned later, the cable structure includes the cable structure before adding M ₂ sensing cables and Newly increased M ₂ sensing cables, that is to say, refer to the cable structure including the newly added M ₂ sensing cables when referring to the cable structure in the following text; When the "cable structure steady-state temperature data" is measured and calculated by "calculation method", the cable structure includes newly added M ₂ sensing cables, and the obtained "cable structure steady-state temperature data" includes newly added M ₂ sensor cables The steady-state temperature data of the cable, the method of obtaining the steady-state temperature data of the newly added M ₂ sensing cables is the same as the steady-state temperature data of the M ₁ supporting cables of the cable structure The method will not be explained one by one in the following text; the method of measuring the cable force of the newly added M ₂ sensing cables is the same as the measuring method of the cable force of the M ₁ supporting cables in the cable structure, and will not be repeated in the following text. One explanation; when carrying out any measurement on the supporting cables of the cable structure, the same measurement is carried out on the newly added M ₂ sensing cables, which will not be explained one by one in the following; the newly added M ₂ sensing cables except the In addition to damage and relaxation, the information requirements and acquisition methods for the newly added M ₂ sensing cables are the same as the information requirements and acquisition methods for the supporting cables of the cable structure, and will not be explained one by one in the following; When establishing various mechanical models of the cable structure, the newly added _M2 sensing cables are treated as the supporting cables of the cable structure; When supporting cable, said supporting cable comprises the supporting cable of cable structure and newly increased M ₂ sensing cables; In this method, the time interval between any two measurements of the real-time monitoring of the same amount must not be greater than 30 minutes, The moment of measuring and recording data is called the moment of actually recording data;

b. This method defines "the temperature measurement and calculation method of the cable structure of this method" according to steps b1 to b3;

b1: Query or measure the temperature-dependent heat transfer parameters of the composition materials of the cable structure and the environment where the cable structure is located, use the design drawings, as-built drawings of the cable structure, and the geometrically measured data of the cable structure, and use these data and parameters to establish a cable structure. The heat transfer calculation model of the structure; query the meteorological data of not less than 2 years in recent years where the cable structure is located, and count the number of cloudy days during this period as T cloudy days. In this method, the number of cloudy days that cannot be seen during the day The whole day of the sun is called a cloudy day, and the highest and lowest temperature between 0:00 and 30 minutes after the sunrise time of the next day on each of the T cloudy days is counted. The meteorological sunrise time determined by the sun and the revolution law does not mean that the sun can be seen on that day. You can check the data or calculate the required daily sunrise time through conventional meteorological calculations. Every cloudy day from 0:00 to 19:00 The maximum temperature difference between the highest temperature and the lowest temperature within 30 minutes after sunrise of the next day is called the maximum temperature difference of the daily temperature of the cloudy day. If there are T cloudy days, there will be the maximum temperature difference of the daily temperature of T cloudy days. Take T The maximum value of the maximum temperature difference of daily air temperature in a cloudy day is the reference daily temperature difference, which is recorded as ΔT _r ; query the location of the cable structure and the altitude interval of not less than 2 years of meteorological data in recent years or obtain the cable structure from actual measurements The change data and change law of the temperature of the environment with time and altitude, and the maximum change rate ΔT of the temperature of the environment where the cable structure is located with respect to the altitude in recent years for the location of the cable structure and the altitude interval of not less than 2 years in recent years _h , for the convenience of description, the unit of ΔT _h is ℃/m; take "R cable structure surface points" on the surface of the cable structure, and the specific principle of taking "R cable structure surface points" is described in step b3, and later The temperature of the surface points of the R cable structures will be obtained through actual measurement, and the temperature data obtained from the actual measurement is called "the measured data of the surface temperature of the R cable structures". The temperature of the surface points of the R cable structures is called the calculated temperature data as "calculation data of the surface temperature of the R cable structures"; For less than three different altitudes, at each selected altitude, at least two points are selected at the intersection of the horizontal plane and the surface of the cable structure, and the outer normal of the surface of the structure is indexed from the selected point, all selected The outer normal direction is called "the direction of measuring the temperature distribution of the cable structure along the wall thickness". The direction of temperature distribution along the wall thickness must include the outer normal direction of the sunny surface of the cable structure and the outer normal direction of the shaded surface of the cable structure, and the temperature distribution along the wall thickness of each measurement cable structure is uniform in the cable structure. Select no less than three points, in particular, only one point is taken for the supporting cable along the direction of temperature distribution of each measuring cable structure along the wall thickness, that is, only the temperature of the surface point of the supporting cable is measured, and all selected points are measured The measured temperature is called "the temperature distribution of the cable structure along the thickness distribution data", in which the "temperature distribution data of the cable structure along the thickness" measured along the "intersection line between the horizontal plane and the surface of the cable structure" and "the direction of measuring the temperature distribution of the cable structure along the wall thickness" are obtained in this paper The method is called "the temperature distribution data of the cable structure along the thickness at the same altitude", assuming that H different altitudes are selected, and at each altitude, B are selected to measure the temperature distribution direction of the cable structure along the wall thickness , select E points in the cable structure along the direction of measuring the temperature distribution along the wall thickness of each cable structure, where H and E are not less than 3, and B is not less than 2. In particular, for the supporting cable E is equal to 1, the calculation The total number of "points for measuring the temperature distribution data of the cable structure along the thickness" on the cable structure is HBE, and the temperature of these HBE "points for measuring the temperature distribution data of the cable structure along the thickness" will be obtained through actual measurement later, which is called the actual measurement. The temperature data is the "measured temperature data along the thickness of the HBE cable structure". If the heat transfer calculation model of the cable structure is used to obtain the temperature of the point of the HBE measuring the temperature distribution data of the cable structure along the thickness through heat transfer calculation, it is The calculated temperature data is called "HBE cable structure temperature calculation data along the thickness"; in this method, the temperature distribution data of the "temperature distribution data of the same altitude cable structure along the thickness" at each selected altitude "; select a location at the location of the cable structure according to the requirements of meteorological temperature measurement, and the temperature of the environment where the cable structure is located that meets the requirements of meteorological measurement of temperature will be measured at this location; The position should be able to get the fullest sunshine of the day that the place can get every day of the year. A carbon steel plate is placed at this position, called the reference plate. The reference plate cannot be in contact with the ground. The distance between the slab and the ground is not less than 1.5 meters. One side of the reference slab faces the sun, which is called the sunny side. The sunny side of the reference slab is rough and dark. The sunny side of the reference slab should be available every day of the year. The most sufficient sunshine of the day that a panel can get at this place, the non-sun-facing side of the reference panel is covered with thermal insulation material, and the temperature of the sunny side of the reference panel will be obtained through real-time monitoring;

b2: Obtain the measured surface temperature data of the R cable structures at the surface points of the above R cable structures through real-time monitoring, and at the same time obtain the temperature distribution data of the previously defined cable structures along the thickness through real-time monitoring. The temperature data of the environment where the structure is located; through real-time monitoring, the temperature measured data series of the environment where the cable structure is located is obtained from the sunrise time of the day to 30 minutes after the sunrise time of the next day. The measured temperature data of the environment where the cable structure is located between the time and 30 minutes after sunrise of the next day are arranged in chronological order, and the highest temperature and the lowest temperature in the air temperature measurement data sequence of the environment where the cable structure is located are found. The maximum temperature difference in the air temperature measured data sequence minus the minimum temperature is the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day in the environment where the cable structure is located, which is called the maximum temperature difference of the environment, and is recorded as ΔT _emax ; The temperature measured data sequence of the environment where the cable structure is located is obtained through conventional mathematical calculations. The measured data series of the temperature of the sunny side of the reference plate between 30 minutes, the measured data series of the temperature of the sunny side of the reference plate from the sunrise time of the current day to the sunny side of the reference plate 30 minutes after the sunrise time of the next day The measured data of the temperature of the reference plate are arranged in chronological order, find the highest temperature and the lowest temperature in the measured data sequence of the temperature of the sunny side of the reference plate, and subtract the lowest temperature from the highest temperature in the measured data sequence of the temperature of the sunny side of the reference plate Temperature obtains the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day from the temperature of the sunny side of the reference plate, which is called the maximum temperature difference of the reference plate, and is recorded as ΔT _pmax ; The measured data series of cable structure surface temperature of all R cable structure surface points between 30 minutes after the sunrise time of the next day, there are R cable structure surface temperature measured data sequences of R cable structure surface points, each cable structure The measured data sequence of the surface temperature is arranged in chronological order by the measured data of the surface temperature of the cable structure between the sunrise time of the day and 30 minutes after the sunrise time of the next day at a surface point of the cable structure, and the measured data sequence of the surface temperature of each cable structure is found From the highest temperature and the lowest temperature in the data series, subtract the lowest temperature from the highest temperature in the measured data series of the surface temperature of each cable structure to obtain the temperature of each cable structure surface point from the sunrise time of the day to 30 minutes after the sunrise time of the next day If there are R surface points of the cable structure, there are R maximum temperature difference values between the sunrise time of the day and 30 minutes after the sunrise time of the next day, and the maximum value is called the maximum temperature difference of the cable structure surface, which is denoted as ΔT _smax ; From the measured data sequence of the surface temperature of each cable structure, the rate of change of the temperature of each cable structure surface point with respect to time is obtained through conventional mathematical calculations, and the temperature of each cable structure surface point with respect to time The rate of change also changes with time; after obtaining HBE "temperature distribution data along the thickness of the cable structure" at the same time between the sunrise time of the day and 30 minutes after the sunrise time of the next day through real-time monitoring, calculate the The difference between the maximum temperature and the minimum temperature in a total of BE "temperature distribution data of the cable structure along the thickness at the same altitude" at a selected altitude, the absolute value of this difference is called "thickness direction of the cable structure at the same altitude". If H different altitudes are selected, there will be H "maximum temperature differences in the thickness direction of the cable structure at the same altitude", and the maximum value of the H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" is "The maximum temperature difference in the thickness direction of the cable structure", denoted as ΔT _tmax ;

b3: Measurement and calculation to obtain the steady-state temperature data of the cable structure; firstly, determine the moment to obtain the steady-state temperature data of the cable The time of the structural steady-state temperature data is between the sunset time of the current day and 30 minutes after the sunrise time of the next day. The sunset time refers to the meteorological sunset time determined according to the laws of the earth's rotation and revolution. You can query the data or through the conventional weather The required sunset time of each day can be obtained through scientific calculation; the second condition a condition is that during the period between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, the maximum temperature difference ΔT _pmax and the maximum temperature difference of the reference plate The maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than 5 degrees Celsius; the b condition of the second condition is that during the period between the sunrise of the day and 30 minutes after the sunrise of the next day, in the environment obtained by the previous measurement and calculation The maximum error ΔT _emax is not greater than the reference daily temperature difference ΔT _r , and the maximum temperature difference ΔT _pmax of the reference plate minus 2 degrees Celsius is not greater than ΔT _emax , and the maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than ΔT _pmax ; it only needs to satisfy the second item a One of the condition and b condition is said to meet the second condition; the third condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of the environment where the cable structure is located with respect to time is not greater than each 0.1 degrees Celsius per hour; the fourth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of each cable structure surface point in the R cable structure surface points with respect to time is not greater than 0.1 degrees Celsius per hour The fifth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the measured data of the cable structure surface temperature of each cable structure surface point in the R cable structure surface points is from the sunrise time of the day to the day after the sunrise time of the next day The minimum value between 30 minutes; the sixth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the "maximum temperature difference in the thickness direction of the cable structure" ΔT _tmax is not greater than 1 degree Celsius; this method utilizes the above six conditions, and the following Any one of the three kinds of time is called "mathematical time for obtaining the steady-state temperature data of the cable structure". Item 1 to item 5 conditions, the second type of time is the time that only meets the sixth condition in the above "conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure", and the third type of time is when the above-mentioned conditions are met at the same time The moment of the first item to the sixth condition in "Conditions related to the moment of determining the time to obtain the steady-state temperature data of the cable structure"; For one hour, the moment of obtaining the steady-state temperature data of the cable structure is the mathematical moment of obtaining the steady-state temperature data of the cable structure; Take the method closest to the mathematical moment of obtaining the steady-state temperature data of the cable structure The moment when the data is actually recorded is the moment when the steady-state temperature data of the cable structure is obtained; this method will use the amount measured and recorded at the moment when the steady-state temperature data of the cable structure is obtained to perform cable structure-related health monitoring analysis; this method approximately considers that the obtained cable structure The temperature field of the cable structure at the moment of the steady-state temperature data is in a steady state, that is, the temperature of the cable structure at this moment does not change with time, and this moment is the "moment of obtaining the steady-state temperature data of the cable structure" of this method; Thermal characteristics, using the "measured surface temperature data of R cable structures" and "measured data of temperature along the thickness of HBE cable structures" at the time when the steady-state temperature data of cable structures are obtained, using the heat transfer calculation model of cable structures, through conventional The thermal calculation obtains the temperature distribution of the cable structure at the moment when the steady-state temperature data of the cable structure is obtained. At this time, the temperature field of the cable structure is calculated according to the steady state. The temperature distribution data includes the calculated temperature of R cable structure surface points on the cable structure, and the calculated temperature of the R cable structure surface points is called the R cable structure steady-state surface temperature calculation data, and also includes the HBE selected in front of the cable structure. The calculation temperature of "points for measuring the temperature distribution data of the cable structure along the thickness", the calculation temperature of HBE "points for measuring the temperature distribution data of the cable structure along the thickness" is called "HBE temperature calculation data of the cable structure along the thickness", when When the measured data of the surface temperature of R cable structures is equal to the calculated data of the steady-state surface temperature of R cable structures, and the "measured data of the temperature along the thickness of the HBE cable structures" is correspondingly equal to the "calculated data of the temperature along the thickness of the HBE cable structures" , the calculated temperature distribution data of the cable structure at the moment when the cable structure steady-state temperature data is obtained is called "cable structure steady-state temperature data" in this method, and the "R cable structure surface temperature measured data" at this time is called is the "measured data of the steady-state surface temperature of R cable structures", and the "measured data of the temperature of the HBE cable structures along the thickness" is called "the measured data of the steady-state temperature of the HBE cable structures along the thickness"; cable structure surface points", the number and distribution of "R cable structure surface points" must meet three conditions. The first condition is that when the cable structure temperature field is in a steady state, when the temperature of any point on the cable structure surface When it is obtained by the linear interpolation of the measured temperature of the point adjacent to the arbitrary point on the surface of the cable structure among the "R cable structure surface points", the temperature of the arbitrary point on the surface of the cable structure obtained by linear interpolation is the same as the temperature of the arbitrary point on the surface of the cable structure The error of the actual temperature at any point is not greater than 5%; the surface of the cable structure includes the surface of the supporting cable; the second condition is that the number of points at the same altitude in the "R cable structure surface points" is not less than 4, and "R The points at the same altitude in "Cable Structure Surface Points" are evenly distributed along the cable structure surface; the absolute value of the difference in altitude between all pairwise adjacent cable structure surface points along the altitude of "R Cable Structure Surface Points" The maximum value of Δh is not greater than 0.2°C divided by ΔT _h . For the convenience of description, the unit of ΔT _h is ℃/m. For the convenience of description, the unit of Δh is m; "R The definition of two adjacent cable structure surface points along the altitude of the cable structure surface point means that when only the altitude is considered, there is no cable structure surface point in the "R cable structure surface points", and the cable structure surface point The altitude value of the cable structure is between the altitude values of two adjacent cable structure surface points; the third condition is to query or calculate according to meteorological routines to obtain the sunshine law of the cable structure location and the altitude interval, and then according to the cable structure Geometric features and azimuth data, find the positions of those surface points on the cable structure that receive the most sunshine time throughout the year, at least one cable structure surface point in the "R cable structure surface points" is the annual sunshine time on the cable structure one of those surface points that is most adequate;

c. According to the "temperature measurement and calculation method of the cable structure of this method", the steady-state temperature data of the cable structure in the initial state is directly measured and calculated, and the steady-state temperature data of the cable structure in the initial state is called the initial steady-state temperature data of the cable structure. It is recorded as "initial cable structure steady-state temperature data vector T _o "; the physical and mechanical performance parameters of various materials used in the cable structure _that vary with temperature are obtained from actual measurements or information; At the same moment when the steady-state temperature data vector T _o of the initial cable structure is obtained, the measured data of the initial cable structure are directly measured and calculated. The measured data of the initial cable structure include the non-destructive testing data expressing the health Initial generalized displacement measurement data, initial values of all monitored quantities, initial cable force data of all supporting cables, initial cable structure modal data, initial cable structure strain data, initial cable structure geometric data, initial cable structure support generalized coordinate data , the initial cable structure angle data, the initial cable structure space coordinate data; the initial values of all the monitored quantities form the initial numerical vector C _o of the monitored quantities, the numbering rule of the initial numerical vector C _o of the monitored quantities and the numbers of the M monitored quantities The rules are the same; the initial damage vector d _o of the evaluated object is established by using the non-destructive testing data that can express the health state of the supporting cable and the initial generalized displacement measurement data of the cable structure support, and the vector d _o represents the cable represented by the initial mechanical calculation benchmark model A _o The initial health state of the evaluated object of the structure; the number of elements of the evaluated object’s initial damage vector d _o is equal to N, and the elements of d _o have a one-to-one correspondence with the evaluated object, and the numbering rules of the elements of the vector d _o are the same as the evaluated The numbering rules of the objects are the same; if a certain element of d _o corresponds to a supporting cable in the cable system, then the value of this element of d _o represents the initial damage degree of the corresponding supporting cable, if the value of the element If it is 0, it means that the supporting cable corresponding to this element is intact and not damaged; if its value is 100%, it means that the supporting cable corresponding to this element has completely lost its bearing capacity; if its value is between 0 and 100% between, it means that the supporting cable has lost the bearing capacity of the corresponding proportion; if a certain element of d _o corresponds to a certain generalized displacement component of a certain support, then the value of the element of d _o represents the The initial value of the generalized displacement component of the support; if there is no non-destructive testing data of the supporting cable and other data that can express the health state of the supporting cable, or it can be considered that the initial state of the structure is a state of no damage and no relaxation, in the vector d _o The value of each element related to the supporting cable is taken as 0. If there is no initial generalized displacement measurement data of the cable structure support or it can be considered that the initial generalized displacement of the cable structure support is 0, each element related to the generalized displacement of the cable structure support in the vector d _o The value of the element is taken as ₀ ; the initial generalized coordinate data of the cable structure support refers to the support coordinate data under the design state of the cable structure, and the initial generalized displacement measurement data of the cable structure support refers to the The generalized displacement of the seat relative to the support in the design state of the cable structure; the generalized coordinates of the support include two types: linear and angular;

d. According to the design drawing of the cable structure, the as-built drawing and the actual measurement data of the initial cable structure, the non-destructive testing data of the supporting cable, the initial generalized displacement measurement data of the support of the cable structure, and the temperature-dependent physical properties of various materials used in the cable structure Based on the mechanical performance parameters, the initial cable structure steady-state temperature data vector T _o and all the cable structure data obtained in the previous steps, establish the initial mechanical calculation benchmark model A _o of the cable structure that includes the "cable structure steady-state temperature data", The calculated data of the cable structure based on A _o must be very close to the measured data, and the difference between them should not be greater than 5%; the "cable structure steady temperature data" corresponding to A _o is the "initial cable structure steady temperature data vector T _o ”; the health status of the assessed object corresponding to A _o is expressed by the initial damage vector d _o of the assessed object; the initial values of all monitored quantities corresponding to A _o are expressed by the initial value vector C _o of the monitored quantities; the first establishment The current initial mechanical calculation benchmark model A ^t _o of the cable structure, the current initial value vector C ^t _o of the monitored quantity, and the "current initial cable structure steady-state temperature data vector T ^t _o " of the cable structure included in the "cable structure steady-state temperature data"; When the current initial mechanical calculation benchmark model A ^t _o of the cable structure and the current initial numerical vector C ^t _o of the monitored quantity are established for the first time, the current initial mechanical calculation benchmark model A ^t _o of the cable structure is equal to the initial mechanical calculation benchmark of the cable structure For model A _o , the current initial numerical vector C ^t _o of the monitored quantity is equal to the initial numerical vector C _o of the monitored quantity; the "steady-state temperature data of the cable structure" corresponding to A ^t _o is called "the current initial steady-state temperature data of the cable structure" , recorded as "the current initial cable structure steady-state temperature data vector T ^t _o ", when the current initial mechanical calculation benchmark model A ^t _o of the cable structure is established for the first time, T ^t _o is equal to T _o ; A ^t _o is evaluated The initial health state of the object is the same as the health state of the evaluated object of A _o , and is also expressed by the initial damage vector d _o of the evaluated object. In the subsequent cycle process, the initial health state of the evaluated object of A ^t _o is always represented by The initial damage vector d _o of the object is represented; T _o and d _o are the parameters of A _o , and the initial values of all the monitored quantities obtained from the mechanical calculation results of A _o are the same as the initial values of all the monitored quantities represented by C _o , so It can also be said that C _o is composed of the mechanical calculation results of A _o ; T ^t _o and d _o are the parameters of A ^t _o , and C ^t _o is composed of the mechanical calculation results of A ^t _o ;

e. From here, enter the cycle from step e to step m; during the service process of the structure, continuously measure and calculate according to "the temperature measurement and calculation method of the cable structure of this method" to obtain the current value of the "steady-state temperature data of the cable structure" data, the current data of "cable structure steady-state temperature data" is called "current cable structure steady-state temperature data", recorded as "current cable structure steady-state temperature data vector T ^t ", the definition of vector T ^t is the same as that of vector T _o are defined in the same way; while obtaining the steady-state temperature data vector T ^t of the current cable structure, non-destructive testing is carried out on the newly added M ₂ sensing cables, and the damaged or loose sensing cables are identified. Quantity numbering rules, remove the elements corresponding to the identified damage or slack sensor cables from the vectors numbered according to the monitored quantity numbering rules that appear before this method, and also in each vectors and matrices that appear after this method The elements corresponding to the identified damaged or loose sensory cables no longer appear. When referring to the sensory cables after this method, the sensory cables that are identified as damaged or loose here are no longer included. When it comes to the monitored quantity, it no longer includes the cable force of the sensor cables that are identified as being damaged or slack here; if several sensor cables that are damaged or slack are identified from the cable structure, M ₂ and M are reduced by the same quantity;

f. According to the current cable structure steady-state temperature data vector T ^t , follow steps f1 to f3 to update the current initial mechanical calculation benchmark model A ^t _o , the current initial value vector C ^t _o of the monitored quantity and the current initial cable structure steady-state temperature data vector T ^t _o ;

f1. Compare T ^t and T ^t _o , if T ^t is equal to T ^t _o , then A ^t _o , C ^t _o and T ^t _o remain unchanged; otherwise, follow the steps below to adjust A ^t _o , U ^t _o and T ^t _o update;

f2. Calculate the difference between T ^t and T _o . The difference between T ^t and T _o is the change of the current cable structure steady-state temperature data with respect to the initial cable structure steady-state temperature data. The difference between T ^t and T _o uses the steady-state temperature change vector S means that S is equal to T ^t minus T _o , and S means the change of the steady-state temperature data of the cable structure;

f3. Apply temperature changes to the cable structure in A _o , the value of the applied temperature change is taken from the steady-state temperature change vector S, and the updated current initial mechanical calculation benchmark model is obtained after the temperature change is applied to the cable structure in A _o A ^t _o , when A ^t _o is updated, all element values of T ^t _o are replaced by corresponding values of all elements of T ^t , that is, T ^t _o is updated, so that T ^t _o corresponding to A ^t _o is obtained ; The method to update C ^t _o is: when A ^t _o is updated, the current specific values of all the monitored quantities in A ^t _o are obtained through mechanical calculations ^, and these specific values form C ^t _{o ;} The initial health state is always represented by the initial damage vector d _o of the evaluated object;

g. On the basis of the current initial mechanical calculation benchmark model A ^t _o , perform several mechanical calculations according to steps g1 to g4, and obtain the unit change matrix ΔC of the unit damage of the cable structure and the unit damage or unit generalized displacement vector D _u through calculation ;

g1. The unit change matrix ΔC of the unit damage of the cable structure and the monitored quantity is constantly updated, that is, the current initial mechanical calculation benchmark model A ^t _o , the current initial value vector C ^t _o of the monitored quantity and the current initial steady-state temperature data of the cable structure are updated. After the vector T ^t _o , it is necessary to update the unit change matrix ΔC of the unit damage of the cable structure and the unit damage or unit generalized displacement vector D _u ;

g2. Carry out several mechanical calculations on the basis of the current initial mechanical calculation benchmark model A ^t _o of the cable structure. The number of calculations is numerically equal to the number N of all evaluated objects. There are N evaluation objects and there are N calculations; The numbering rules of the evaluation objects are calculated sequentially; each calculation assumes that there is only one evaluated object, and the unit damage or unit generalized displacement is added on the basis of the original damage or generalized displacement. Specifically, if the evaluated object is a cable system A support cable, then it is assumed that the support cable increases the unit damage, if the evaluated object is a generalized displacement component of a support in one direction, it is assumed that the support increases the unit generalized displacement in the displacement direction, using D _uk records this increased unit damage or unit generalized displacement, where k represents the number of the assessed object that increased unit damage or unit generalized displacement, and D _uk is an element of the unit damage or unit generalized displacement vector D _u , unit damage or unit The numbering rule of the elements of the generalized displacement vector D _u is the same as the numbering rule of the elements of the vector d _o ; the evaluated object of increasing unit damage or unit generalized displacement in each calculation is different from that of increasing unit damage or unit generalized displacement in other calculations For the evaluated object, each calculation uses the mechanical method to calculate the current calculated value of all the monitored quantities of the cable structure, and the current calculated values of all the monitored quantities obtained by each calculation form a current vector for the calculation of the monitored quantity, and the calculation of the monitored quantity The element numbering rule of the current vector is the same as the element numbering rule of the initial value vector C _o of the monitored quantity;

g3. Calculate the current vector of the monitored quantity obtained by each calculation and subtract the current initial value vector C ^t _o of the monitored quantity to obtain a vector, and then divide each element of the vector by the unit damage or unit assumed for this calculation Generalized displacement value, get a unit change vector of the monitored quantity, if there are N evaluated objects, there will be N unit change vectors of the monitored quantity;

g4. According to the numbering rules of the N evaluated objects, the N monitored quantity unit change vectors are sequentially formed into a cable structure unit damage monitored quantity unit change matrix ΔC with N columns; a cable structure unit damage monitored quantity unit change matrix Each column of ΔC corresponds to a monitored quantity unit change vector; each row of the cable structure unit damage monitored quantity unit change matrix ΔC corresponds to the difference of the same monitored quantity when different evaluated objects increase unit damage or unit generalized displacement The unit change range of the cable structure unit damage monitored quantity unit change matrix ΔC is the same as the numbering rule of the elements of the vector d _o , and the row numbering rule of the cable structure unit damage monitored quantity unit change matrix ΔC is the same as M The numbering rules of the monitored quantities are the same;

h. Obtaining the current measured values of all monitored quantities of the cable structure at the same moment when the current cable structure steady-state temperature data vector ^{T t is} obtained through actual measurement, Composing the current numerical vector C of the monitored quantity; the current numerical vector C of the monitored quantity and the current initial numerical vector C ^t _o of the monitored quantity are defined in the same way as the initial numerical vector C _o of the monitored quantity, and the elements of the same number of the three vectors represent Specific values of the same monitored quantity at different times;

i. Define the current nominal damage vector d of the evaluated object, the number of elements of the current nominal damage vector d of the evaluated object is equal to the number of evaluated objects, and the elements of the current nominal damage vector d of the evaluated object and the evaluated object are one by one Corresponding relationship, the element value of the current nominal damage vector d of the evaluated object represents the nominal damage degree or nominal generalized displacement of the corresponding evaluated object; the numbering rule of the elements of the vector d is the same as that of the elements of the vector d _o ;

j. According to the current numerical vector C of the monitored quantity and the current initial numerical vector C ^t _o of the monitored quantity, the cable structure unit damage unit change matrix ΔC of the monitored quantity, the unit damage or unit generalized displacement vector D _u and the evaluated object to be obtained The approximate linear relationship between the current nominal damage vectors d can be expressed as formula 1. In formula 1, other quantities except d are known, and the current nominal damage vector d of the evaluated object can be calculated by solving formula 1 ;

$C=C_o^t+\mathrm{\&Delta;C}\&Center\; Dot;d$ Formula 1

k. Define the current actual damage vector d ^a of the evaluated object, the number of elements of the current actual damage vector d ^a of the evaluated object is equal to the number of evaluated objects, and the distance between the elements of the current actual damage vector d ^a of the evaluated object and the evaluated object It is a one-to-one correspondence relationship, the element value of the current actual damage vector d ^a of the evaluated object represents the actual damage degree or actual generalized displacement of the corresponding evaluated object; the numbering rule of the elements of the vector d ^a is the same as that of the elements of the vector d _o ;

l. The k-th element d ^a _k of the current actual damage vector d ^a of the evaluated object expressed by formula 2 is the same as the k-th element d _ok of the initial damage vector d _o of the evaluated object and the current nominal damage vector d of the evaluated object The relationship between the kth element d _k is calculated to obtain all the elements of the current actual damage vector d ^a of the evaluated object;

Formula 2

In formula 2, k=1,2,3,......,N, d ^a _k represents the current actual health status of the kth evaluated object, if the evaluated object is a support in the cable system Then d ^a _k represents its current actual damage. When d ^a _k is 0, it means no damage. When it is 100%, it means that the supporting cable completely loses its bearing capacity. When it is between 0 and 100%, it means that it loses the corresponding proportion of bearing capacity. capacity, if the evaluated object is a generalized displacement component of a support, then d ^a _k represents its current actual generalized displacement value; therefore, according to the current actual damage vector d ^a of the evaluated object, it can be determined which supporting cables are damaged and their Damage degree, to determine which supports have undergone generalized displacement and their values, that is, to realize the identification of damaged cables and support generalized displacements of cable structures;

m. Go back to step e and start the next cycle from step e to step m.

Beneficial effects: When the temperature field of the cable structure is affected by factors such as sunshine and ambient temperature, the temperature field of the cable structure is constantly changing, and the change of the temperature field of the cable structure will inevitably affect the monitored quantity of the cable structure. Only the monitored quantity will be affected Reasonable structural health monitoring based on the monitored quantity can be carried out only by removing the influence of the temperature field. However, the temperature field measurement and calculation of cable structures are very complicated. This method discloses a simple and economical method suitable for structural health monitoring. , Feasible and efficient calculation method of structural temperature field for cable structure health monitoring method, using this method in the case of generalized displacement of the cable structure support, when multiple cables of the cable structure are damaged synchronously, and the temperature of the cable structure When changing over time, the generalized displacement of damaged cables and supports can be monitored and evaluated very accurately, and the system and method disclosed in the present method are very beneficial for effective health monitoring of cable structures.

Detailed ways

When the temperature changes, the method discloses a system and method capable of reasonably and effectively monitoring and identifying the health status of each evaluated object in the cable structure for the generalized displacement identification of damaged cables and supports of the cable structure. The following description of embodiments of the method is merely exemplary in nature and is in no way intended to limit the application or uses of the method.

This method employs an algorithm that is used to identify damaged cables and support generalized displacements. During specific implementation, the following steps are one of various steps that may be taken.

Step 1: Let the sum of the number of supporting cables of the cable structure and the number of generalized displacement components of the support of the cable structure be N. For the convenience of description, this method collectively refers to the evaluated support cables and support generalized displacements as "evaluated objects", and there are N evaluated objects. Consecutively number the evaluated objects, which will be used to generate vectors and matrices in subsequent steps.

Assuming that there are M ₁ supporting cables in the cable system, the structural cable force data includes the cable force of these M ₁ supporting cables, obviously M ₁ is smaller than the number N of the evaluated objects. It is impossible to solve the unknown state of N evaluated objects only by M ₁ cable force data of M ₁ supporting cables. On the basis of monitoring all M ₁ supporting cable forces, this method adds no less than (NM ₁ ) other monitored quantities.

The other monitored quantities increased by not less than (NM ₁ ) are still cable forces, described as follows:

Before the structural health detection system starts to work, artificially add M ₂ (M ₂ is not less than NM ₁ ) cables on the cable structure, which are called sensing cables. The stiffness of the newly added M ₂ sensing cables is the same as that of the cable structure. Compared with the stiffness of any supporting cable, it should be much smaller, such as 20 times smaller, and the cable force of the newly added M ₂ sensing cables should be smaller, for example, the normal stress of its cross section should be less than its fatigue limit, these requirements can be Ensure that the newly added M ₂ sensing cables will not suffer from fatigue damage, the two ends of the newly added M ₂ sensing cables should be fully anchored to ensure that there will be no slack, and the newly added M ₂ sensing cables should be fully anchored. The anti-corrosion protection ensures that the newly added M ₂ sensing cables will not be damaged and slack, and the cable force of the newly added M ₂ sensing cables will be monitored during the structural health monitoring process.

It is also possible to increase the reliability of health monitoring by adding more sensing cables, for example, make M ₂ not less than twice NM ₁ , and only select the cable force data of intact sensing cables in the process of structural health monitoring ( It is called the actual monitored quantity that can be used, and its quantity is recorded as K, K must not be less than N) and the corresponding cable structure monitored quantity unit change matrix ΔC for health status assessment. Since M ₂ is not less than 2 times of NM ₁ , it can be Ensure that the number of effective sensing cables that can actually be used plus M1 is not less _than N. The cable force of the newly added M ₂ sensing cables will be monitored during the structural health monitoring process. The newly added M ₂ sensing cables should be installed on the structure, where personnel can easily reach, so that personnel can conduct non-destructive testing on it.

In this method, the newly added M ₂ sensing cables are used as part of the cable structure. When referring to the cable structure later, the cable structure includes the cable structure before adding the M ₂ sensing cables and the newly added M ₂ The sense cable, that is to say, when the cable structure is mentioned later, refers to the cable structure including the newly added _M2 sensing cables. Therefore, when it is mentioned later that the "cable structure steady-state temperature data" is measured and calculated according to "the temperature measurement and calculation method of the cable structure of this method", the cable structure includes newly added _M2 sensing cables, and the obtained "cable structure The "structure steady-state temperature data" includes the steady-state temperature data of the newly added M ₂ sensing cables, and the method of obtaining the steady-state temperature data of the newly added M ₂ sensing cables is the same as that of the M ₁ supporting cables of the cable structure. The method of obtaining the steady-state temperature data will not be explained in the following text; the method of measuring the cable force of the newly added M ₂ sensing cables is the same as the method of measuring the cable force of the M ₁ supporting cables of the cable structure, It will not be explained one by one in the following text; when any measurement is carried out on the supporting cables of the cable structure, the same measurement will be carried out on the newly added M ₂ sensing cables, which will not be explained one by one in the following text; the newly added M ₂ In addition to no damage and slack in the root sensing cable, the information volume of the newly added M ₂ cables is the same as that of the supporting cable of the cable structure, which will not be explained one by one in the following; the newly added M ₂ sensor cables The cable force of the cable is the addition of not less than (NM ₁ ) other monitored quantities. When establishing various mechanical models of the cable structure later, the newly added M ₂ sensing cables are treated as the M ₁ supporting cables of the cable structure. References to support cables include the newly added M ₂ cables.

Based on the above-mentioned monitored quantities, the entire cable structure has M monitored quantities of M (M=M ₁ +M ₂ ) cables, and M must not be less than the number N of evaluated objects.

For convenience, in this method, "all monitored parameters of the cable structure" are referred to as "monitored quantities" for short. Number the M monitored quantities consecutively, and this number will be used to generate vectors and matrices in subsequent steps. The method uses variable j to denote this number, j=1,2,3,...,M.

Determine "the temperature measurement and calculation method of the cable structure of this method", the specific steps of the method are as follows:

Step a: Query or actual measurement (can be measured by conventional temperature measurement methods, for example, using thermal resistance measurement) to obtain the heat transfer parameters of the composition materials of the cable structure and the environment where the cable structure is located, which vary with temperature, and use the design drawing of the cable structure, The as-built drawing and the geometrically measured data of the cable structure are used to establish a heat transfer calculation model (such as a finite element model) of the cable structure using these data and parameters. Query the meteorological data of not less than 2 years at the location of the cable structure in recent years, and the number of cloudy days during this period is counted as T cloudy days, and the statistics are obtained from 0:00 to the next day of each cloudy day in the T cloudy days The highest temperature and the lowest temperature between 30 minutes after sunrise time. Sunrise time refers to the meteorological sunrise time determined according to the earth's rotation and revolution laws. You can query the data or calculate the required daily temperature by conventional meteorology. At the sunrise time of a day, the maximum temperature minus the minimum temperature between 0:00 on each cloudy day and 30 minutes after the sunrise time of the next day is called the maximum temperature difference of the daily temperature of the cloudy day. There are T cloudy days, There are T maximum temperature differences of daily air temperature on cloudy days, and the maximum value among the maximum temperature differences of T cloudy days is taken as the reference daily temperature difference, and the reference daily temperature difference is denoted as ΔT _r ; Meteorological data of less than 2 years in recent years or the change data and change law of the temperature of the environment where the cable structure is located with time and altitude obtained from actual measurements, and the calculation of the location and altitude of the cable structure in recent years is not less than 2 years The temperature of the environment where the cable structure is located is the maximum change rate ΔT _h with respect to the altitude. For the convenience of description, the unit of ΔT _h is ℃/m; The specific principle of the surface point of the cable structure” is described in step b3. The temperature of the R surface points of the cable structure will be obtained through the actual measurement record later, and the temperature data obtained from the actual measurement is called “the measured data of the surface temperature of the R cable structure”. If it is Using the heat transfer calculation model of the cable structure, the temperature of the R cable structure surface points is obtained through heat transfer calculation, and the calculated temperature data is called "R cable structure surface temperature calculation data". From the lowest altitude to the highest altitude where the cable structure is located, select no less than three different altitudes evenly on the cable structure, for example, if the altitude of the cable structure is between 0m and 200m, then you can choose an altitude of 0m . Select 6 points at the intersection of the horizontal plane and the surface of the cable structure, and index the outer normal of the surface of the structure from the selected points. The direction of all selected outer normals is called "the direction of measuring the temperature distribution of the cable structure along the wall thickness", The direction of measuring the temperature distribution of the cable structure along the wall thickness intersects the "line of intersection between the horizontal plane and the surface of the cable structure". Among the six directions selected for measuring the temperature distribution of the cable structure along the wall thickness, the cable structure is first determined according to the meteorological data of the year and the seasons in the area where the cable structure is located, the geometric dimensions, spatial coordinates, and the surrounding environment of the cable structure, etc. The sunny side and the shady side of the cable structure, the sunny side and the shady side of the cable structure are part of the surface of the cable structure. At each selected altitude, the aforementioned intersection line has a section in the sunny side and the shady side. There is a midpoint in each of the two sections, and the outer normal of the cable structure is obtained through these two midpoints. In this method, these two outer normals are called the outer normal of the sunny surface of the cable structure and the outer normal of the shady surface of the cable structure. , this method refers to these two outer normal directions as the outer normal direction of the sunny surface of the cable structure and the outer normal direction of the shady surface of the cable structure. Obviously, the outer normal of the sunny surface and the outer normal of the shady surface are the same When the intersection line intersects, there are two intersection points. These two intersection points divide the intersection line into two line segments. Take 2 points on the two line segments respectively, a total of 4 points, and the points will be the two line segments of the intersection line. Each line segment in is divided into 3 segments of equal length, and the external normals of the surface of the cable structure are obtained at these 4 points, so that a total of 6 external normals of the surface of the cable structure are selected at each selected altitude. The directions of the 6 outer normals are "directions for measuring the temperature distribution of the cable structure along the wall thickness". Each "direction for measuring the temperature distribution of the cable structure along the wall thickness" line has two intersection points with the surface of the cable structure. If the cable structure is hollow, one of the two intersection points is on the outer surface of the cable structure and the other is on the inner surface. If the cable structure is solid, the two intersection points are on the outer surface of the cable structure, and a straight line segment is obtained by connecting these two intersection points, and three points are selected on the straight line segment, and these three points will equalize the straight line segment Divided into four sections, measure the temperature of the cable structure at the selected three points and the two end points of the straight section, a total of 5 points. Specifically, you can drill holes in the cable structure first, and bury the temperature sensor at these 5 points. In particular, holes cannot be drilled on the support cable, and only the temperature at the surface point of the support cable is measured for the support cable. In any case, the measured temperature is called the "temperature distribution data of the cable structure along the thickness" at this place, where The "temperature distribution data of the cable structure along the thickness" measured by the "direction of measuring the temperature distribution of the cable structure along the wall thickness" intersecting with the same "intersection line between the horizontal plane and the surface of the cable structure" is called "the same Temperature distribution data along the thickness of cable structures at altitude". Assuming that H different altitudes are selected, at each altitude, B are selected to measure the temperature distribution direction of the cable structure along the wall thickness, and along the direction of the temperature distribution of each measurement cable structure along the wall thickness in the cable structure E points are selected in , where H and E are not less than 3, and B is not less than 2. In particular, for the supporting cable E is equal to 1, the total number of "points for measuring the temperature distribution data of the cable structure along the thickness" on the cable structure It is HBE, and the temperature of these HBE "points for measuring the temperature distribution data of the cable structure along the thickness" will be obtained through actual measurement later. The heat transfer calculation model of the cable structure, through the heat transfer calculation, the temperature of the point where the temperature distribution data of the HBE cable structure is measured along the thickness is obtained, and the calculated temperature data is called "the temperature calculation data of the HBE cable structure along the thickness" In this method, the number temperature distribution data of "the temperature distribution data of the same altitude cable structure along the thickness" will be at each selected altitude. At the location of the cable structure, a position is selected according to the meteorological temperature measurement requirements, and will be in The actual measurement record at this location obtains the temperature of the environment where the cable structure is located that meets the requirements of meteorological temperature measurement; select a location in an open and unsheltered place where the cable structure is located, and this location should be able to get what the location can get every day of the year. The fullest sunshine of the day (as long as there is sunrise on that day, the position should be irradiated by the sun), place a flat plate of carbon steel (such as No. 45 carbon steel) (such as a 30cm wide and 3mm thick square The reference plate is called the reference plate. The reference plate cannot be in contact with the ground. The distance between the reference plate and the ground is not less than 1.5 meters. The reference plate can be placed on the top of a wooden shutter box that meets the meteorological temperature measurement requirements. , called the sunny side (for example, in the northern hemisphere, the sunny side faces up and faces south, and is exposed to sunlight throughout the day, and the sunny side should have an appropriate slope so that snow cannot accumulate or clean up the sunny side after snow), refer to the sunny side of the flat plate It is rough and dark (good for receiving sunlight), and the sunny side of the reference plate should be able to get the fullest sunlight that a plate can get on that day on every day of the year. The reference plate The non-sun-facing side of the slab is covered with thermal insulation material (such as 5mm thick calcium carbonate thermal insulation material), and the temperature of the sunny side of the reference plate will be obtained by real-time monitoring and recording.

Step b, real-time monitoring (can be measured with conventional temperature measurement methods, such as using thermal resistance measurement, such as measuring and recording temperature data every 10 minutes) record the measured data of the R cable structure surface temperature of the above R cable structure surface points , while real-time monitoring (can be measured with conventional temperature measurement methods, for example, using thermal resistance measurement, such as measuring and recording temperature data every 10 minutes) to obtain the temperature distribution data of the cable structure defined above along the thickness, while real-time monitoring (can be measured with conventional Temperature measurement method measurement, such as placing a thermal resistance in a wooden shutter that meets the meteorological temperature measurement requirements to measure the temperature, such as measuring and recording temperature data every 10 minutes) to record the environment where the cable structure meets the meteorological temperature measurement requirements Air temperature data; through real-time monitoring (it can be measured by conventional temperature measurement methods, such as placing a thermal resistance in a wooden shutter that meets the meteorological temperature measurement requirements to measure the temperature, such as measuring and recording temperature data every 10 minutes) to record and obtain the current day The temperature measured data series of the environment where the cable structure is located between the departure time and 30 minutes after the sunrise time of the next day, and the temperature measured data series of the environment where the cable structure is located from the sunrise time of the day to 30 minutes after the sunrise time of the next day The measured temperature data of the environment where the cable structure is located is arranged in chronological order, and the highest temperature and the lowest temperature in the measured data sequence of the temperature of the environment where the cable structure is located are found, and the minimum temperature is subtracted from the highest temperature in the measured data sequence of the temperature of the environment where the cable structure is located Obtain the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day in the environment where the cable structure is located, and record it as ΔT _emax ; the measured data sequence of the temperature in the environment where the cable structure is located is calculated by conventional mathematics (for example, first for the cable structure Curve fitting is performed on the temperature measured data series in the environment, and then by calculating the derivative of the curve with respect to time or by using numerical methods to calculate the rate of change of each point on the curve corresponding to the time of the measurement record data to time) to obtain the environment where the cable structure is located The rate of change of air temperature with respect to time, the rate of change also changes with time; through real-time monitoring (can be measured by conventional temperature measurement methods, such as using thermal resistance to measure the temperature of the sunny side of the reference plate, such as measuring and recording temperature data every 10 minutes ) to obtain the measured data sequence of the temperature of the sunny side of the reference plate between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, and the measured data series of the temperature of the sunny side of the reference plate from the sunrise time of the current day to the next day The measured data of the temperature on the sunny side of the reference plate between 30 minutes after the time of departure is arranged in chronological order, find the highest temperature and the lowest temperature in the sequence of measured data of the temperature on the sunny side of the reference plate, use the sunny side of the reference plate The maximum temperature in the measured data sequence of the temperature minus the minimum temperature obtains the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day of the temperature of the sunny side of the reference plate, which is recorded as ΔT _pmax ; through real-time monitoring (It can be measured with conventional temperature measurement methods, such as using thermal resistance measurement to measure the surface point of the cable structure, such as every 10 minutes Measure and record the temperature data once) record the measured data sequence of the cable structure surface temperature of all R cable structure surface points between the sunrise time of the day and 30 minutes after the next day’s sunrise time, there are R cable structure surface points and there are R Each cable structure surface temperature measured data sequence, each cable structure surface temperature measured data sequence is from the sunrise time of a cable structure surface point on the same day to the cable structure surface temperature measured data 30 minutes after the next day's sunrise time in chronological order Arrange in order, find the highest temperature and the lowest temperature in the measured data sequence of the surface temperature of each cable structure, subtract the lowest temperature from the highest temperature in the measured data sequence of the surface temperature of each cable structure to obtain the temperature of each cable structure surface point of the day The maximum temperature difference between the sunrise time and 30 minutes after the next day's sunrise time, there are R cable structure surface points, there are R maximum temperature difference values between the current day's sunrise time and the next day's sunrise time 30 minutes, of which The maximum value of ΔT smax is recorded as ΔT _smax ; from the measured data series of the surface temperature of each cable structure through conventional mathematical calculation (for example, curve fitting is first performed on the measured data series of the surface temperature of each cable structure, and then by calculating the derivative of the curve with respect to time or by Use the numerical method to calculate the rate of change of each point on the curve corresponding to the time of the measurement record data to time) to obtain the temperature change rate of each cable structure surface point with respect to time, and the temperature change rate of each cable structure surface point with respect to time Also changes over time. After obtaining HBE "temperature distribution data along the thickness of the cable structure" at the same time between the sunrise time of the day and 30 minutes after the next day's sunrise time through real-time monitoring, calculate the total BE at each selected altitude. The difference between the highest temperature and the lowest temperature in the "temperature distribution data of the cable structure along the thickness at the same altitude", the absolute value of this difference is called "the maximum temperature difference in the thickness direction of the cable structure at the same altitude", H There are H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" at different altitudes, and the maximum value of the H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" is "the maximum temperature difference in the thickness direction of the cable structure" , recorded as ΔT _tmax .

Step c, measure and calculate the steady-state temperature data of the cable structure; firstly, determine the time to obtain the steady-state temperature data of the cable structure, and there are six conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure, the first condition is The time to obtain the steady-state temperature data of the cable structure is between the sunset time of the day and 30 minutes after the sunrise time of the next day. The sunset time refers to the meteorological sunset time determined according to the laws of the earth's rotation and revolution. You can query the data or pass The required sunset time of each day is calculated by conventional meteorology; the second condition a condition is that during the period between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, ΔT _pmax and ΔT _smax Neither is greater than 5 degrees Celsius; the second condition that must be met is that the ΔT _emax obtained from the previous measurement and calculation is not greater than the reference daily temperature difference during the period between the sunrise of the current day and 30 minutes after the sunrise of the next day ΔT _r , and the ΔT _pmax obtained in the previous measurement minus 2 degrees Celsius is not greater than ΔT _emax , and the ΔT _smax obtained in the previous measurement and calculation is not greater than ΔT _pmax ; only one of the conditions a and b of the second item must be met Item is called to meet the second condition; the third condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of the environment where the cable structure is located with respect to time is not greater than 0.1 degrees Celsius per hour; the fourth condition The condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of each cable structure surface point in the R cable structure surface points with respect to time is not greater than 0.1 degrees Celsius per hour; the fifth condition is at At the time when the steady-state temperature data of the cable structure is obtained, the measured data of the surface temperature of the cable structure at each of the R cable structure surface points is the minimum value between the sunrise time of the day and 30 minutes after the sunrise time of the next day. value; the sixth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the "maximum temperature difference in the thickness direction of the cable structure" ΔT _tmax is not greater than 1 degree Celsius. This method utilizes the above-mentioned six conditions, and any one of the following three times is called "mathematical time for obtaining the steady-state temperature data of the cable structure". The first to fifth conditions in the time-related conditions", the second time only meets the sixth condition in the above-mentioned "conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure" time, the third type of time is the time when the first to sixth conditions in the above "conditions related to the time to obtain the steady-state temperature data of the cable structure" are satisfied at the same time; It is one of the time of actually recording data in this method, the moment of obtaining the steady-state temperature data of the cable structure is the mathematical moment of obtaining the steady-state temperature data of the cable structure; if the mathematical moment of obtaining the steady-state temperature data of the cable structure is not the actual At any moment in the time of recording data, the moment of actually recording data which is the closest to the mathematical moment of obtaining the steady-state temperature data of the cable structure in this method is taken as the moment of obtaining the steady-state temperature data of the cable structure; this method will be used in obtaining The measured and recorded quantities of the steady-state temperature data of the cable structure are used for cable structure-related health monitoring analysis; this method approximately considers that the temperature field of the cable structure at the moment when the steady-state temperature data of the cable structure is obtained is in a steady state, that is, the temperature of the cable structure at this moment does not change with Time changes, this moment is the moment when the method obtains the steady-state temperature data of the cable structure; then, according to the heat transfer characteristics of the cable structure, the R cable structure surface temperature measured data and the "HBE The measured data of the temperature along the thickness of the cable structure", using the heat transfer calculation model of the cable structure (such as the finite element model), through the conventional heat transfer calculation (such as the finite element method) to obtain the cable structure at the moment when the steady-state temperature data of the cable structure is obtained The temperature distribution of the structure. At this time, the temperature field of the cable structure is calculated according to the steady state. The calculated temperature distribution data of the cable structure at the moment when the steady-state temperature data of the cable structure is obtained includes the calculation of R cable structure surface points on the cable structure Temperature, the calculated temperature of the R cable structure surface points is called the R cable structure steady-state surface temperature calculation data, which also includes the calculation of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness" selected in the front of the cable structure Temperature, the calculated temperature of HBE "points for measuring temperature distribution data of cable structures along the thickness" is called "calculated temperature data of HBE cable structures along the thickness", when the measured surface temperature data of R cable structures and the steady state of R cable structures When the surface temperature calculation data are equal, and the "HBE cable structure temperature measured data along the thickness" is correspondingly equal to the "HBE cable structure temperature calculation data along the thickness", the calculated temperature at the moment when the cable structure steady-state temperature data is obtained The temperature distribution data of the cable structure is called "the steady-state temperature data of the cable structure" in this method, and the "measured surface temperature data of the R cable structures" at this time is called "the measured data of the steady-state surface temperature of the R cable structures", and " HBE cable structure measured temperature data along the thickness" is called "HBE cable structure steady-state temperature measured data along the thickness". When taking "R cable structure surface points" on the surface of the cable structure, the quantity and distribution of "R cable structure surface points" must meet three conditions. The first condition is that when the temperature field of the cable structure is in a steady state, When the temperature of any point on the surface of the cable structure is obtained by linear interpolation of the measured temperature of the points adjacent to the point on the surface of the cable structure among the "R points on the surface of the cable structure", the temperature of any point on the surface of the cable structure obtained by linear interpolation The difference between the temperature of the point and the actual temperature of any point on the surface of the cable structure is not more than 5%; the surface of the cable structure includes the surface of the supporting cable; The number is not less than 4, and the points at the same altitude in the "R cable structure surface points" are evenly distributed along the cable structure surface; all pairwise adjacent cable structure surface points of the "R cable structure surface points" are along the altitude The maximum value Δh in the absolute value of the difference in altitude is not greater than the value obtained by dividing 0.2°C by ΔT _h . For the convenience of description, the unit of ΔT _h is ℃/m, and for the convenience of description, the unit of Δh is m; "R The definition of two adjacent cable structure surface points along the altitude refers to that when only the altitude is considered, there is no cable structure surface point in the "R cable structure surface points", and the cable structure surface The altitude value of the point is between the altitude values of two adjacent cable structure surface points; the third condition is to query or calculate according to meteorological routines to obtain the sunshine law of the cable structure location and the altitude interval, and then according to the cable structure The geometric characteristics and azimuth data of the cable structure are used to find the positions of the surface points on the cable structure that receive the most sunshine time throughout the year. At least one cable structure surface point in the "R cable structure surface points" is on the cable structure that receives the sunshine throughout the year. One of those surface points where time is most abundant.

The second step: establish the initial mechanical calculation benchmark model A _o .

When the cable structure is completed, or before the health monitoring (damaged cable identification) system is established, the "cable structure steady-state temperature data" is measured and calculated according to the "temperature measurement and calculation method for the cable structure of this method" (it can be obtained by using conventional temperature Measurement methods, such as thermal resistance measurement), the "cable structure steady-state temperature data" at this time is expressed by vector T _o , which is called the initial cable structure steady-state temperature data vector T _o . At the same time when T _o is obtained from the actual measurement, that is, at the same moment when the steady-state temperature data vector of the initial cable structure is obtained, the initial values of all monitored quantities of the cable structure are directly measured and calculated by conventional methods, and the initial values of the monitored quantities are formed Vector C _o .

In this method, the following method can be used to measure and calculate a certain measured quantity and monitored quantity (such as a cable structure) at the same moment when the steady-state temperature data vector of a certain (such as initial or current) cable structure is obtained. All monitored quantities of the structure) data: while measuring and recording the temperature (including the air temperature of the environment where the cable structure is located, the temperature of the sunny side of the reference plate and the surface temperature of the cable structure), for example, measuring and recording the temperature every 10 minutes, then At the same time, the data of a certain measured quantity and monitored quantity (for example, all monitored quantities of the cable structure) are also measured and recorded every 10 minutes. Once the time to obtain the steady-state temperature data of the cable structure is determined, the data of a certain measured quantity and monitored quantity (for example, all monitored quantities of the cable structure) at the same time as the time when the steady-state temperature data of the cable structure is obtained is called At the same moment when the steady-state temperature data of the cable structure is obtained, the data of a certain measured quantity and a certain monitored quantity obtained by a certain method are measured by a certain method.

The physical parameters (such as thermal expansion coefficient) and mechanical performance parameters (such as elastic modulus, Poisson's ratio) of various materials used in the cable structure that change with temperature are obtained by conventional methods (research data or actual measurement); At the same time as the steady-state temperature data vector T _o of the cable structure, that is, at the same moment when the steady-state temperature data of the cable structure is obtained, the actual measurement and calculation data of the cable structure are obtained by using conventional methods for actual measurement and calculation. The measured and calculated data of the cable structure includes the non-destructive testing data of the supporting cable and other data that can express the health state of the cable, the initial geometric data of the cable structure, the data of the cable force, the tension data of the tie rod, the generalized coordinate data of the initial cable structure support, the cable structure support Measured data such as initial generalized displacement measurement data, cable structure modal data, structural strain data, structural angle measurement data, and structural space coordinate measurement data. The initial generalized coordinate data of the cable structure support refers to the support coordinate data under the design state of the cable structure, and the initial generalized displacement measurement data of the cable structure support refers to the relative position of the cable structure support relative to the cable structure design when the initial mechanical calculation benchmark model A _o is established. The generalized displacement of the support in the state. The initial geometric data of the cable structure can be the spatial coordinate data of all cable end points plus the spatial coordinate data of a series of points on the structure, the purpose is to determine the geometric characteristics of the cable structure according to these coordinate data. For cable-stayed bridges, the initial geometric data can be the spatial coordinate data of all cable end points plus the spatial coordinate data of several points on both ends of the bridge, which is the so-called bridge type data. Using the non-destructive testing data of supporting cables and other data that can express the health status of supporting cables and the initial generalized displacement measurement data of cable structure supports to establish the initial damage vector d _o of the evaluated object (as shown in formula (1)), expressed by d _o The initial health state of the evaluated object of the cable structure (expressed by the initial mechanical calculation benchmark model A _o ). If there is no non-destructive testing data of the supporting cable and other data that can express the health state of the supporting cable, or when the initial state of the structure can be considered as a state of no damage and no relaxation, the value of each element related to the supporting cable in the vector d _o is set to 0 , if there is no measurement data of the initial generalized displacement of the cable structure support or it can be considered that the initial generalized displacement of the cable structure support is 0, the value of each element in the vector d _o related to the generalized displacement of the cable structure support is 0. Utilize the design drawing, as-built drawing of the cable structure, the measured data of the initial cable structure, the non-destructive testing data of the supporting cable, the physical and mechanical performance parameters of various materials used in the cable structure as a function of temperature, and the steady-state temperature data of the initial cable structure Vector T _o , use mechanical methods (such as finite element method) to include "cable structure steady-state temperature data" to establish the initial mechanical calculation benchmark model A _o .

No matter what method is used to obtain the initial mechanical calculation benchmark model A _o , the cable structure calculation data calculated based on A _{o must} be very Close to the measured data, the error is generally not greater than 5%. In this way, the calculation data of cable force, strain, shape and displacement of cable structure, angle data of cable structure, spatial coordinate data of cable structure, etc. under the simulated situation obtained by A _o calculation can be reliably close to the simulated situation The measured data when it actually happened. The health state of the supporting cable in the model A _o is represented by the initial damage vector d _o of the evaluated object, and the steady-state temperature data of the cable structure is represented by the initial cable structure steady-state temperature data vector T _o . Since the calculated values of all monitored quantities calculated based on A _o are very close to the initial values of all monitored quantities (obtained by actual measurement), it can also be used on the basis of A _o to perform mechanical calculations, and each monitored quantity of A _o The calculated numerical value of the monitored quantity constitutes the initial numerical vector C _o of the monitored quantity. The "cable structure steady-state temperature data" corresponding to A _o is the "initial cable structure steady-state temperature data vector T _o "; the health state of the evaluated object corresponding to A _o is represented by the initial damage vector d _o of the evaluated object; The initial values of all the monitored quantities of A _o are represented by the initial value vector C _o of the monitored quantities. T _o and d _o are parameters of A _o , and C _o is composed of mechanical calculation results of A _o .

Step 3: Establish the current initial mechanical calculation benchmark model A ^t _o , the current initial value vector C ^t _o of the monitored quantity, and the "current initial cable structure steady-state temperature data vector T ^t _o " for the first time. The specific method is: at the initial Time, that is, when the current initial mechanical calculation benchmark model A ^t _o and the current initial value vector C ^t _o of the monitored quantity are established for the first time, A ^t _o is equal to A _o , C ^t _o is equal to C _o , and A ^t _o corresponds to "Cable structure steady-state temperature data" is recorded as "the current initial cable structure steady-state temperature data vector T ^t _o ", at the initial moment (that is, when A ^t _o is established for the first time), T ^t _o is equal to T _o , and the vector T ^t _o is defined in the same way as vector T _o . The health state of the evaluation object of A ^t _o is the same as the health state of the evaluation object of A _o (represented by the initial damage vector d _o of the evaluation object), and the health state of the evaluation object of A ^t _o is always initialized with the evaluation object The damage vector d _o represents. T ^t _o and do are parameters of A ^t _o , and C ^t _o is _composed of mechanical calculation results of A ^t _o .

Step 4: During the service process of the cable structure, the current data of the "steady-state temperature data of the cable structure" (called "current steady-state temperature data of the cable structure") are continuously measured and calculated according to "the temperature measurement and calculation method of the cable structure of this method". vector T ^t ”, the vector T ^t is defined in the same way as the vector T _o ). At the same time when the current steady-state temperature data vector T ^t of the cable structure is obtained by actual measurement, that is, at the same moment when the current steady-state temperature data vector T ^t of the cable structure is obtained, the current measured values of all monitored quantities of the cable structure are obtained by actual measurement, Form "the current value vector C of the monitored quantity". While obtaining the steady-state temperature data vector T ^t of the current cable structure, conduct non-destructive testing on the newly added M ₂ sensing cables, such as ultrasonic flaw detection, visual inspection, and infrared imaging inspection, to identify damaged or loose ones. Sensing cable, according to the numbering rule of the monitored quantity, removes the elements corresponding to the identified damaged or loose sensory cable from the vectors numbered according to the numbering rule of the monitored quantity that appear before this method, and appear after this method The elements corresponding to the identified damaged or loose sensor cables no longer appear in the vectors and matrices of , and when referring to the sensor cables after this method, the sensor cables that are identified as damaged or loose here are no longer included. cable, when referring to the monitored quantity after this method, no longer include the cable force of the sensor cable that is identified as being damaged or loose; _M2 and M are reduced by the same amount.

Step 5: According to the current cable structure steady-state temperature data vector T ^t , if necessary, update the current initial mechanical calculation benchmark model A ^t _o , the current initial value vector C ^t _o of the monitored quantity, and the current initial cable structure steady-state temperature data vector T ^t _o . After the current steady-state temperature data vector T ^t of the cable structure is measured in the fourth step, compare T ^t and T ^t _o , if T ^t is equal to T ^t _o , there is no need to update A ^t _o and T ^t _o , otherwise it is necessary To update A ^t _o and T ^t _o , the update method is as follows from step a to step c:

The first step is to calculate the difference between T ^t and T _o , the difference between T ^t and T _o is the change of the current steady-state temperature data of the cable structure with respect to the initial cable structure steady-state temperature data, and the difference between T ^t and T _o is the steady-state temperature change The vector S indicates that S is equal to T ^t minus T _o , and S indicates the change of the steady-state temperature data of the cable structure.

In step b, temperature changes are applied to the cable structure in A _o , and the value of the applied temperature change is taken from the steady _{-state temperature change vector S, and the support generalized displacement constraint is imposed on the cable structure support in A o and} the The current initial mechanical calculation benchmark model A ^t _o is updated after the temperature change imposed by the cable structure.

While A ^t _o is being updated in step c, all element values of T ^t _o are also replaced by corresponding values of all elements of T ^t , that is, T ^t _o is updated, so that T ^t _o corresponding to A ^t _o is obtained correctly; The method of updating C ^t _o is: after updating A ^t _o , the current specific values of all monitored quantities in A ^t _o are obtained through mechanical calculation, and these specific values form C ^t _o .

Step 6: Carry out several mechanical calculations on the basis of the current initial mechanical calculation benchmark model A ^t _o , and obtain the unit change matrix ΔC of the unit damage of the cable structure and the unit damage or unit generalized displacement vector C _u through calculation. The specific method is as follows: the cable structure unit damage unit change matrix ΔC is constantly updated, that is, the cable structure unit damage unit change matrix ΔC must be updated at the same time as the current initial mechanical calculation benchmark model A ^t _o is updated; Several mechanical calculations are performed on the basis of the current initial _mechanical calculation ^benchmark model A to of the cable structure. The number of calculations is numerically equal to the number of all evaluated objects. There are N evaluated objects and there are N calculations. Each calculation assumes Only one evaluated object has unit damage or unit generalized displacement. Specifically, if the evaluated object is a supporting cable in the cable system, then it is assumed that the supporting cable has been damaged in the vector d _o On the basis of unit damage (such as taking 5%, 10%, 20% or 30% damage as unit damage), if the evaluated object is a generalized displacement component of a support in one direction, it is assumed that the support is at The displacement direction is unit generalized displacement based on the existing generalized displacement of the support represented by vector d _o (for example, if the evaluated object is the linear displacement component of a support in the x direction, it is assumed that the support is at x There is a unit linear displacement in the direction, if the evaluated object is the angular displacement component of a support around the x-axis, it is assumed that the support has a unit angular displacement around the x-axis), use D _uk to record this unit damage or unit generalized displacement , where k represents the number of the evaluated object with unit damage or unit generalized displacement; the evaluated object with unit damage or unit generalized displacement in each calculation is different from the evaluated object with unit damage or unit generalized displacement in other calculations , each calculation uses the mechanical method to calculate the current calculation values of all the monitored quantities of the cable structure, and the current calculation values of all the monitored quantities obtained by each calculation form a monitored quantity calculation current vector C, and the monitored quantity calculates the current vector The element numbering rule of the element numbering rule is the same as the element numbering rule of the initial value vector C _o of the monitored quantity; the calculated current vector C of the monitored quantity obtained by each calculation is subtracted from the current initial value vector C ^t _o of the monitored quantity, and then divided by this calculation Assumed unit damage or unit generalized displacement value, a monitored quantity unit change vector is obtained. There are N monitored quantity unit change vectors if there are N evaluated objects; the N monitored quantity unit change vectors are composed in turn. The unit change matrix ΔC of unit damage monitored quantity with N columns; each column of the unit change matrix of unit damage monitored quantity corresponds to a monitored quantity unit change vector, and each row of the cable structure unit damage monitored quantity unit change matrix ΔC corresponds to Different unit change ranges of the same monitored quantity when unit damage or unit generalized displacement occurs in different evaluated objects; the numbering rules of the column of the cable structure unit damage monitored quantity unit change matrix ΔC and the numbering rules of the elements of the vector d _o Similarly, the row numbering rules of the cable structure unit damage monitored quantity unit change matrix ΔC are the same as the numbering rules of the M monitored quantities.

Step 7: Establish linear relationship error vector e and vector g. Using the previous data (the current initial value vector C ^t _o of the monitored quantity, and the unit change matrix ΔC of the monitored quantity for unit damage), each calculation is performed in the sixth step, that is, each calculation assumes that there is only one The increased unit damage or unit generalized displacement D _uk of the evaluated object, the evaluated object with increased unit damage or unit generalized displacement in each calculation is different from the evaluated object with increased unit damage or unit generalized displacement in other calculations, each calculation Both use mechanical methods (such as the finite element method) to calculate the current values of all monitored quantities in the cable structure. Each calculation forms a monitored quantity. When calculating the current vector C, each calculation forms a damage vector d. This step appears The damage vector d of the damage vector d is only used in this step. Among all the elements of the damage vector d, the value of only one element is D _uk , and the value of the other elements is 0. The numbering rules of the elements of the damage vector d are the same as the numbering rules of the elements of the vector d ₀ Same; put C, C _o , ΔC, _Du , and d into formula (12) to get a linear relationship error vector e, and get a linear relationship error vector e for each calculation; if there are N evaluated objects, there will be N times Calculate, there are N linear relationship error vectors e, add these N linear relationship error vectors e to get a vector, divide each element of this vector by N, and the new vector obtained is the final linear relationship error vector e. The vector g is equal to the final error vector e.

Step 8: Install the hardware part of the cable structure health monitoring system. The hardware part includes at least: monitored quantity monitoring system (such as cable force measurement system, signal conditioner, etc.), cable structure temperature monitoring system (including temperature sensor, signal conditioner, etc.) and cable structure environment temperature measurement system (including temperature sensor , signal conditioner, etc.), signal (data) collector, computer and communication alarm equipment. Every monitored quantity and every temperature must be monitored by the monitoring system. The monitoring system transmits the monitored signal to the signal (data) collector; the signal is transmitted to the computer through the signal collector; the computer is responsible for running the cable structure. The health monitoring software of the evaluation object includes recording the signal transmitted by the signal collector; when the health status of the evaluation object is monitored, the computer controls the communication alarm device to alarm the monitoring personnel, the owner and (or) the designated personnel.

Step 9: Save the current initial value vector C ^t _o of the monitored quantity, the unit change matrix ΔC of the monitored quantity for unit damage, and the unit damage or unit generalized displacement vector D _u parameters as data files in the computer running the health monitoring system software on the hard drive.

Step 10: Compile and install the system software of the generalized displacement identification method of damaged cables and supports for temperature change cable force monitoring on the computer. This software will complete the method "damaged cables and support generalized The monitoring, recording, control, storage, calculation, notification, alarm and other functions required by the task of "displacement recognition method" (that is, all the work that can be done by computer in this specific implementation method)

Step 11: According to the current value vector C of the monitored quantity, the current initial value vector C ^t _o of the monitored quantity, the unit change matrix ΔC of the monitored quantity for unit damage, the unit damage or unit generalized displacement vector D _u and the current nominal value of the evaluated object The approximate linear relationship (formula (8)) exists between the damage vector d (consisting of the current nominal damage of all cables), and the non-inferior solution of the current nominal damage vector d of the evaluated object is calculated according to the multi-objective optimization algorithm, that is, with reasonable error, but can determine the position of the damaged cable and the solution of the nominal damage degree from all the cables more accurately.

There are many kinds of multi-objective optimization algorithms that can be used, such as: multi-objective optimization based on genetic algorithm, multi-objective optimization based on artificial neural network, multi-objective optimization algorithm based on particle swarm, multi-objective optimization based on ant colony algorithm, constraint method (Constrain Method), Weighted Sum Method, Goal Attainment Method, etc. Since various multi-objective optimization algorithms are conventional algorithms, they can be implemented conveniently. This implementation step only uses the objective programming method as an example to give the process of solving the current damage vector d. The specific implementation process of other algorithms can be based on the requirements of their specific algorithms implemented in a similar manner.

According to the goal programming method, formula (8) can be transformed into the multi-objective optimization problem shown in formula (16) and formula (17). In formula (16), γ is a real number, R is a real number field, and the space region Ω limits the vector The value range of each element of d (this embodiment requires that each element of vector d is not less than 0 and not greater than 1). Equation (16) means to find a minimum real number γ, so that Equation (17) is satisfied. G(d) in formula (17) is defined by formula (18), the product of weighted vector W and γ in formula (17) represents the allowable deviation between G(d) and vector g in formula (17), the definition of g See formula (13), its value has been calculated in the seventh step. The vector W may be the same as the vector g during actual calculation. The specific programming implementation of the goal programming method already has a general program that can be directly adopted. The current nominal damage vector d of the evaluated object can be obtained by using the goal programming method.

$\begin{array}{cc}\mathrm{<span\; class="notranslate">\; min</span>}\mathrm{<span\; class="notranslate">\; imize</span>}& \mathrm{<span\; class="notranslate">\; \&gamma;</span>}\\ \mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; ,</span>& \mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; \&Element;</span>\mathrm{<span\; class="notranslate">\; \&Omega;</span>}\end{array}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 16</span>}<span\; class="notranslate">\; )</span>$

G(d)-Wγ≤g (17)

$\mathrm{<span\; class="notranslate">\; G</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; abs</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Delta;C</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; C</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 18</span>}<span\; class="notranslate">\; )</span>$

The number of elements of the current nominal damage vector d of the evaluated object is equal to the number of evaluated objects. There is a one-to-one correspondence between the elements of the current nominal damage vector d of the evaluated object and the evaluated object. The current nominal damage vector d of the evaluated object The value of the element represents the nominal damage degree or the nominal generalized displacement of the corresponding evaluated object; the numbering rule of the elements of the vector d is the same as that of the elements of the vector d _o .

Step 12: Define the current actual damage vector d ^a of the evaluated object, the number of elements of the current actual damage vector d ^a of the evaluated object is equal to the number of evaluated objects, the elements of the current actual damage vector d ^a of the evaluated object There is a one-to-one correspondence between the objects, and the element value of the current actual damage vector d ^a of the evaluated object represents the actual damage degree or actual generalized displacement of the corresponding evaluated object; the numbering rules of the elements of the vector d ^a are the same as those of the elements of the vector d _o The numbering rules are the same. The kth element d ^a _k of the current actual damage vector d ^a of the evaluated object expressed by formula (15) is the same as the kth element d _ok of the initial damage vector d _o of the evaluated object and the current nominal damage vector d of the evaluated object The relationship between the kth element d _k is calculated to obtain all the elements of the current actual damage vector d ^a of the evaluated object; d ^a _k represents the current actual health status of the kth evaluated object, if the evaluated object is in the cable system , then d ^a _k represents its current actual damage. When d ^a _k is 0, it means no damage. When it is 100%, it means that the supporting cable completely loses its bearing capacity. When it is between 0 and 100%, it means that it is lost The bearing capacity of the corresponding proportion, if the evaluated object is a generalized displacement component of a support, then d ^a _k represents its current actual generalized displacement value; so according to the current actual damage vector d ^a of the evaluated object, it can be determined which supporting cables The damage and its damage degree are determined, which supports have undergone generalized displacement and their values, that is, the identification of the damaged cable and support generalized displacement of the cable structure is realized.

Step 13: The computer in the health monitoring system generates reports on the health status of the cable system automatically or by personnel operating the health monitoring system on a regular basis.

Step 14: Under the specified conditions, the computer in the health monitoring system automatically operates the communication alarm equipment to alarm the monitoring personnel, the owner and (or) the designated personnel.

Step 15: Go back to step 4 and start the cycle from step 4 to step 15.

Claims (1)

1. the damaged cable of temperature variation cable force monitoring and a generalized displacement of support recognition methods, is characterized in that described method comprises:

A. for sake of convenience, this method unitedly calls evaluated support cable and generalized displacement of support component to be evaluation object, if the quantity sum of the quantity of evaluated support cable and generalized displacement of support component is N, namely the quantity of evaluation object is N; Determine the coding rule of evaluation object, evaluation objects all in Cable Structure numbered by this rule, this numbering will be used for generating vector sum matrix in subsequent step; This method variable k represents this numbering, k=1,2,3 ..., N; If total M in cable system ₁root support cable, Cable Structure rope force data comprises this M ₁the Suo Li of root support cable, obvious M ₁be less than the quantity N of evaluation object; Only by M ₁the M of individual support cable ₁the state that individual rope force data solves unknown N number of evaluation object is impossible, and this method is at the whole M of monitoring ₁on the basis of root supporting cable force, Cable Structure artificially increases M ₂root rope, is called sensing rope, by this M newly increased of monitoring in cable structure health monitoring process ₂the Suo Li of root sensing rope; Comprehensive above-mentioned monitored amount, M the Suo Li that whole Cable Structure has M root rope is monitored, and namely have M monitored amount, wherein M is M ₁with M ₂sum; M should be greater than the quantity N of evaluation object; The M newly increased ₂the rigidity of root sensing rope is compared with the rigidity of any support cable of Cable Structure, should be much smaller; The M newly increased ₂the Suo Li of each sensing rope of root sensing rope should be more much smaller than the Suo Li of any support cable of Cable Structure, even if can ensure this M newly increased like this ₂root sensing rope has occurred damaging or lax, very little on the impact of the stress of other components of Cable Structure, strain, distortion; The M newly increased ₂on the xsect of root sensing rope, normal stress should be less than its fatigue limit, and these require the M ensureing to newly increase ₂can not fatigue damage be there is in root sensing rope; The M newly increased ₂the two ends of root sensing rope should fully anchoring, ensures to there will not be lax; The M newly increased ₂root sensing rope should obtain sufficient anti-corrosion protection, ensures the M newly increased ₂damage can not be there is and relax in root sensing rope; For simplicity, in the method by " monitored all parameters of Cable Structure " referred to as " monitored amount "; To M monitored amount serial number, this method variable j represents this numbering, j=1,2,3 ..., M, this numbering will be used for generating vector sum matrix in subsequent step; The M newly increased in the method ₂root sensing rope is as a part for Cable Structure, and when hereinafter mentioning Cable Structure again, Cable Structure comprises increases M ₂cable Structure before root sensing rope and the M newly increased ₂root sensing rope, refers to comprise the M newly increased when that is hereinafter mentioning Cable Structure ₂the Cable Structure of root sensing rope; Therefore hereinafter mention when obtaining " Cable Structure steady temperature data " according to " the temperature survey calculating method of the Cable Structure of this method " survey calculation, Cable Structure wherein comprises the M newly increased ₂root sensing rope, " the Cable Structure steady temperature data " that obtain comprise the M newly increased ₂the steady temperature data of root sensing rope, obtain the M newly increased ₂the method of the steady temperature data of root sensing rope is same as the M of Cable Structure ₁the preparation method of the steady temperature data of root support cable, hands over later no longer one by one; Measure the M obtaining newly increasing ₂the method of the Suo Li of root sensing rope is same as the M of Cable Structure ₁the measuring method of the Suo Li of root support cable, hands over later no longer one by one; When carrying out any measurement to the support cable of Cable Structure, simultaneously to the M newly increased ₂root sensing rope carries out same measurement, hands over no longer one by one later; The M newly increased ₂root sensing rope except there is not damage and be lax, to the M newly increased ₂the requirement of the quantity of information of root sensing rope is identical with preparation method with the requirement of the quantity of information of the support cable of Cable Structure with preparation method, hands over no longer one by one later; When setting up the various mechanical model of Cable Structure later, by the M newly increased ₂the support cable that Cable Structure treated as by root sensing rope is treated; Below, except the damage of mentioning support cable and lax occasion, the support cable that said support cable comprises Cable Structure when mentioning support cable and the M newly increased ₂root sensing rope; Must not be greater than 30 minutes to the time interval between any twice measurement of same amount Real-Time Monitoring in this method, the moment of survey record data is called the physical record data moment;

B. this method definition " the temperature survey calculating method of the Cable Structure of this method " is undertaken by step b1 to b3;

B1: inquiry or actual measurement obtain the temperature variant thermal conduction study parameter of environment residing for Cable Structure composition material and Cable Structure, utilize the geometry measured data of the design drawing of Cable Structure, as-constructed drawing and Cable Structure, utilize these data and parameter to set up the Thermodynamic calculation model of Cable Structure, inquiry Cable Structure location is no less than the meteorological data in recent years of 2 years, the statistics cloudy quantity obtained is during this period of time designated as T cloudy day, in the method daytime can not be seen one of the sun and be called the cloudy day all day, statistics obtains 0 highest temperature after sunrise moment next day between 30 minutes and the lowest temperature at each cloudy day in T cloudy day, the sunrise moment refers to the sunrise moment on the meteorology that base area revolutions and revolution rule are determined, do not represent that the same day one sees the sun surely, inquiry data or calculated sunrise moment of each required day by conventional meteorology, 0 highest temperature after sunrise moment next day between 30 minutes at each cloudy day deducts the maximum temperature difference that the lowest temperature is called the daily temperature at this cloudy day, there is T cloudy day, just there is the maximum temperature difference of the daily temperature at T cloudy day, the maximal value of getting in the maximum temperature difference of the daily temperature at T cloudy day is reference temperature difference per day, Δ T is designated as with reference to temperature difference per day _r, be no less than between inquiry Cable Structure location and Altitude Region, place temperature that the meteorological data in recent years of 2 years or actual measurement obtain environment residing for Cable Structure in time with delta data and the Changing Pattern of sea level elevation, calculate to be no less than 2 years between Cable Structure location and Altitude Region, place Cable Structure in recent years residing for the temperature of environment about the maximum rate of change Δ T of sea level elevation _h, get Δ T for convenience of describing _hunit be DEG C/m, the surface of Cable Structure is got " R Cable Structure surface point ", the Specific Principles getting " R Cable Structure surface point " describes in step b3, the temperature of this R Cable Structure surface point will be obtained below by actual measurement, claiming to survey the temperature data obtained is " R Cable Structure surface temperature measured data ", if utilize the Thermodynamic calculation model of Cable Structure, obtained the temperature of this R Cable Structure surface point by Calculation of Heat Transfer, just claim the temperature data that calculates for " R Cable Structure land surface pyrometer count certificate ", from the minimum height above sea level residing for Cable Structure to most High aititude, in Cable Structure, uniform choosing is no less than three different sea level elevations, at the sea level elevation place that each is chosen, two points are at least chosen at the intersection place on surface level and Cable Structure surface, from the outer normal of selected point straw line body structure surface, all outer normal directions chosen are called " measuring the direction of Cable Structure along the Temperature Distribution of wall thickness ", measure Cable Structure crossing with " intersection on surface level and Cable Structure surface " along the direction of the Temperature Distribution of wall thickness, in in the shade the outer normal direction of the measurement Cable Structure chosen along the sunny slope outer normal direction and Cable Structure that must comprise Cable Structure in the direction of the Temperature Distribution of wall thickness, three points are no less than along each measurement Cable Structure along direction uniform choosing in Cable Structure of the Temperature Distribution of wall thickness, along each, Cable Structure is measured for support cable and only gets a point along the direction of the Temperature Distribution of wall thickness, only measure the temperature of the surface point of support cable, measure all temperature be selected a little, the temperature recorded is called " Cable Structure is along the temperature profile data of thickness ", wherein along crossing with same " intersection on surface level and Cable Structure surface ", " measure the direction of Cable Structure along the Temperature Distribution of wall thickness " to measure " Cable Structure is along the temperature profile data of thickness " that obtain, be called in the method " identical sea level elevation Cable Structure is along the temperature profile data of thickness ", if have chosen the individual different sea level elevation of H, at each sea level elevation place, have chosen B and measure the direction of Cable Structure along the Temperature Distribution of wall thickness, in Cable Structure, E point is have chosen along each measurement Cable Structure along the direction of the Temperature Distribution of wall thickness, wherein H and E is not less than 3, B is not less than 2, 1 is equaled for support cable E, the sum that Cable Structure " measures the point of Cable Structure along the temperature profile data of thickness " represents with symbol HBE, the temperature of this HBE " measuring the point of Cable Structure along the temperature profile data of thickness " will be obtained below by actual measurement, claiming to survey the temperature data obtained is " HBE Cable Structure is along thickness temperature measured data ", if utilize the Thermodynamic calculation model of Cable Structure, obtain this HBE by Calculation of Heat Transfer and measure the temperature of Cable Structure along the point of the temperature profile data of thickness, the temperature data calculated just is claimed to be " HBE Cable Structure calculates data along thickness temperature ", measure temperature in Cable Structure location according to meteorology to require to choose a position, obtain meeting the temperature that meteorology measures the Cable Structure place environment of temperature requirement by the actual measurement of this position, in the on-site spaciousness of Cable Structure, unobstructed place chooses a position, this position should each of the whole year day can obtain this ground the most sufficient sunshine of this day getable, at the flat board of this position of sound production one piece of carbon steel material, be called reference plate, reference plate can not contact with ground, reference plate overhead distance is not less than 1.5 meters, the one side of this reference plate on the sunny side, be called sunny slope, the sunny slope of reference plate is coarse with dark color, the sunny slope of reference plate should each of the whole year day can obtain one flat plate on this ground the most sufficient sunshine of this day getable, the non-sunny slope of reference plate is covered with insulation material, Real-Time Monitoring is obtained the temperature of the sunny slope of reference plate,

B2: Real-Time Monitoring obtains R Cable Structure surface temperature measured data of above-mentioned R Cable Structure surface point, Real-Time Monitoring obtains the temperature profile data of previously defined Cable Structure along thickness simultaneously, and Real-Time Monitoring obtains meeting the temperature record that meteorology measures the Cable Structure place environment of temperature requirement simultaneously, the temperature measured data sequence of the Cable Structure place environment after sunrise moment next day between 30 minutes is obtained being carved at sunrise the same day by Real-Time Monitoring, the temperature measured data sequence of Cable Structure place environment is arranged according to time order and function order by the temperature measured data of the Cable Structure place environment after being carved into the sunrise moment next day same day at sunrise between 30 minutes, find the maximum temperature in the temperature measured data sequence of Cable Structure place environment and minimum temperature, the maximum temperature difference be carved at sunrise on same day that minimum temperature obtains Cable Structure place environment after sunrise moment next day between 30 minutes is deducted by the maximum temperature in the temperature measured data sequence of Cable Structure place environment, be called environment maximum temperature difference, be designated as Δ T _emax, calculated the rate of change of temperature about the time of Cable Structure place environment by Conventional mathematical by the temperature measured data sequence of Cable Structure place environment, this rate of change is also along with time variations, the measured data sequence of the temperature of the sunny slope of the reference plate after sunrise moment next day between 30 minutes is obtained being carved at sunrise the same day by Real-Time Monitoring, the measured data sequence of the temperature of the sunny slope of reference plate is arranged according to time order and function order by the measured data of the temperature of the sunny slope of the reference plate after being carved into the sunrise moment next day same day at sunrise between 30 minutes, find the maximum temperature in the measured data sequence of the temperature of the sunny slope of reference plate and minimum temperature, the maximum temperature difference be carved at sunrise on same day that minimum temperature obtains the temperature of the sunny slope of reference plate after sunrise moment next day between 30 minutes is deducted by the maximum temperature in the measured data sequence of the temperature of the sunny slope of reference plate, be called reference plate maximum temperature difference, be designated as Δ T _pmax, the Cable Structure surface temperature measured data sequence of all R Cable Structure surface points after sunrise moment next day between 30 minutes is obtained being carved at sunrise the same day by Real-Time Monitoring, R Cable Structure surface point is had just to have R Cable Structure surface temperature measured data sequence, each Cable Structure surface temperature measured data sequence is arranged according to time order and function order by the Cable Structure surface temperature measured data after being carved into the sunrise moment next day same day of a Cable Structure surface point at sunrise between 30 minutes, find the maximum temperature in each Cable Structure surface temperature measured data sequence and minimum temperature, the maximum temperature difference be carved at sunrise on same day that minimum temperature obtains the temperature of each Cable Structure surface point after sunrise moment next day between 30 minutes is deducted by the maximum temperature in each Cable Structure surface temperature measured data sequence, there is R Cable Structure surface point just to have to be carved at sunrise R the same day maximum temperature difference numerical value between 30 minutes after sunrise moment next day, maximal value is wherein called Cable Structure surface maximum temperature difference, be designated as Δ T _smax, calculated the rate of change of temperature about the time of each Cable Structure surface point by Conventional mathematical by each Cable Structure surface temperature measured data sequence, the temperature of each Cable Structure surface point about the rate of change of time also along with time variations, obtain being carved at sunrise the same day after sunrise moment next day between 30 minutes by Real-Time Monitoring, at synchronization, after HBE " Cable Structure is along the temperature profile data of thickness ", calculate the difference amounting to maximum temperature in BE " identical sea level elevation Cable Structure is along the temperature profile data of thickness " and minimum temperature at the sea level elevation place that each is chosen, the absolute value of this difference is called " identical sea level elevation place Cable Structure thickness direction maximum temperature difference ", have chosen H different sea level elevation just to have H " identical sea level elevation place Cable Structure thickness direction maximum temperature difference ", the maximal value in this H " identical sea level elevation place Cable Structure thickness direction maximum temperature difference " is claimed to be " Cable Structure thickness direction maximum temperature difference ", be designated as Δ T _tmax,

B3: survey calculation obtains Cable Structure steady temperature data, first, determine the moment obtaining Cable Structure steady temperature data, the condition relevant to the moment determining to obtain Cable Structure steady temperature data has six, Section 1 condition is moment of obtaining Cable Structure steady temperature data between after being carved into sunrise moment next day at sunset between 30 minutes on same day, the sunset moment refers to the sunset moment on base area revolutions and the meteorology determined of revolution rule, inquiry data or calculated sunset moment of each required day by conventional meteorology, the a condition of Section 2 condition be after being carved into sunrise moment next day at sunrise between 30 minutes on same day during this period of time in, reference plate maximum temperature difference Δ T _pmaxwith Cable Structure surface maximum temperature difference Δ T _smaxall be not more than 5 degrees Celsius, the b condition of Section 2 condition be after being carved into sunrise moment next day at sunrise between 30 minutes on same day during this period of time in, the environment maximum temperature difference Δ T that survey calculation obtains above _emaxbe not more than with reference to temperature difference per day Δ T _r, and reference plate maximum temperature difference Δ T _pmaxΔ T is not more than after deducting 2 degrees Celsius _emax, and Cable Structure surface maximum temperature difference Δ T _smaxbe not more than Δ T _pmax, one of only need meet in a condition of Section 2 and b condition is just called and meets Section 2 condition, Section 3 condition is when obtaining Cable Structure steady temperature data, and the temperature of Cable Structure place environment is not more than 0.1 degree Celsius per hour about the absolute value of the rate of change of time, Section 4 condition is when obtaining Cable Structure steady temperature data, and the temperature of each the Cable Structure surface point in R Cable Structure surface point is not more than 0.1 degree Celsius per hour about the absolute value of the rate of change of time, Section 5 condition is when obtaining Cable Structure steady temperature data, and the Cable Structure surface temperature measured data of each the Cable Structure surface point in R Cable Structure surface point is be carved into the minimal value after sunrise moment next day between 30 minutes the same day at sunrise, Section 6 condition is when obtaining Cable Structure steady temperature data, " Cable Structure thickness direction maximum temperature difference " Δ T _tmaxbe not more than 1 degree Celsius, this method utilizes above-mentioned six conditions, any one in following three kinds of moment is called " the mathematics moment obtaining Cable Structure steady temperature data ", simultaneously the first moment meets the moment of the Section 1 in above-mentioned " condition relevant to the moment determining to obtain Cable Structure steady temperature data " to Section 5 condition, the second moment is moment of the Section 6 condition only met in above-mentioned " condition relevant to determining to obtain moment of Cable Structure steady temperature data ", simultaneously the third moment meets the moment of the Section 1 in above-mentioned " condition relevant to the moment determining to obtain Cable Structure steady temperature data " to Section 6 condition, when the mathematics moment obtaining Cable Structure steady temperature data is exactly one in this method in the physical record data moment, the moment obtaining Cable Structure steady temperature data is exactly the mathematics moment obtaining Cable Structure steady temperature data, if the mathematics moment obtaining Cable Structure steady temperature data is not any one moment in this method in the physical record data moment, then getting this method closest to moment of those physical record data in the mathematics moment obtaining Cable Structure steady temperature data is the moment obtaining Cable Structure steady temperature data, the amount being used in the moment survey record obtaining Cable Structure steady temperature data is carried out Cable Structure relevant health monitoring analysis by this method, this method thinks that the Cable Structure temperature field in the moment obtaining Cable Structure steady temperature data is in stable state, and namely the Cable Structure temperature in this moment does not change in time, and this moment is exactly " obtaining the moment of Cable Structure steady temperature data " of this method, then, according to Cable Structure heat transfer characteristic, utilize " R the Cable Structure surface temperature measured data " and " HBE Cable Structure is along thickness temperature measured data " in the moment obtaining Cable Structure steady temperature data, utilize the Thermodynamic calculation model of Cable Structure, the Temperature Distribution of the Cable Structure in the moment obtaining Cable Structure steady temperature data is calculated by conventional heat transfer, now the temperature field of Cable Structure calculates by stable state, the temperature profile data of the Cable Structure in the moment in acquisition Cable Structure steady temperature data calculated comprises the accounting temperature of R Cable Structure surface point in Cable Structure, the accounting temperature of R Cable Structure surface point is called that R Cable Structure steady-state surface temperature calculates data, also comprise the accounting temperature of Cable Structure selected HBE " measuring the point of Cable Structure along the temperature profile data of thickness " above, the accounting temperature of HBE " measuring the point of Cable Structure along the temperature profile data of thickness " is called " HBE Cable Structure calculates data along thickness temperature ", when R Cable Structure surface temperature measured data and R Cable Structure steady-state surface temperature calculate data correspondent equal, and when " HBE Cable Structure is along thickness temperature measured data " and " HBE Cable Structure calculates data along thickness temperature " correspondent equal, the temperature profile data of the Cable Structure in the moment in acquisition Cable Structure steady temperature data calculated is called " Cable Structure steady temperature data " in the method, " R Cable Structure surface temperature measured data " is now called " R Cable Structure steady-state surface temperature measured data ", " HBE Cable Structure is along thickness temperature measured data " is called " HBE Cable Structure is along thickness steady temperature measured data ", when the surface of Cable Structure is got " R Cable Structure surface point ", the quantity of " R Cable Structure surface point " must meet three conditions with distribution, first condition is when Cable Structure temperature field is in stable state, when the temperature of Cable Structure any point be on the surface by " R Cable Structure surface point " in obtain with the observed temperature linear interpolation of the Cable Structure point that this arbitrfary point is adjacent on the surface time, the error of the Cable Structure that linear interpolation the obtains temperature of this arbitrfary point and the Cable Structure actual temperature of this arbitrfary point on the surface is on the surface not more than 5%, Cable Structure surface comprises support cable surface, second condition is not less than 4 in the quantity of the point of same sea level elevation in " R Cable Structure surface point ", and uniform along Cable Structure surface at the point of same sea level elevation in " R Cable Structure surface point ", " R Cable Structure surface point " is not more than 0.2 DEG C divided by Δ T along the maximal value Δ h in the absolute value of all differences of the sea level elevation of adjacent Cable Structure surface point between two of sea level elevation _hthe numerical value obtained, gets Δ T for convenience of describing _hunit be DEG C/m, be m for convenience of describing the unit getting Δ h, " R Cable Structure surface point " along the definition of the adjacent between two Cable Structure surface point of sea level elevation refer to only consider sea level elevation time, in " R Cable Structure surface point ", there is not a Cable Structure surface point, the sea level elevation numerical value of this Cable Structure surface point is between the sea level elevation numerical value of adjacent Cable Structure surface point between two, 3rd condition is inquiry or obtains the rule at sunshine between Cable Structure location and Altitude Region, place by meteorology conventionally calculation, again according to geometric properties and the bearing data of Cable Structure, Cable Structure finds the annual position by sunshine-duration those surface points the most sufficient, in " R Cable Structure surface point ", has at least a Cable Structure surface point to be annual by a point in sunshine-duration the most fully those surface points in Cable Structure,

C. the Cable Structure steady temperature data under original state are obtained according to " the temperature survey calculating method of the Cable Structure of this method " direct survey calculation, Cable Structure steady temperature data under original state are called initial Cable Structure steady temperature data, are designated as " initial Cable Structure steady temperature data vector T _o"; Survey or consult reference materials and obtain the temperature variant physical and mechanical properties parameter of the various materials that Cable Structure uses; T is obtained in actual measurement _owhile, namely at the initial Cable Structure steady temperature data vector T of acquisition _othe synchronization in moment, direct survey calculation obtains the measured data of initial Cable Structure, and the measured data of initial Cable Structure comprises the Non-destructive Testing Data of the health status expressing support cable, Cable Structure bearing initial generalized displacement measurement data, the initial value of all monitored amounts, the Initial cable force data of all support cables, initial Cable Structure modal data, initial Cable Structure strain data, initial Cable Structure geometric data, initial Cable Structure bearing generalized coordinate data, initial Cable Structure angle-data, initial Cable Structure spatial data; The initial value of all monitored amounts forms monitored amount initial value vector C _o, monitored amount initial value vector C _othe coding rule of coding rule and M monitored amount identical; Utilization can express the Non-destructive Testing Data of the health status of support cable and the initial generalized displacement measurement data of Cable Structure bearing sets up evaluation object initial damage vector d _o, vectorial d _orepresent with initial mechanical Calculation Basis model A _othe initial health of the evaluation object of the Cable Structure represented; Evaluation object initial damage vector d _oelement number equal N, d _oelement and evaluation object be one-to-one relationship, vectorial d _othe coding rule of element identical with the coding rule of evaluation object; If d _oevaluation object corresponding to some elements be support cable, so a d in cable system _othe numerical value of this element represent the initial damage degree of corresponding support cable, if the numerical value of this element is 0, represent that the support cable corresponding to this element is intact, do not damage, if its numerical value is 100%, then represent that the support cable corresponding to this element completely loses load-bearing capacity, if its numerical value is between 0 and 100%, then represent that this support cable loses the load-bearing capacity of corresponding proportion; If d _oevaluation object corresponding to some elements be some generalized displacement components of some bearings, so d _othe numerical value of this element represent the initial value of this generalized displacement component of this bearing; If there is no the Non-destructive Testing Data of support cable and other are when can express the data of the health status of support cable, or think structure original state be not damaged without relaxed state time, vectorial d _oin each element numerical value relevant to support cable get 0, if when there is no Cable Structure bearing initial generalized displacement measurement data or think that the initial generalized displacement of Cable Structure bearing is 0, vectorial d _oin each element numerical value relevant to Cable Structure generalized displacement of support get 0; Initial Cable Structure bearing generalized coordinate data refer to the support coordinate data under Cable Structure design point, and Cable Structure bearing initial generalized displacement measurement data refers to setting up initial mechanical Calculation Basis model A _otime, the generalized displacement that Cable Structure bearing occurs relative to the bearing under Cable Structure design point; Bearing generalized coordinate comprises line amount and angular amount two kinds;

Temperature variant physical and mechanical properties parameter, the initial Cable Structure steady temperature data vector T of the various materials d. used according to the measured data of the design drawing of Cable Structure, as-constructed drawing and initial Cable Structure, the Non-destructive Testing Data of support cable, Cable Structure bearing initial generalized displacement measurement data, Cable Structure _owith all Cable Structure data that preceding step obtains, set up the initial mechanical Calculation Basis model A counting the Cable Structure of " Cable Structure steady temperature data " _o, based on A _othe Cable Structure that calculates calculates data must closely its measured data, and difference therebetween must not be greater than 5%; Corresponding to A _o" Cable Structure steady temperature data " be exactly " initial Cable Structure steady temperature data vector T _o"; Corresponding to A _oevaluation object health status with evaluation object initial damage vector d _orepresent; Corresponding to A _othe initial value monitored amount initial value vector C of all monitored amount _orepresent; First time sets up the current initial mechanical Calculation Basis model A counting the Cable Structure of " Cable Structure steady temperature data " ^t _o, monitored amount current initial value vector C ^t _o" current initial Cable Structure steady temperature data vector T ^t _o"; Set up the current initial mechanical Calculation Basis model A of Cable Structure for the first time ^t _owith monitored amount current initial value vector C ^t _otime, the current initial mechanical Calculation Basis model A of Cable Structure ^t _ojust equal the initial mechanical Calculation Basis model A of Cable Structure _o, monitored amount current initial value vector C ^t _ojust equal monitored amount initial value vector C _o; A ^t _ocorresponding " Cable Structure steady temperature data " are called " current initial Cable Structure steady temperature data ", are designated as " current initial Cable Structure steady temperature data vector T ^t _o", set up the current initial mechanical Calculation Basis model A of Cable Structure for the first time ^t _otime, T ^t _ojust equal T _o; A ^t _othe initial health of evaluation object and A _othe health status of evaluation object identical, also use evaluation object initial damage vector d _orepresent, A in cyclic process below ^t _othe initial health of evaluation object use evaluation object initial damage vector d all the time _orepresent; T _oand d _oa _oparameter, by A _othe initial value of all monitored amount that obtains of Mechanics Calculation result and C _othe initial value of all monitored amount represented is identical, therefore says C _oby A _omechanics Calculation result composition; T ^t _oand d _oa ^t _oparameter, C ^t _oby A ^t _omechanics Calculation result composition;

E. from entering the circulation being walked to m step by e here, in structure military service process, the current data of " Cable Structure steady temperature data " is constantly obtained according to " the temperature survey calculating method of the Cable Structure of this method " continuous Actual measurement, the current data of " Cable Structure steady temperature data " is called " current cable structure steady temperature data ", is designated as " current cable structure steady temperature data vector T ^t", vector T ^tdefinition mode and vector T _odefinition mode identical, current cable structure steady temperature data vector T is obtained in actual measurement ^twhile, to the M newly increased ₂root sensing rope carries out Non-Destructive Testing, therefrom identify and occur damage or lax sensing rope, according to monitored amount coding rule, the element that the sensing rope that to damage with the appearance identified or relax is corresponding is removed from each vector according to monitored amount coding rule numbering occurred before this method, also the element damaged with the appearance identified or lax sensing rope is corresponding is no longer there is in each vector sum matrix occurred after this method, no longer comprise when mentioning sensing rope after this method being identified here and occur damage or lax sensing rope, the Suo Li being identified and occurring damage or lax sensing rope is no longer comprised here when mentioning monitored amount after this method, identify several from Cable Structure and occur damage or lax sensing rope, just by M ₂same quantity is reduced with M,

F. according to current cable structure steady temperature data vector T ^t, upgrade current initial mechanical Calculation Basis model A according to step f1 to f3 ^t _o, monitored amount current initial value vector C ^t _owith current initial Cable Structure steady temperature data vector T ^t _o;

F1. T is compared ^twith T ^t _oif, T ^tequal T ^t _o, then A ^t _o, C ^t _oand T ^t _oremain unchanged; Otherwise need to follow these steps to A ^t _o, U ^t _o, C ^t _oand T ^t _oupgrade;

F2. T is calculated ^twith T _odifference, T ^twith T _odifference be exactly the changes of current cable structure steady temperature data about initial Cable Structure steady temperature data, T ^twith T _odifference represent with steady temperature change vector S, S equals T ^tdeduct T _o, S represents the change of Cable Structure steady temperature data;

F3. to A _oin Cable Structure apply temperature variation, the numerical value of the temperature variation of applying just takes from steady temperature change vector S, to A _oin Cable Structure apply temperature variation after obtain upgrade current initial mechanical Calculation Basis model A ^t _o, upgrade A ^t _owhile, T ^t _oall elements numerical value also uses T ^tall elements numerical value correspondence replace, namely have updated T ^t _o, so just obtain and correctly correspond to A ^t _ot ^t _o; Upgrade C ^t _omethod be: when renewal A ^t _oafter, obtain A by Mechanics Calculation ^t _oin all monitored amounts, current concrete numerical value, these concrete numerical value composition C ^t _o; A ^t _othe initial health of support cable use evaluation object initial damage vector d all the time _orepresent;

G. at current initial mechanical Calculation Basis model A ^t _obasis on carry out several times Mechanics Calculation according to step g 1 to g4, obtain Cable Structure unit damage monitored amount unit change matrix Δ C and unit damage or unit generalized displacement vector D by calculating _u;

G1. Cable Structure unit damage monitored amount unit change matrix Δ C constantly updates, namely at the current initial mechanical Calculation Basis model A of renewal ^t _o, monitored amount current initial value vector C ^t _owith current initial Cable Structure steady temperature data vector T ^t _oafterwards, the vectorial D of Cable Structure unit damage monitored amount unit change matrix Δ C and unit damage or unit generalized displacement must then be upgraded _u;

G2. at the current initial mechanical Calculation Basis model A of Cable Structure ^t _obasis on carry out several times Mechanics Calculation, calculation times numerically equals the quantity N of all evaluation objects, has N number of evaluation object just to have N calculating; According to the coding rule of evaluation object, calculate successively; Calculating hypothesis each time only has an evaluation object to increase unit damage or unit generalized displacement again on the basis of original damage or generalized displacement, if this evaluation object is a support cable in cable system, so just suppose that this support cable increases unit damage again, if this evaluation object is the generalized displacement component in a direction of a bearing, just suppose that this bearing increases unit generalized displacement again at this sense of displacement, use D _ukrecord unit damage or the unit generalized displacement of this increase, wherein k represents the numbering of the evaluation object increasing unit damage or unit generalized displacement, D _ukunit damage or unit generalized displacement vector D _uan element, unit damage or unit generalized displacement vector D _uthe coding rule of element and vectorial d _othe coding rule of element identical; The evaluation object increasing unit damage or unit generalized displacement in calculating each time is different from during other time calculates the evaluation object increasing unit damage or unit generalized displacement, calculate the current calculated value all utilizing mechanics method to calculate all monitored amount of Cable Structure each time, the current calculated value of all monitored amount calculated each time forms a monitored amount calculation current vector, element number rule and the monitored amount initial value vector C of monitored amount calculation current vector _oelement number rule identical;

G3. the monitored amount calculation current vector calculated each time deducts monitored amount current initial value vector C ^t _oobtain a vector, then each element of this vector is calculated the unit damage or unit generalized displacement numerical value supposed divided by this time, obtain a monitored amount unit change vector, have N number of evaluation object just to have N number of monitored amount unit change vector;

G4. by the vectorial coding rule according to N number of evaluation object of this N number of monitored amount unit change, the Cable Structure unit damage monitored amount unit change matrix Δ C having N to arrange is formed successively; Each row of Cable Structure unit damage monitored amount unit change matrix Δ C correspond to a monitored amount unit change vector; Every a line of Cable Structure unit damage monitored amount unit change matrix Δ C corresponds to the different unit change amplitude of same monitored amount when different evaluation object increases unit damage or unit generalized displacement; The coding rule of the row of Cable Structure unit damage monitored amount unit change matrix Δ C and vectorial d _othe coding rule of element identical, the coding rule of the row of Cable Structure unit damage monitored amount unit change matrix Δ C is identical with the coding rule of M monitored amount;

H. current cable structure steady temperature data vector T is obtained in actual measurement ^twhile, actual measurement obtains at acquisition current cable structure steady temperature data vector T ^tthe current measured value of all monitored amount of Cable Structure of synchronization in moment, form monitored amount current value vector C; Monitored amount current value vector C and monitored amount current initial value vector C ^t _owith monitored amount initial value vector C _odefinition mode identical, the same monitored amount of element representation of three vectorial identical numberings is at not concrete numerical value in the same time;

I. evaluation object current nominal fatigue vector d is defined, the element number of evaluation object current nominal fatigue vector d equals the quantity of evaluation object, be one-to-one relationship between the element of evaluation object current nominal fatigue vector d and evaluation object, the element numerical value of evaluation object current nominal fatigue vector d represents the nominal fatigue degree of corresponding evaluation object or nominal generalized displacement; The coding rule of the element of vector d and vectorial d _othe coding rule of element identical;

J. according to monitored amount current value vector C with monitored amount current initial value vector C ^t _o, Cable Structure unit damage monitored amount unit change matrix Δ C, unit damage or unit generalized displacement vector D _uand the linear approximate relationship existed between evaluation object to be asked current nominal fatigue vector d, this linear approximate relationship can be expressed as formula 1, and other amount in formula 1 except d is known, solves formula 1 and just can calculate evaluation object current nominal fatigue vector d;

$C=C_o^t+\mathrm{\&Delta;C}\&CenterDot;d$ Formula 1

K. evaluation object current actual damage vector d is defined ^a, evaluation object current actual damage vector d ^aelement number equal the quantity of evaluation object, evaluation object current actual damage vector d ^aelement and evaluation object between be one-to-one relationship, evaluation object current actual damage vector d ^aelement numerical value represent the actual damage degree of corresponding evaluation object or actual generalized displacement; Vector d ^athe coding rule of element and vectorial d _othe coding rule of element identical;

L. the evaluation object utilizing formula 2 to express current actual damage vector d ^aa kth element d ^a _kwith evaluation object initial damage vector d _oa kth element d _okwith a kth element d of evaluation object current nominal fatigue vector d _kbetween relation, calculate evaluation object current actual damage vector d ^aall elements;

K=1 in formula 2,2,3 ...., N, d ^a _krepresent the current actual health status of a kth evaluation object, if this evaluation object is support cable, so a d in cable system ^a _krepresent its current actual damage, d ^a _krepresent not damaged when being 0, when being 100%, represent that this support cable thoroughly loses load-bearing capacity, represent the load-bearing capacity losing corresponding proportion time between 0 and 100%, if this evaluation object is generalized displacement component, so a d of a bearing ^a _krepresent its current actual generalized displacement numerical value; So according to evaluation object current actual damage vector d ^aimpaired and the degree of injury of which support cable can be defined, define which bearing and there occurs generalized displacement and numerical value thereof, namely achieve damaged cable and the generalized displacement of support identification of Cable Structure;

M. get back to e step, start the circulation next time being walked to m step by e.