CN111696103B - Constant-load linear mapping method of single-span simple girder bridge under uninterrupted traffic condition - Google Patents
Constant-load linear mapping method of single-span simple girder bridge under uninterrupted traffic condition Download PDFInfo
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Abstract
The invention discloses a constant load linear mapping method of a single-span simple girder bridge under the condition of no traffic interruption, and relates to the technical field of bridge state detection; the method comprises the following steps: data acquisition is carried out on each detection identification point; performing multi-scale wavelet decomposition on low frequency data in the acquired vertical dynamic displacement time-course curve to obtain a quasi-static component of the time-course curve; re-acquisition of t 1 、t 2 Determining t by combining the position parameter of the identification point and the quasi-static component of the vehicle at the moment 2 Moment vehicle load deflection effect; re-acquisition of t 2 Instantaneous deflection of each detection mark point at moment and combining t 2 And obtaining constant load deflection by the vehicle load deflection effect at the moment, thereby forming a constant load line shape of the bridge. The invention can realize the mapping of the constant load line shape of the bridge under the condition that the bicycle passes through the bridge, compared with the traditional/novel static deflection measuring method in the prior art, the invention does not need to seal traffic, has more flexible, simple and convenient and efficient detection, and greatly reduces the detection cost.
Description
Technical Field
The invention belongs to the technical field of bridge state detection, and particularly relates to a constant load linear mapping method of a single-span simple girder bridge under the condition of no interruption of traffic.
Background
The line shape of the bridge is required to be measured regularly in the industry so as to detect the stability and the safety of the bridge, the measurement is mainly static deflection measurement, and in order to detect the safety of personnel and avoid the influence of live load disturbance, the elevation data of different positions of the bridge are required to be acquired by utilizing a plurality of measuring instruments under the condition that the bridge has no vehicle load, and the deflection of the bridge is obtained by the corresponding deflection algorithm. The conventional static deflection measurement method commonly used at present comprises methods such as a suspension hammer method, an electronic displacement meter method, a level gauge measuring method, a GPS positioning method, a total station observation method, a communicating pipe sensing technology, an inclinometer measuring method, a static level gauge system and the like; with the continuous development of technology, a batch of novel static deflection measurement technologies are developed in recent years, and the technologies mainly comprise radar interferometry technology, three-dimensional laser scanning technology, an optical fiber linear rapid measurement system and close-range photogrammetry technology.
Taking a leveling method as an example, a realization scheme of measuring the line shape by a traditional method is briefly described (refer to TNJC/SSXZ/01-02/07 in the rule of bridge line shape detection): step 1: and marking specific positions of the abutment and the pier on the bridge deck by using chalks. The bridge deck structure of beam bridge span structure, arch type and cable tower structure is characterized by that it is favourable for laying measuring points along longitudinal breaking plane of bridge, and three side lines of bridge-dividing axis and up-and-down edge line of roadway are used for making closed leveling measurement according to the level measurement requirements of second class engineering. The measuring points should be arranged on the span bisection section of the bridge span or deck structure. Step 2: the precise level gauge is erected on a smooth road surface for leveling, the tower ruler is erected on a measuring position, and the elevation of a leveling point near a route is used as a reference. The elevation reading of the measurement point is measured and recorded and is denoted by m. The leveling principle is shown in fig. 1. Step 3: all the measurement points were measured continuously and closed to the level point. Step 4: and calculating the elevation of each point of the bridge deck, and drawing a longitudinal line graph of the bridge deck structure according to the positions and the elevation of each point.
Although the above methods are developed for bridge deflection measurement, none of the above exceptions belongs to bridge static deflection measurement, and cannot be applied under the condition of bridge traffic, so traffic needs to be closed, and the process involves approval, report and traffic broadcasting, and cooperation of road administration personnel, traffic police, maintenance departments and other personnel, thereby generating higher time cost, personnel cost and economic cost, and being unfavorable for flexible, efficient and low-cost measurement requirements.
Disclosure of Invention
In view of the above, an object of the present invention is to provide a constant load linear mapping method of a single span simple beam bridge under the condition of no interruption of traffic, so as to solve the requirements of closed traffic in the prior art for measuring the deflection of the bridge Liang Jingtai, which is not beneficial to the flexible, efficient and low-cost measurement.
In some illustrative embodiments, the single span simply supportedA constant load linear mapping method of a beam bridge under the condition of no traffic interruption comprises the following steps: sequentially setting a plurality of detection mark points along the span direction of the bridge, and acquiring a vertical dynamic displacement time course curve of each detection mark point when a bicycle passes through the bridge; performing multi-scale wavelet decomposition on the low frequency data in each vertical dynamic displacement time-course curve to obtain quasi-static components of the vertical dynamic displacement time-course curve; obtaining t 1 Time sum t 2 The position parameters of the vehicle at the moment are combined with the position parameters of all detection mark points and the quasi-static components of the vertical dynamic displacement time course curve to calculate and determine t 2 Moment vehicle load deflection effect; obtaining t 2 Instantaneous deflection of each detection mark point at moment and combining t 2 And calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting the bridge to form a constant load line shape based on the constant load deflection of the bridge.
In some alternative embodiments, the multiscale wavelet decomposition specifically uses sym7 wavelet functions.
In some alternative embodiments, at the acquisition t 1 Time sum t 2 Before the position parameter of the vehicle at the moment, the method comprises the following steps: acquiring video data of a bicycle passing through a bridge, wherein the video data is synchronous with the vertical dynamic displacement time-course curve; the acquisition t 1 Time sum t 2 The position parameters of the vehicle at the moment concretely include: based on the video data, t is extracted respectively 1 First image data of time and t 2 Second image data of the time; respectively carrying out geometric feature recognition on vehicles in the first image data and the second image data, and determining the centroids of the vehicles in the first image data and the second image data; and determining the position parameters of the vehicle in the first image data and the second image data according to the determined relative positions of the centroid of the vehicle and the bridge.
In some optional embodiments, the position parameter of each detection mark point and the quasi-static component of the vertical dynamic displacement time-course curve are combined to calculate, and t is determined 2 The moment vehicle load deflection effect specifically comprises:according to t 1 Time sum t 2 Determining t by using the position parameter of the vehicle at the moment and the position parameters of all detection mark points 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i The method comprises the steps of carrying out a first treatment on the surface of the Determining t according to the following formula 2 Moment vehicle load deflection effect:
wherein ,
at t 2 Vehicle load deflection of the ith detection mark point at moment i, < ->
At t 2 The ith detection mark point at the moment relative to t 1 The change of the load deflection of the vehicle at the moment.
In some alternative embodiments, the method according to t 1 Time sum t 2 Determining t by using position parameters of vehicle at moment and position parameters of detection identification points 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i The method specifically comprises the following steps: determining t 1 Horizontal distance a of the vehicle from the first end of the bridge at the moment 1 And a horizontal distance b from the second end of the bridge 1 、t 2 Horizontal distance a of the vehicle from the first end of the bridge at moment 2 And a horizontal distance b from the second end of the bridge 2 The horizontal distance x of the ith detection mark point from the first end of the bridge i The method comprises the steps of carrying out a first treatment on the surface of the For t above 1 Time sum t 2 Non-dimensionality processing is carried out on the time position parameters to enable
Non-dimensionalization processing is carried out on the position parameters of the detection mark points to enable +.>
When x is i ＜a 1 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When a is 1 ＜x i ＜a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When x is i ＞a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
wherein ,n1 Is t after dimensionless treatment 1 Position parameters of the vehicle at time, n 2 Is t after dimensionless treatment 2 Position parameters of the vehicle at the moment, m i For the position parameter of the ith detection mark point after dimensionless treatment,
at t 1 And detecting the vehicle load deflection of the identification point at the ith moment.
In some alternative embodiments, the acquiring t 2 The instantaneous deflection of each detection mark point at the moment specifically comprises: for t 2 Performing geometric feature recognition on each detection identification point in the second image data at the moment, and determining the centroid of each detection identification point; from the determinationThe relative position of the centroid of the detection mark point and the bridge is determined to be t 2 Instantaneous deflection of each detection mark point at moment
In some alternative embodiments, the binding t 2 Calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting lines based on the constant load deflection of the bridge to form a constant load line shape, wherein the method specifically comprises the following steps of: according to t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Moment vehicle load deflection effect, determining t 2 Constant load deflection of each detection mark point at moment; and forming a constant load line shape of the bridge according to the constant load deflection of each detection mark point.
In some alternative embodiments, the method according to t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Moment vehicle load deflection effect, determining t 2 Constant load deflection of each detection mark point at moment specifically comprises: and calculating and determining the constant load deflection of each detection identification point according to the following formula:
wherein ,y0 (x i ) For the constant load deflection of the ith detection mark point,
at t 2 Instant flexibility of the i-th detection mark point at moment, < >>
At t 2 And detecting the vehicle load deflection of the identification point at the ith moment.
In some optional embodiments, the sequentially setting a plurality of detection identification points along the span direction of the bridge specifically includes: setting a midspan measuring point by taking the center of the bridge and taking the midspan measuring point as the center to twoA plurality of equidistant other measuring points are arranged on the side; the t is 1 To measure the initial time, t 2 The moment is the moment when the vehicle load generates maximum deflection at the mid-span measuring point.
In some optional embodiments, a plurality of other measuring points are equidistant to two sides with the midspan measuring point as a center, which specifically includes: and the other measuring points are distributed and arranged by taking the midspan measuring point as a center and selecting an octant or a hexadecimal point according to the length of the midspan.
Compared with the prior art, the invention has the following technical advantages:
the bridge constant load linear mapping method adopts the bridge dynamic deflection measurement technology, can realize the bridge constant load linear mapping under the condition that a bicycle passes through the bridge, and compared with the traditional/novel static deflection measurement method in the prior art, the method does not need to seal traffic, has more flexible, simple and convenient detection, is high-efficient, and greatly reduces the detection cost.
Drawings
FIG. 1 is a schematic diagram of a prior art level measurement principle;
FIG. 2 is a flow chart of a constant load linear mapping method in an embodiment of the invention;
FIG. 3 is a schematic diagram of a vehicle-bridge relationship state of a vehicle at any time in a period t according to an embodiment of the present invention;
FIG. 4 is a schematic illustration of a theoretical deflection curve of a bridge without a vehicle in an embodiment of the invention;
FIG. 5 is a vehicle at t in an embodiment of the invention 1 A schematic diagram of the relationship state between the vehicle and the bridge at moment;
FIG. 6 is a vehicle at t in an embodiment of the invention 2 A schematic diagram of the relationship state between the vehicle and the bridge at moment;
FIG. 7 is a detailed flow chart of an example of a constant load linear mapping method in an embodiment of the invention;
FIG. 8 is a deflection curve of the bridge in the dead weight state in the verification example in the embodiment of the present invention;
FIG. 9 is a plot of raw displacement time course for a test point # 5 in a verification example in an embodiment of the present invention;
FIG. 10 is a dynamic component of the original displacement time-course curve for the # 5 measurement in the verification example in an embodiment of the present invention;
FIG. 11 is a quasi-static component of the original displacement time-course curve for the # 5 measurement point in the verification example in an embodiment of the present invention;
FIG. 12 is t in an example of verification in an embodiment of the invention 1 A key frame image of the moment;
FIG. 13 is t in an example of verification in an embodiment of the invention 2 A key frame image of the moment;
fig. 14 is a constant load line shape of the bridge obtained in the verification example in the embodiment of the present invention.
Detailed Description
The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. The scope of embodiments of the invention encompasses the full ambit of the claims, as well as all available equivalents of the claims. These embodiments of the invention may be referred to herein, individually or collectively, by the term "invention" merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept if more than one is in fact disclosed.
The term "bridge line": the connection of the elevation of the bridge profile is generally shown graphically. The coordinate system is usually defined firstly, a support at one end of the bridge is used as a coordinate origin, the trend of the support and the bridge is used as an X axis, the vertical upward direction is used as a Y axis, and the connecting line of the vertical displacement of each section of the bridge is in a bridge line shape.
The term "constant load": the dead weight of the bridge structure.
The term "constant load line": geometrical changes due to the dead weight of the structure.
The term "live load deflection effect": for the deflection effect caused by loads such as vehicles, temperature, wind and the like, the inspection time is short, and the environmental conditions such as the temperature, the wind and the like are basically in a non-change state, so that the influence on deflection change is extremely low and negligible, and the live load deflection effect in the application mainly considers the vehicle load deflection effect.
It should be noted that, all the technical features in the embodiments of the present invention may be combined with each other without conflict.
The embodiment of the invention discloses a constant load linear mapping method of a single-span simple branch bridge under the condition of no interruption of traffic, in particular to a flow chart of the constant load linear mapping method of the single-span simple branch bridge under the condition of no interruption of traffic in the embodiment of the invention, as shown in fig. 2, wherein fig. 2 is a flow chart of the constant load linear mapping method of the single-span simple branch bridge under the condition of no interruption of traffic; the constant load linear mapping method of the single span simple girder bridge under the condition of no traffic interruption comprises the following steps:
step S11, sequentially setting a plurality of detection mark points along the span direction of the bridge, and acquiring a vertical dynamic displacement time course curve of each detection mark point when a bicycle passes through the bridge;
step S12, performing multi-scale wavelet decomposition on the low frequency data in each vertical dynamic displacement time-course curve to obtain quasi-static components of the vertical dynamic displacement time-course curve;
step S13, obtaining t 1 Time sum t 2 The position parameters of the vehicle at the moment are combined with the position parameters of all detection mark points and the quasi-static components of the vertical dynamic displacement time course curve to calculate and determine t 2 Moment vehicle load deflection effect;
step S14, obtaining t 2 Instantaneous deflection of each detection mark point at moment and combining t 2 And calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting the bridge to form a constant load line shape based on the constant load deflection of the bridge.
The bridge constant load linear mapping method adopts the bridge dynamic deflection measurement technology, can realize the bridge constant load linear mapping under the condition that a bicycle passes through the bridge, and compared with the traditional/novel static deflection measurement method in the prior art, the method does not need to seal traffic, has more flexible, simple and convenient detection, is high-efficient, and greatly reduces the detection cost.
In the step S11 in the embodiment of the invention, the detection identification points can be specifically selected from detection identification plates or natural identification points with obvious texture characteristics on the bridge to be detected; during night detection, luminous marks can be arranged to serve as detection mark points. The position distribution of the detection identification points covers the whole span of the bridge to be detected, so that the follow-up acquisition of the more complete constant load line shape of the whole bridge to be detected is facilitated. For the bridge to be tested, the number of the detection identification points can be selected to be proper according to the span length of the bridge, and the more the number of the detection identification points is, the higher the accuracy of the obtained constant load line shape is, but the higher the requirements on measuring instruments and computing equipment are; on the other hand, the detection mark points can be distributed at equal intervals when the detection mark points are arranged, so that a constant load line shape with gentle and accurate change is obtained, and the problem of abnormal mutation of a certain section is avoided.
Preferably, the detection identification points can be arranged at equal intervals along the longitudinal direction of the bridge; the detection identification points comprise identification points positioned at the initial position of the bridge and identification points positioned at the tail position of the bridge, and the number of the detection identification points is not more than 33 at most.
Further, the detection mark point can be firstly provided with a midspan measuring point of the bridge, then a plurality of equidistant other measuring points are arranged on two sides by taking the midspan measuring point as a center, the other measuring points cover the starting position and the tail position of the bridge, and the bridge is distributed by 8 points, 10 points and 16 points.
In the step S11 in the embodiment of the present invention, a vertical dynamic displacement time interval curve of each detection mark point when a bicycle passes through a bridge is obtained, and in particular, video data of the bicycle passing through the bridge and a vertical dynamic displacement time interval curve of each detection mark point within the whole period t of time when the bicycle passes through the bridge can be synchronously obtained through a bridge deflection detector. The video data should include bridge, vehicle and detection mark points.
The vertical dynamic displacement time course curve of each detection mark point refers to the variation of vertical displacement generated by each detection mark point along with the displacement of the vehicle on the bridge in time t;
further, the applicant has found that the vertical dynamic displacement time-course curve of the detected identification points is a time-dependent sequence, which can be decomposed onto different frequency bands by discrete wavelet transformation. For example, in the field of health monitoring, in the past, a learner proposed to separate the actually measured response history information of the bridge structure into transient and gradual change information by using a wavelet multi-scale analysis method, wherein the deflection effect caused by temperature is in a low frequency band corresponding to the gradual change information, and the deflection effect caused by vehicle load is in a high frequency band corresponding to the transient information, and the two information can be effectively distinguished by utilizing multi-scale wavelet decomposition. In the method adopted by the application, as the test time is short, only the deflection change condition in the range of less than one vehicle driving period (time t) is recorded, the influence of temperature and constant load on deflection is not changed, the vertical dynamic displacement is mainly caused by vehicle load, wavelet decomposition is carried out on the data, the obtained low-frequency data is the quasi-static deflection effect of the vehicle load, the high-frequency data is the vibration effect caused by vehicle motion and can be used as noise removal, thereby eliminating the secondary influence of the vehicle motion on the deflection change of the bridge, mainly considering the main influence of the vehicle load on the deflection change of the bridge, and being beneficial to improving the accuracy of the bridge line shape formed subsequently. Therefore, the characteristics of the expression signals can be decomposed and reconstructed on the vertical dynamic displacement time-course curve of each detected identification point based on a multi-scale analysis method.
Therefore, in the embodiment of the present invention, in step S12, multi-scale wavelet decomposition is performed on the low frequency data in the vertical dynamic displacement time-course curve of each detection identification point to obtain a quasi-static component of the vertical dynamic displacement time-course curve of each detection identification point, and in step S12, the low frequency data of the vertical dynamic displacement time-course curve of each detection identification point is continuously decomposed to screen out the high frequency data, so as to improve the accuracy of the obtained change amount of the bridge deflection effect caused by the vehicle load.
The method comprises the following steps of: selecting a proper orthogonal wavelet base as a wavelet function; selecting a proper decomposition layer number J and carrying out wavelet transformation decomposition on the low-frequency signal containing noise to the J layer; and reconstructing a quasi-static component of the signal by using the approximation coefficient decomposed into the J layer, and taking the quasi-static component as the bridge deflection variable quantity caused by the vehicle load.
Further, the wavelet function of the present application may be a Symlet wavelet function, which is an approximately symmetric wavelet function proposed by inpriddaubechies, generally denoted as symN (n=2, 3, …, 8). The synN wavelet function has good regularity and symmetry, and can reduce phase distortion when analyzing and reconstructing signals to a certain extent. In some other embodiments, other wavelet functions may be used in the present application.
Preferably, the wavelet basis function is sym7, and after decomposing into 7 layers, the quasistatic components Deltaw (t, x) of the load deflection effect are obtained by recombination i ) And a dynamic component, wherein t is an acquisition time (i.e. the time t for the vehicle to pass through the bridge), i=1, 2 … n, and n is the number of detection identification points.
In step S13 of the embodiment of the present invention, t is obtained 1 Time sum t 2 The position parameters of the vehicle at the moment are combined with the position parameters of all detection identification points and the quasi-static components of the vertical dynamic displacement time course curve to calculate, and the vehicle load deflection effect at the moment t2 is determined; wherein t is 1 Time sum t 2 The moment of time can be two optional different moments of time t of the vehicle passing the bridge, in general t 2 Time at t 1 After the moment in time.
T in this example 1 Time sum t 2 The position parameters of the vehicle at the moment can be respectively captured and extracted from the acquired video data 1 Time sum t 2 Moment in time key frame image, i.e. t 1 First image data of time and t 2 Second image data of the time; then determining the position parameters of the vehicle by analyzing the relative position relation between the vehicle and the bridge in the image data; wherein, canDetermining the centroid of the vehicle by means of the detection experience of the measuring/analyzing personnel, so that the centroid of the vehicle determines the position parameters of the bridge; alternatively, the geometric center of the vehicle may be determined by image feature extraction. Wherein the video data used can be obtained in the preceding steps.
Preferably, the present application obtains t 1 Time sum t 2 The position parameters of the vehicle at the moment concretely include: based on the video data, t is extracted respectively 1 First image data of time and t 2 Second image data of the time; respectively carrying out geometric feature recognition on vehicles in the first image data and the second image data, and determining the centroids of the vehicles in the first image data and the second image data; and determining the position parameters of the vehicle in the first image data and the second image data according to the determined relative positions of the centroid of the vehicle and the bridge. The method and the device only aim at the situation of a single vehicle, so that the vehicle in the key frame image can be identified only according to the information such as the color, the shape and the size of the vehicle. Specifically, centroid recognition of a vehicle can use the principle of background differences to recognize the centroid of the vehicle by employing an open source code in opencv. In some other embodiments, other digital image processing methods may be used to identify the centroid of the vehicle, such as feature extraction, SVM classification, deep learning, etc. may be implemented.
In some embodiments, the position parameter of each detection mark point may be obtained by detecting in the same manner as the position parameter of the vehicle, or when the detection mark point is set, the center of the detection mark point is used as its centroid, that is, the position parameter of the detection mark point is a known quantity, without measurement.
In step S13, the quasi-static components of the vertical dynamic displacement time-course curve and the position parameters of the detection mark points are combined to calculate, and t is determined 2 The moment vehicle load deflection effect specifically comprises: according to t 1 Time sum t 2 Determining t by using the position parameter of the vehicle at the moment and the position parameters of all detection mark points 1 Moment vehicle load deflection effect and t 2 Moment-of-time vehicle load deflection effect ratioN i The method comprises the steps of carrying out a first treatment on the surface of the Determining t according to the following formula 2 Moment vehicle load deflection effect:
wherein ,
at t 2 Vehicle load deflection of the ith detection mark point at moment i, < ->
At t 2 The ith detection mark point at the moment relative to t 1 The change of the load deflection of the vehicle at the moment.
"x" in the embodiment of the present invention i "represents the horizontal position of the ith detection mark point relative to the bridge, in some embodiments, it may be represented by specific coordinates relative to the bridge, so as to
For example, concretely denote t 2 Position x of i-th detection mark point at moment i On-board load deflection, i.e. t 2 Vehicle load deflection of ith detection mark point at moment, other AND' x i The "relevant parameters" are the same as those understood above and will not be described again here.
Wherein, in the above calculation,
the quasi-static component of the vertical dynamic displacement time-course curve of the detection mark point can be extracted at t 2 Time sum t 1 The change of the load deflection of the vehicle at the moment is obtained.
Fig. 3 is a schematic diagram showing a relationship state between a vehicle and a bridge at any time in a period t in an embodiment of the present invention; FIG. 4 is a schematic illustration of a bridge deflection curve without a vehicle in accordance with an embodiment of the present invention; FIG. 5 is a schematic illustration of a vehicle at t in an embodiment of the invention 1 Vehicle and bridge at momentA relationship state diagram; FIG. 6 is a schematic illustration of a vehicle at t in an embodiment of the invention 2 Schematic diagram of the relation state between the vehicle and the bridge at moment. Wherein, def1 is bridge constant load deflection linear, def2 is t 1 Instantaneous deflection line shape of bridge under moment, def3 is t 2 Instantaneous deflection line shape of the bridge at any time; wherein, the bridge constant load deflection schematic diagram of fig. 4 is used to match fig. 5 and 6, so that those skilled in the art can understand that the bridge is t when no vehicle is present 1 Time sum t 2 The state of the moment in time, and thus the present application, is more quickly understood.
Referring to FIGS. 3-6, according to t 1 Time sum t 2 Determining t by using position parameters of vehicle at moment and position parameters of detection identification points 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i The method specifically comprises the following steps: determining t 1 Horizontal distance a of the vehicle from the first end of the bridge at the moment 1 And a horizontal distance b from the second end of the bridge 1 、t 2 Horizontal distance a of the vehicle from the first end of the bridge at moment 2 And a horizontal distance b from the second end of the bridge 2 The horizontal distance x of the ith detection mark point from the first end of the bridge i The method comprises the steps of carrying out a first treatment on the surface of the For t above 1 Time sum t 2 Non-dimensionality processing is carried out on the time position parameters to enable
Non-dimensionalization processing is carried out on the position parameters of the detection mark points to enable +.>
When x is i ＜a 1 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When a is 1 ＜x i ＜a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When x is i ＞a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio M:
wherein ,n1 Is t after dimensionless treatment 1 Position parameters of the vehicle at time, n 2 Is t after dimensionless treatment 2 Position parameters of the vehicle at the moment, m i And (5) detecting the position parameter of the mark point for the ith detection after dimensionless treatment.
Specifically, with continuing to refer to fig. 3 for an example, in the case that the vehicle travels to the point D of the bridge, according to the theory of material mechanics, the deflection curve equation of the single-span simple beam under the action of the concentrated load can be solved as follows:
for the AD section, the deflection curve equation is:
for the DB section, the deflection curve equation is:
wherein F represents the load of the vehicle, a and b represent the action positions of the load of the vehicle as shown in the figure, E is the elastic modulus, I is the section moment of inertia of the main beam, and l is the span.
The applicant has found that the two above can be utilized firstEquation solving
and
Conversion relation between (i.e. t 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ) Then with N i and
Obtaining t through calculation 2 Moment vehicle load deflection; the calculation mode does not need to consider the vehicle load F, the elastic modulus E and the main beam section moment of inertia I, so that the acquisition difficulty of the application on partial data parameters can be reduced, and the feasibility and the high efficiency of the mapping method are realized.
In some alternative embodiments, the acquiring t 2 The instantaneous deflection of each detection mark point at the moment specifically comprises: for t 2 Performing geometric feature recognition on each detection identification point in the second image data at the moment, and determining the centroid of each detection identification point; determining t according to the determined relative positions of the centroid of the detection mark point and the bridge 2 Instantaneous deflection of each detection mark point at moment
In some alternative embodiments, the binding t 2 Calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting lines based on the constant load deflection of the bridge to form a constant load line shape, wherein the method specifically comprises the following steps of: according to t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Moment vehicle load deflection effect, determining t 2 Constant load deflection of each detection mark point at moment; and forming a constant load line shape of the bridge according to the constant load deflection of each detection mark point.
In some embodiments, the constant load line shape of the bridge is formed according to the constant load deflection of each detection identification point, a coordinate system can be established according to the constant load deflection of each detection identification point, and then the constant load deflection of each detection identification point in the coordinate system is connected to form the constant load line shape of the bridge. Preferably, the coordinate system is established by the end point of the bridge before the relative position of the vehicle load and each detection identification point relative to the bridge is determined, so that the relative position of the vehicle load and each detection identification point relative to the bridge is determined on the basis of the coordinate system, and the coordinate system is not required to be established independently.
Said according to t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Moment vehicle load deflection effect, determining t 2 Constant load deflection of each detection mark point at moment specifically comprises: and calculating and determining the constant load deflection of each detection identification point according to the following formula:
wherein ,y0 (x i ) For the constant load deflection of the ith detection mark point,
at t 2 Instant flexibility of the i-th detection mark point at moment, < >>
At t 2 And detecting the vehicle load deflection of the identification point at the ith moment.
In some embodiments, the plurality of equidistant detection identification points are sequentially arranged along the span direction of the bridge, and specifically include: setting a midspan measuring point by taking the center of the bridge, and setting a plurality of equidistant other measuring points to two sides by taking the midspan measuring point as the center; t is t 2 The moment when the maximum deflection is generated at the midspan measuring point by the vehicle load is selected, the deflection of the bridge is also maximum at the moment, and the obtained constant load line shape of the bridge is more accurate and more visual.
In order to facilitate a person skilled in the art to quickly understand the technical solution of the present application, detailed steps and derivation processes of the present application are described herein in detail, as shown in fig. 7, and fig. 7 is a detailed flowchart of a preferred embodiment of the present invention.
Step 1: and (5) data acquisition. And acquiring main beam vibration video data and a multipoint vertical dynamic displacement time-course curve under the condition of bicycle passing by adopting a BJQN-X bridge deflection detector.
Step 2: and decomposing the vehicle load deflection effect. Performing multi-scale wavelet decomposition on vertical dynamic displacement time-course data (namely a vertical dynamic displacement time-course curve) of the detection mark point to obtain a quasi-static component and a dynamic component, wherein the quasi-static component is taken as a main effect of load deflection and is taken as deflection variation delta w (t, x) i )。
Step 3: selecting t 1 Time sum t 2 At the moment, determining the vehicle load deflection relative to t at the moment t2 of each detection mark point 1 Deflection change amount at moment;
wherein ,t1 Time is preferably zero (i.e., t=0), t 2 The moment is preferably the moment when the bridge generates maximum deformation under the action of the vehicle. By taking the time "zero" as t 1 Can reduce t 1 Difficulty in selecting time is favorable for determining t 2 And directly determining the deflection change quantity of the total vehicle load deflection at the moment t2 of each detection mark point relative to the deflection change quantity at the moment t 1.
In particular, according to the principle of material mechanics, the mid-span measuring point can be used
Deflection change Δw max The corresponding time is taken as t 2 。
The measuring points can be arranged in the midspan, namely 1/2 position, other measuring points are arranged according to the requirement of the equal dividing points, and the eight dividing points or the sixteen dividing points can be selected according to the length of the midspan.
At mid-span measuring points
In the curve, Δw is found max And corresponding to itTime t 2 Namely, the moment when the bridge generates maximum deformation under the vehicle-mounted action.
Step 4: key frame vehicle location information is obtained from the video data. For the measurement video, the measurement initial time t is extracted 1 And the moment t of maximum deformation in midspan 2 Key frame image of (2) by digital image processing method, for t 1 and t2 The key frame image is used for vehicle identification, the vehicle centroid position is used for representing the vehicle position, and t is obtained respectively 1 and t2 Coordinate a of moment vehicle position forward-bridge direction 1 and a2 。
The formula in the application is suitable for deflection conversion when a vehicle passes through a bridge, so that license plates are not required to be identified, and the vehicle in a key frame image is only required to be identified according to information such as the color, the shape and the size of the vehicle.
Implemented using open source code in opencv. The principle of background differences can be used to identify vehicles; the identification of the geometric features of the vehicle in the application by using the open source code in opencv belongs to a conventional method in the field, and is not described herein.
Step 5: solving deflection effect caused by vehicle load
Measuring dynamic deflection of a marked point on a beam during traffic conditions, at the beginning of the measurement (t 1 Moment) the vehicle has made the initial downwarping of the bridge marking points
Time t when maximum displacement is generated at mid-span measuring point 2 Quasi-static component of load deflection effect detected by instrument +.>
Is the relation of each measuring point to t 1 The moment deflection change amount should be equal to the difference value between the actual vehicle load deflection effect and the initial deflection effect, namely:
as shown in fig. 3, according to the theory of material mechanics, the deflection curve equation of the single-span simple beam under the action of concentrated load can be solved as follows:
for the AD section, the deflection curve equation is:
for the DB section, the deflection curve equation is:
wherein F represents the load of the vehicle, a and b represent the action positions of the load of the vehicle as shown in the figure, E is the elastic modulus, I is the section moment of inertia of the main beam, and l is the span.
Can be solved according to the formula (2) and the formula (3)
and
Conversion relation between the two. Definition t 1 The vehicle position at time is a 1 、b 1 ，t 2 The vehicle position at time is a 2 、b 2 The method comprises the steps of carrying out a first treatment on the surface of the Wherein the horizontal distance x between the ith detection identification point and the first end of the bridge i ；
For dimensionless treatment, let
n is the number of the identification points
When x is i ＜a 1 In the time-course of which the first and second contact surfaces,
and
Can be represented by formula (2)The ratio of the two is the proportionality coefficient N i Derived by the formula:
when a is 1 ＜x i ＜a 2 In the time-course of which the first and second contact surfaces,
and
Can be expressed by the formulas (2) and (3), and the ratio of the two is a proportionality coefficient N i Derived by the formula:
when x is i ＞a 2 In the time-course of which the first and second contact surfaces,
and
Can be expressed by the formula (3), the ratio of the two is a proportional coefficient N i Derived by the formula:
then
Substitution (1), conversion to obtain
Step 6: bridge extraction from video dataInstantaneous linear shape. Extracting t from video data 2 Performing digital image processing on a single-frame image at a moment, extracting identification points, and converting to obtain instantaneous line shapes of bridges
The marking points can be regular black-white circular rings, and are o Extracting the identified point centroid by pencv programming, wherein o The open source code in pencv realizes the geometric feature recognition of the identification point in the application, which belongs to a conventional means in the field and is not described herein.
The centroid coordinates of the identification points are identified through the method, the pixel coordinates of the center points of the identification plates are obtained, and the pixel coordinates are converted into actual coordinate values according to the scale factors. Taking the connecting line of the A point and the B point of the support as an X axis (the B point is pointed by the A point to be in the positive direction), taking the vertical upward direction as the positive direction of the Y axis, and taking the Y value of each point as t 2 Instantaneous deflection at time
(i=1, 2 … n, n is the number of identification points).
Step 7: subtracting the deflection variation from the instantaneous deflection to obtain constant load deflection y 0 (x i )
The instantaneous deflection comprises constant load deflection effect, temperature deflection effect, creep deflection effect and vehicle load effect, wherein the deflection effect caused by temperature and creep is long period effect, and the instantaneous deflection can be ignored in the short-time measurement adopted by the patent
Consider only constant load deflection effect y 0 (x i ) And vehicle load effect->
It can be approximated that the constant load deflection can be obtained by: />
Step 8: and (5) connecting the multi-point constant load deflection lines to obtain a constant load line shape.
Y of each identification point 0 (x i ) Connecting the wires and matching with X, Y coordinate axes to obtain the constant load line shape.
Examples of the calculation of the method of the present application are given below:
the constant load deflection of the real bridge is not easy to obtain, the indoor test factors are controllable, and the theoretical calculation and the test method are relatively easy to implement, so that the method is verified on a single-span test beam. A steel ruler is adopted to simulate a simple beam, a signboard is arranged at an octant of the simple beam, and a weight simulation trolley is adopted to demonstrate the implementation process of the method.
1) Obtaining an initial line shape. To verify the accuracy of the algorithm, the initial line shape is measured at the beginning of the test.
As shown in fig. 8, the parameters of each point are shown in the following table:
2) Step 1: data acquisition during vehicle passing
And (3) using weights to simulate a trolley, passing the trolley on the simple beam, and collecting multipoint dynamic deflection data and videos.
3) Step 2: load deflection effect decomposition
The wavelet basis function selected at this time is sym7, and after decomposing to 7 layers, the quasistatic components Deltaw (t, x) of the load deflection effect are respectively obtained by recombination i ) And a dynamic component, wherein t is the acquisition time, i=1, 2 … 9 is the number of identification points.
With mid-span measuring points (point # 5, i.e.)
Point) for example, fig. 9 shows the original displacement time curve of the 5# measuring point, fig. 10 shows the load dynamic component and quasi-static component time curve Δw (t, x) after decoupling reconstruction i )。
4) Step 3: finding a strideMiddle measuring point
Deflection change Δw max Corresponding time t 2
Analysis of the quasi-static component displacement time course curve of the 5# measurement point revealed that the maximum displacement was 19.43mm, which is the maximum deformation (the trolley (100 g weight) acting on the midspan) caused by t= 43.0076s of the 5# measurement point in the midspan, as shown in fig. 11. From this, it can be seen that the deflection change amount Δw of the mid-span measuring point max Corresponding time t 2 43.0076s.
5) Step 4: obtaining key frame vehicle location information from video data
Initial time t 1 And the moment t of maximum deformation in midspan 2 As shown in fig. 12 and 13, for t by digital image processing method 1 and t2 The key frame image is used for vehicle identification, the vehicle centroid position is used for representing the vehicle position, and t is obtained respectively 1 and t2 The vehicle position at the moment is along the bridge direction relative to the pixel coordinate a of the support 1 and a2 . Since the ratio is used in step 5, the actual coordinates do not need to be scaled. Wherein t is 1 Time a 1 251.746; t is t 2 Time a 2 514.002.
6) Step 5: solving deflection effect caused by vehicle load
a 1 、a 2 and xi It is known that n is obtained according to the formula 1 ，n 2 ，m i Bringing into formulas (4), (5) and (6) to obtain N in turn i Can be calculated according to the formula (7)
The calculation results are shown in the following table: />
Remarks: theoretically, when x i When 0, L, N i 0, but the coordinates of the signboard attached to the 0 and L positions during the test will vary with the deformation of the simple beam and cannot be exactly equal to 0 and L, so N in the test i The corresponding value is not 0.
7) Step 6: bridge transient line shape extraction from video data
Extracting t from video data 2 Performing digital image processing on a single-frame image at a moment, extracting identification points, and converting to obtain instantaneous line shapes of bridges
t 2 Instantaneous deflection value (mm) at time
8) Step 7: subtracting the deflection variation from the instantaneous deflection to obtain constant load deflection y 0 (x i )
And obtaining constant load deflection according to the formula (8).
Constant load deflection value (mm) of each point
9) Step 8: constant load line shape
The constant load line is shown in figure 14.
10 Verification):
comparison y 0 (x i ) And y is 0 0 (x i ) As shown in the table, the result shows that the method provided by the application can effectively map the constant load line shape under the traffic condition of the vehicle, and the accuracy is higher.
Verifying constant load deflection value (mm) of each point
Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.
Claims (8)
1. A constant load linear mapping method of a single span simple girder bridge under the condition of no traffic interruption is characterized by comprising the following steps:
sequentially setting a plurality of detection mark points along the span direction of the bridge, and acquiring a vertical dynamic displacement time course curve of each detection mark point when a bicycle passes through the bridge;
performing multi-scale wavelet decomposition on the low frequency data in each vertical dynamic displacement time-course curve to obtain quasi-static components of the vertical dynamic displacement time-course curve;
acquiring video data of a bicycle passing through a bridge, wherein the video data is synchronous with the vertical dynamic displacement time-course curve;
obtaining t 1 Time sum t 2 The position parameters of the vehicle at the moment concretely include: based on the video data, t is extracted respectively 1 First image data of time and t 2 Second image data of the time; respectively carrying out geometric feature recognition on vehicles in the first image data and the second image data, and determining the centroids of the vehicles in the first image data and the second image data; according to the determinedDetermining the position parameters of the vehicle in the first image data and the second image data according to the relative positions of the centroid of the vehicle and the bridge;
combining the position parameters of all detection mark points and the quasi-static components of the vertical dynamic displacement time-course curve to calculate and determine t 2 The moment vehicle load deflection effect specifically comprises: according to t 1 Time sum t 2 Determining t by using the position parameter of the vehicle at the moment and the position parameters of all detection mark points 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i The method comprises the steps of carrying out a first treatment on the surface of the Determining t according to the following formula 2 Moment vehicle load deflection effect:
wherein ,
at t 2 Vehicle load deflection of the ith detection mark point at moment i, < ->
At t 2 The ith detection mark point at the moment relative to t 1 The change amount of the load deflection of the vehicle at moment;
obtaining t 2 Instantaneous deflection of each detection mark point at moment and combining t 2 And calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting the bridge to form a constant load line shape based on the constant load deflection of the bridge.
2. The method of claim 1, wherein the multiscale wavelet decomposition is a sym7 wavelet function.
3. The constant load linear mapping method of claim 1, wherein the reference t 1 Time of day and time of dayt 2 Determining t by using position parameters of vehicle at moment and position parameters of detection identification points 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i The method specifically comprises the following steps:
determining t 1 Horizontal distance a of the vehicle from the first end of the bridge at the moment 1 And a horizontal distance b from the second end of the bridge 1 、t 2 Horizontal distance a of the vehicle from the first end of the bridge at moment 2 And a horizontal distance b from the second end of the bridge 2 The horizontal distance x of the ith detection mark point from the first end of the bridge i ；
For t above 1 Time sum t 2 Non-dimensionality processing is carried out on the time position parameters to enable
Non-dimensionalization processing is carried out on the position parameters of the detection mark points to enable +.>
When x is i ＜a 1 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When a is 1 ＜x i ＜a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
When x is i ＞a 2 When, the t is determined according to the following formula 1 Moment vehicle load deflection effect and t 2 Moment vehicle load deflection effect ratio N i ：
wherein ,n1 Is t after dimensionless treatment 1 Position parameters of the vehicle at time, n 2 Is t after dimensionless treatment 2 Position parameters of the vehicle at the moment, m i For the position parameter of the ith detection mark point after dimensionless treatment,
at t 1 And detecting the vehicle load deflection of the identification point at the ith moment.
4. The constant load linear mapping method of claim 1, wherein the acquiring t 2 The instantaneous deflection of each detection mark point at the moment specifically comprises:
for t 2 Performing geometric feature recognition on each detection identification point in the second image data at the moment, and determining the centroid of each detection identification point;
determining t according to the determined relative positions of the centroid of the detection mark point and the bridge 2 Instantaneous deflection of each detection mark point at moment
5. The constant load linear mapping method of claim 4, wherein the binding t 2 Calculating the moment vehicle load deflection effect to obtain the constant load deflection of the bridge, and connecting lines based on the constant load deflection of the bridge to form a constant load line shape, wherein the method specifically comprises the following steps of:
according to t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Time of dayThe vehicle load deflection effect of each detection mark point is determined;
and forming a constant load line shape of the bridge according to the constant load deflection of each detection mark point.
6. The constant load linear mapping method of claim 5, wherein the reference t 2 The instantaneous deflection sum t of each detection mark point at the moment 2 Moment vehicle load deflection effect, determining t 2 Constant load deflection of each detection mark point at moment specifically comprises:
and calculating and determining the constant load deflection of each detection identification point according to the following formula:
wherein ,y0 (χ i ) For the constant load deflection of the ith detection mark point,
at t 2 Instant flexibility of the i-th detection mark point at moment, < >>
At t 2 And detecting the vehicle load deflection of the identification point at the ith moment.
7. The constant load linear mapping method according to claim 1, wherein the sequentially arranging a plurality of detection identification points along the span direction of the bridge specifically comprises:
setting a midspan measuring point by taking the center of the bridge, and setting a plurality of equidistant other measuring points to two sides by taking the midspan measuring point as the center;
the time t1 is the initial measurement time;
the time t2 is the time when the vehicle load generates the maximum deflection at the mid-span measuring point.
8. The constant-load linear mapping method according to claim 7, wherein a plurality of other equidistant measuring points are arranged on two sides with the midspan measuring point as a center, and the method specifically comprises:
and the other measuring points are distributed and arranged by taking the midspan measuring point as a center and selecting an octant or a hexadecimal point according to the length of the midspan.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2444787A1 (en) * | 2010-10-22 | 2012-04-25 | Vilnius Gediminas Technical University | Method and device for bridge state evaluation using dynamic method |
| CN104537139A (en) * | 2014-11-10 | 2015-04-22 | 浙江大学 | Method for determining load effect of wind-wave coupling design of long-span bridge structure |
| CN104933285A (en) * | 2015-03-05 | 2015-09-23 | 西南交通大学 | Bridge field static load test evaluation method |
| CN105320596A (en) * | 2014-08-04 | 2016-02-10 | 中国铁道科学研究院铁道建筑研究所 | Bridge deflection test method based on inclinometers and system thereof |
| CN107025347A (en) * | 2017-04-10 | 2017-08-08 | 中铁二院工程集团有限责任公司 | A kind of multiple line railway bridge rail linear control method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105953996B (en) * | 2016-06-30 | 2017-04-19 | 东南大学 | Bridge detection and evaluation method and equipment based on impact vibration |
-
2020
- 2020-06-19 CN CN202010564587.4A patent/CN111696103B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2444787A1 (en) * | 2010-10-22 | 2012-04-25 | Vilnius Gediminas Technical University | Method and device for bridge state evaluation using dynamic method |
| CN105320596A (en) * | 2014-08-04 | 2016-02-10 | 中国铁道科学研究院铁道建筑研究所 | Bridge deflection test method based on inclinometers and system thereof |
| CN104537139A (en) * | 2014-11-10 | 2015-04-22 | 浙江大学 | Method for determining load effect of wind-wave coupling design of long-span bridge structure |
| CN104933285A (en) * | 2015-03-05 | 2015-09-23 | 西南交通大学 | Bridge field static load test evaluation method |
| CN107025347A (en) * | 2017-04-10 | 2017-08-08 | 中铁二院工程集团有限责任公司 | A kind of multiple line railway bridge rail linear control method |
Non-Patent Citations (2)
| Title |
|---|
| Noncontact photogrammetric measurement of vertical bridge deflection;Jáuregui D V et al.;《Journal of Bridge Engineering》;20031231;第212-222页 * |
| 基于阶梯刚度模式的PC梁开裂后挠度分析方法;王磊 等;《公路交通科技》;20181231;第63-68+81页 * |
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