CN109100098B - Method for remotely monitoring bridge deflection - Google Patents
Method for remotely monitoring bridge deflection Download PDFInfo
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- CN109100098B CN109100098B CN201810819867.8A CN201810819867A CN109100098B CN 109100098 B CN109100098 B CN 109100098B CN 201810819867 A CN201810819867 A CN 201810819867A CN 109100098 B CN109100098 B CN 109100098B
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- G01M5/00—Investigating the elasticity of structures, e.g. deflection of bridges or air-craft wings
- G01M5/0008—Investigating the elasticity of structures, e.g. deflection of bridges or air-craft wings of bridges
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- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
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Abstract
An opposed bridge deflection remote monitoring system comprises a liquid storage tank, a communicating pipe, a double-base-point calibration module, deflection measuring sub-modules, a data bus, a data synchronous collector, an industrial personal computer and a remote communication module, wherein the liquid storage tank and the double-base-point calibration module are arranged at the vertical section of the communicating pipe, and the horizontal section of the communicating pipe is communicated with each deflection measuring sub-module; the deflection measuring submodule comprises a stop valve, a first liquid storage pipe, a second liquid storage pipe, a first pressure sensor and a second pressure sensor, wherein the first liquid storage pipe and the second liquid storage pipe are respectively arranged at two ends of the stop valve and are horizontally and symmetrically arranged, and the second liquid storage pipe is connected with the horizontal section of the communicating pipe through a communicating pipe interface; the outer ends of the first liquid storage pipe and the second liquid storage pipe are respectively provided with a first pressure sensor and a second pressure sensor. According to the invention, by measuring the pressure values of the pressure sensors corresponding to the two opposite liquid storage pipes, the influence of liquid vibration in the connecting pipe on the measurement data is avoided, and the accurate measurement of the dynamic deflection is realized.
Description
Technical Field
The invention relates to the technical field of monitoring, in particular to a bridge deflection remote monitoring system and a monitoring method.
Background
Bridge deflection is an important parameter for measuring the service life and the health condition of a bridge. At present, in the aspect of monitoring the deflection of a bridge, scholars at home and abroad make a great deal of research, and the main monitoring methods include the following methods:
(1) leveling instrument method:
the deflection of the bridge is usually measured manually by using instruments such as a theodolite, a dial indicator and the like, but the method is difficult to accurately reflect the safety state of the bridge under the action of dynamic load generated by vehicle passing and cannot meet the requirement of long-term deflection automatic monitoring. The dynamic measurement is to monitor the deflection of the bridge in real time and on line, can accurately reflect the real-time deformation state of the bridge, can find the accident precursor of the bridge structure in time, avoid sudden disaster accidents and ensure the operation safety of the bridge.
(2) Deflection measurement method based on inclination mode:
the method mainly includes that a sensor for measuring an inclination angle is used for collecting the inclination angle of a main beam of the bridge, and then the deflection of the bridge is indirectly estimated through corresponding function calculation. The method is bridge deck operation, needs to interrupt traffic and manually assists, can only measure static deflection linearity, and cannot be used for long-term monitoring.
(3) Laser collimation sensitization:
the method uses a beam of collimated laser to shoot at the low sensitivity photographic negative film on the bridge to be side point, when the load is passed through, the photographic negative film is vibrated relatively to the laser beam, the trace of bridge vibration is left on the negative film, and the trace on the negative film is measured, so that the dynamic displacement of the bridge can be obtained. The method is simple to operate, but due to the divergence of light, the spot is large and the error is large when the distance is too far. And is susceptible to vibration interference.
(4) Deflection measurement method based on GPS:
the method is characterized in that one receiver is arranged on a fixed point (such as a forced centering point on a shore), the other receiver is arranged at a point (generally a midspan) with larger bridge deformation, the two receivers synchronously observe and receive signals of 4 or more satellites, and the positions of the deformation points relative to a reference point are calculated through a specific software system to obtain the deflection value of the beam. The GPS method has too complex function relation, more error sources, larger interference of positioning results by satellite clock error, receiver clock error, ionospheric delay, multipath error and the like, and weak practicability.
(5) Measuring the deflection of the robot:
the method comprises the steps of firstly installing a cooperative target, namely a prism, on a bridge, then respectively obtaining the geometric information of the cooperative target after loading by using a measuring robot, and finally calculating a corresponding displacement value. The method has high cost and complex operation, and is not suitable for conventional use.
(6) The deflection measurement method based on microwave interference comprises the following steps:
the method comprises the steps that a microwave interferometer is arranged on a non-deformation point, when a bridge is bent and deformed, microwaves emitted by the microwave interferometer are reflected back through a measuring point, and the deflection displacement change of a point to be measured is measured by identifying the phase difference of reflected waves; for the dynamic deflection measurement of ultra-large span flexible structure bridges (such as cable-stayed bridges and suspension bridges), because the transverse direction and the longitudinal direction of a beam body can generate obvious geometric deformation, and due to the inherent one-dimensional measurement characteristic of a microwave interferometer, if only a single radar is adopted, the influence of plane displacement on the deflection measurement cannot be eliminated.
(7) Deflection measurement method based on communicating pipe:
the method utilizes the principle of a communicating vessel, a communicating pipe is installed on a bridge according to the design requirement, the communicating pipe is kept to be communicated with pressure sensors and reference points at all detection points, anti-freezing liquid is filled in the whole communicating pipe, and when the bridge is deflected and deformed, the liquid level at the detection points is changed, and the deflection is indirectly obtained by collecting the liquid level change through a sensor. Because the liquid vibration in the communicating pipe can be caused to impact the sensor when the bridge vibrates, the measurement precision is difficult to guarantee under the dynamic complex environment.
In summary, the existing deflection measurement technology has many defects, and the provision of a new deflection measurement method and a special device has great practical significance.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide an opposed bridge deflection remote monitoring system and a monitoring method, wherein the method acquires multi-point pressure values through a deflection measuring submodule arranged on the lower surface of a bridge to obtain real-time deflection values of various measuring points of the bridge; the monitoring system has the advantages of high detection precision, simple structure and low system operation cost.
The problems of the invention are solved by the following technical scheme:
an opposed type bridge deflection remote monitoring system comprises a liquid storage tank, a communicating pipe, a double-base-point calibration module, deflection measurement sub-modules, a data bus, a data synchronization collector, an industrial personal computer and a remote communication module, wherein the liquid storage tank and the double-base-point calibration module are fixedly arranged on a pier, the deflection measurement sub-modules are provided with i, i is 1-N, the number of N is determined by the number of measuring points required in field installation, the deflection measurement sub-modules are uniformly arranged on a bridge floor, the lower surface of a bridge or the inside of a bridge box body at intervals, the communicating pipe comprises a vertical section and a horizontal section which are mutually communicated, the liquid storage tank and the double-base-point calibration module are arranged on the vertical section of the communicating pipe, and the horizontal section of the communicating pipe; the double-base-point calibration module, the deflection measurement submodule, the data synchronous collector, the industrial personal computer and the remote communication module are sequentially connected through a data bus;
the deflection measuring submodule comprises an internal measuring device, the internal measuring device is provided with a total pressure measuring module, the total pressure measuring module comprises a second liquid storage pipe and a second pressure sensor, and the second liquid storage pipe is communicated with the horizontal section of the communicating pipe through a communicating pipe joint arranged in the middle of the second liquid storage pipe; the second pressure sensor is arranged in the second liquid storage pipe and used for detecting the liquid pressure in the second liquid storage pipe.
The opposed type bridge deflection remote monitoring system is additionally provided with an impact pressure measuring module, the impact pressure measuring module and the total pressure measuring module have the same structure and are communicated together through a stop valve; the impact pressure measuring module comprises a first liquid storage pipe and a first pressure sensor, the first liquid storage pipe and a second liquid storage pipe are respectively arranged at two ends of the stop valve and are horizontally and symmetrically arranged, the first liquid storage pipe and the second liquid storage pipe are identical in size, shape and structure, the first liquid storage pipe is positioned at the left end, and the second liquid storage pipe is positioned at the right end; when the stop valve is closed, the first liquid storage pipe is a closed cavity, and the second liquid storage pipe is a communication cavity; the left end of first liquid storage pipe sets up first pressure sensor, and first pressure sensor is used for detecting the fluid pressure of first liquid storage pipe.
According to the opposed type bridge deflection remote monitoring system, the double-base-point calibration module comprises an upper pressure sensor and a lower pressure sensor, signal ends of the upper pressure sensor and the lower pressure sensor are communicated with the data synchronization collector through a data bus, the vertical distance between the upper pressure sensor and the lower pressure sensor is L, and the vertical distance L is 1/2 of the range of the upper pressure sensor and the lower pressure sensor, so that good linearity is guaranteed.
In the opposed type bridge deflection remote monitoring system, the height of the liquid storage tank at the top end of the vertical section of the communicating pipe is 20-40cm higher than that of the horizontal section, the extending direction of the horizontal section is the same as the length direction of the bridge, and the tail end of the horizontal section is provided with a first exhaust valve; and a second exhaust valve is arranged in the middle of the first liquid storage pipe and used for detecting that the first liquid storage pipe is filled with antifreeze.
In the opposed type bridge deflection remote monitoring system, the communicating pipe joint is a reducing communicating pipe joint, the inner diameter of the upper end of the communicating pipe joint is large, and the inner diameter of the lower end of the communicating pipe joint is small; and a damping film is arranged at the small inner diameter position of the lower end of the communicating pipe connector, and the distance between the communicating pipe connector and the second pressure sensor is 1 cm.
In the opposed type bridge deflection remote monitoring system, the deflection measuring submodule further comprises a sealing cover, and air pipe interfaces are respectively arranged at two ends of the sealing cover and are communicated with the liquid storage tank and other deflection measuring submodules through air pipes.
According to the opposed type bridge deflection remote monitoring system, the liquid storage tank is closed, the upper part of the liquid storage tank is provided with the air hole, and the air hole is connected with each deflection measuring submodule through the air pipe.
Above-mentioned opposed bridge amount of deflection remote monitoring system, first liquid reserve pipe and second liquid reserve pipe are the glossy aluminium alloy pipe of hollow inner wall, first pressure sensor and second pressure sensor pass through fastening screw fixed mounting respectively first liquid reserve pipe and second liquid reserve pipe outer end, all be provided with the lock washer between first pressure sensor and the first liquid reserve pipe and between second pressure sensor and the second liquid reserve pipe.
A method for realizing remote monitoring of bridge deflection by using the opposed bridge deflection remote monitoring system comprises the following steps:
s1, arranging the monitoring system on the bridge, opening a stop valve, closing all second exhaust valves, opening the first exhaust valve until the anti-freezing liquid flows out of the first exhaust valve, and closing the first exhaust valve; sequentially opening the second exhaust valve according to the sequence from far to near from the liquid storage tank until the antifreeze flows out, closing the stop valve, wherein the first liquid storage pipe is in a closed state, the second liquid storage pipe is in a communicated state, and the system enters a working state;
s2, the monitoring center sends a monitoring command remotely and transmits the command to the industrial personal computer through the remote communication module, the industrial personal computer controls the data synchronization collector to collect the pressure values of the pressure sensors in the double-base-point calibration module and the deflection measurement submodule, the pressure sensors in the double-base-point calibration module are divided into an upper pressure sensor and a lower pressure sensor, the pressure value of the upper pressure sensor is set as p1tThe pressure value of the lower pressure sensor is set to p2tSetting the pressure value of any pressure sensor in the deflection measurement submodule as pi，pi＝ρghi(i ═ 1, 2, 3,. n), where ρ is the antifreeze density and g is the acceleration of gravity at the measurement point;
s3, calculating the liquid level change pressure in the deflection measurement submodule of the ith measuring point at the moment t, and setting pitThe pressure data measured by the second pressure sensor in the deflection measurement submodule comprises two parts, namely the liquid level change pressure caused by the deflection of the bridge and the impact pressure generated by the vibration of the anti-freezing solution on the second pressure sensor caused by the vibration of the bridge when the vehicle passes through the bridge, and is recorded as p'it(ii) a The pressure measured by the first pressure sensor in the deflection measurement submodule only contains the vibration of the bridge caused by the vehicle passing through the bridge, so that the vibration of the antifreeze generates impact pressure on the first pressure sensor, and the impact pressure is recorded as p ″it；
S4, measuring pressure value p ″' of the first pressure sensoritAnd (i is 3, 4, 5.. n), carrying out envelope method processing, removing a trend term of sudden pressure increase and gradual pressure decrease caused by closing the stop valve, and obtaining pressure data, which is recorded as p, of the first pressure sensor in each deflection measuring submodule after correction1〃itBecause the first liquid storage pipe and the second liquid storage pipe are the same in size, shape and structure, the signal p of pressure change caused by the change of bridge deflectionit＝p′it-p1〃it，(i＝3，4，5...n)；
S5, calculating the height difference between the ith measuring point and the liquid level of the liquid storage tank at the time t, and setting the height difference as hit，
S6, calculating a bridge deflection value of the ith measuring point at the time t, arranging an upper pressure sensor and a lower pressure sensor in a double-base-point calibration module (3), setting the vertical distance between the upper pressure sensor and the lower pressure sensor to be L, and setting the bridge deflection value to be delta hit，
In the method for remotely monitoring the deflection of the opposed bridge, in the step S4, the envelope processing method comprises the following steps:
a. find p ″)itObtaining a maximum value and a minimum value sequence from all local extreme points of the discrete pressure data;
b. respectively carrying out segmented cubic spline difference fitting on the maximum value sequence and the minimum value sequence to obtain an upper envelope value and a lower envelope value;
c. calculating the mean value of the upper envelope and the lower envelope;
d. subtracting the average value of the corresponding upper envelope and the lower envelope from the discrete pressure data obtained in the step a to obtain the pressure data p of the first pressure sensor in each deflection measurement submodule after correction1〃it。
The monitoring system of the invention adopts the communicating pipe to communicate the liquid storage tank, the double-base-point calibration module and the deflection measurement submodule, and respectively collects the pressure values of the corresponding pressure sensors of the double-base-point calibration module and the deflection measurement submodule through the data synchronization collector, the number of the deflection measurement submodules is set according to the length of the bridge, the industrial personal computer monitors the deflection value of each measuring point in real time according to a preset method and transmits the deflection value to the remote monitoring system through the remote communication module, the structure is simpler, and the system cost is reduced; the deflection measurement submodule adopts a first liquid storage pipe and a second liquid storage pipe which are arranged oppositely, and the sizes and the shapes of the first liquid storage pipe and the second liquid storage pipe are the same, so that the influence of impact pressure generated by liquid level vibration on bridge deflection measurement can be effectively eliminated; the communication pipe interface adopts a variable-diameter interface and a damping film is added at a small-caliber position, so that the rapid flow of the anti-freezing liquid caused by the vibration of the bridge can be effectively weakened, the quality of the anti-freezing liquid in the two opposite liquid storage pipes is ensured to be equal, and the measurement precision is improved; by adopting a double-base-point calibration method, the interference of the vibration change of the liquid level of the liquid storage tank can be effectively solved, and the measurement precision is improved; the antifreeze liquid is used for replacing water in the traditional communicating pipe as the filling liquid, has the advantages of low temperature resistance, difficult volatilization, difficult deterioration and the like, and has strong environmental adaptability; the modern network communication technology is adopted, the automation degree is high, and the remote online monitoring of the bridge deflection is realized; and the deflection measurement submodule is adopted, and the deflection measurement submodule can be increased or decreased according to the length of the bridge, so that the system has wide adaptability.
The invention relates to a bridge deflection monitoring method, which comprises the steps of collecting pressure values of pressure sensors of each measuring point and a double-base-point calibration module in real time through a data synchronous collector, testing the pressure values of a deflection measurement submodule in two parts, namely pressure in a first closed liquid storage pipe, wherein the pressure is generated on the first pressure sensor by vibration of anti-freezing liquid caused by bridge vibration, carrying out Incore processing on the pressure, discharging a trend item that the pressure is suddenly increased and then gradually reduced due to closing of a stop valve, and total pressure in a second liquid storage pipe, wherein the total pressure comprises liquid level change pressure caused by bridge deflection and impact pressure generated on the second pressure sensor by vibration of the anti-freezing liquid caused by bridge vibration of a vehicle passing through a bridge, obtaining liquid level change pressure caused by bridge deflection of an ith measuring point at a certain moment, and combining the height between the ith measuring point at the certain moment and the liquid level of the liquid storage tank and the vertical distance between two pressure sensors in the double-base-point calibration module And calculating the distance L to obtain the bridge deflection value of the ith measuring point, so that the measuring precision is improved.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention;
FIG. 2 is a schematic structural diagram of a deflection measuring submodule;
FIG. 3 is a graph comparing a deflection change signal processed by the method of the present invention with a deflection change signal accurately measured by a laser displacement sensor;
FIG. 4 is an error graph generated by a deflection change signal and an accurate signal obtained by the processing of the present invention;
FIG. 5 is a signal comparison graph of deflection change signal and accurate signal obtained without processing;
FIG. 6 is an error graph of the deflection change signal and the accurate signal without processing.
In the figure: 1. a liquid storage tank; 1-1, air holes; 2. an antifreeze; 3. a double-base-point calibration module; 4. a communicating pipe; 4-1, a first exhaust valve; 5. a deflection measuring submodule; 5-1, sealing cover; 5-2, a trachea interface; 6. a data bus; 7. a data synchronization acquisition device; 8. an industrial personal computer; 9. a remote communication module; 10. a first pressure sensor; 11. a stationary washer; 12. fastening screws; 13. the device comprises a first liquid storage pipe, a first pressure sensor, a second pressure sensor, a first exhaust valve, a second exhaust valve, a first stop valve, a second exhaust valve, a second liquid storage pipe and a second exhaust valve, wherein the first liquid storage pipe 14, the stop valve 15, the second exhaust valve 16, the second liquid storage pipe 17; 18. an air tube; 19. a connecting pipe interface; 20. a damping membrane.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.
Referring to fig. 1-2, the invention discloses an opposed bridge deflection remote monitoring system, which comprises a liquid storage tank 1, a communicating pipe 4, a double-base-point calibration module 3, a deflection measurement submodule 5, a data bus 6, a data synchronization collector 7, an industrial personal computer 8 and a remote communication module 9, wherein the liquid storage tank 1 and the double-base-point calibration module 3 are fixedly arranged on a bridge pier, the deflection measurement submodule 5 is provided with i, i is 1-N, the number of N is determined by the number of measuring points required during field installation, the liquid storage tank 1 and the double-base-point calibration module 3 are uniformly arranged on a single-span bridge on a bridge floor, the lower surface of the bridge or the inside of a bridge box body according to the principle of 1/2 span, 1/4 span and 3/4 span, the communicating pipe 4 comprises a vertical section and a horizontal section which are communicated with each other, the liquid storage tank 1 and the double-base-point calibration module 3 are arranged on the vertical section of, the horizontal section of the communicating pipe 4 is arranged along the length direction of the bridge and is communicated with each deflection measuring submodule 5, and the tail end of the horizontal section is provided with a first exhaust valve 4-1 for exhausting air in the pipeline and ensuring that the antifreeze solution 2 is filled in the whole pipeline; the double-base-point calibration module 3, the deflection measurement submodule 5, the data synchronization collector 7, the industrial personal computer 8 and the remote communication module 9 are sequentially connected through a data bus 6;
the deflection measurement submodule 5 comprises an internal measurement device, the internal measurement device comprises a stop valve 14, an impact pressure measurement module and a total pressure measurement module, the impact pressure measurement module and the total pressure measurement module are identical in structure and are communicated together through the stop valve 14, the impact pressure measurement module comprises a first liquid storage pipe 13 and a first pressure sensor 10, the total pressure measurement module comprises a second liquid storage pipe 16 and a second pressure sensor 17, the first liquid storage pipe 13 and the second liquid storage pipe 16 are respectively arranged at two ends of the stop valve 14 and are horizontally and symmetrically arranged, the first liquid storage pipe and the second liquid storage pipe are identical in size, shape and structure, the first liquid storage pipe 13 is positioned at the left end, when the stop valve 14 is closed, the first liquid storage pipe 13 is a closed cavity, a second exhaust valve 15 is arranged in the middle of the first liquid storage pipe 13 to ensure that the inner cavity of the first liquid storage pipe 13 is filled with antifreeze liquid 2, the second liquid storage pipe 16 is a communicating cavity and is connected with the horizontal section of the communicating pipe 4 through a communicating pipe interface 19, the communicating pipe interface 19 is a reducing interface, the inner diameter of the upper end of the communicating pipe interface is large, the inner diameter of the lower end of the communicating pipe interface is small, and a damping film 20 is arranged at the position of the small inner diameter of the lower end of the communicating pipe interface, so that the liquid in the communicating cavity of the second liquid storage pipe 16 is prevented from flowing during vibration, and the quality of the anti-freezing liquid in the first liquid storage pipe 13 and the second; first liquid reserve pipe 13 and the 16 outer ends of second liquid reserve pipe set up first pressure sensor 10 and second pressure sensor 17 respectively, and first pressure sensor 10 and second pressure sensor 17 are used for detecting the fluid pressure in first liquid reserve pipe 13 and the second liquid reserve pipe 16 respectively, communicating pipe interface 19 with second pressure sensor 17's distance is 1cm for the data that second pressure sensor 17 measured are more accurate.
The double-base-point calibration module 3 comprises an upper pressure sensor and a lower pressure sensor, signal ends of the upper pressure sensor and the lower pressure sensor are communicated with a data synchronization collector 7 through a data bus 6, the vertical distance between the upper pressure sensor and the lower pressure sensor is L, and the vertical distance L is 1/2 of the range of the upper pressure sensor and the lower pressure sensor, so that good linearity is guaranteed.
The deflection measuring submodule 5 also comprises a sealing cover 5-1, wherein two ends of the sealing cover 5-1 are respectively provided with an air pipe interface 5-2 which is connected with the liquid storage tank 1 and other deflection measuring submodules 5 through air pipes 18; the liquid storage tank 1 is closed, the air holes 1-1 are formed in the upper portion of the liquid storage tank, the air holes 1-1 are communicated with the deflection measuring sub-modules 5 through air pipes 18, the liquid storage tank and the deflection measuring sub-systems are maintained in the same external measuring environment, and the liquid storage tank and the deflection measuring sub-systems are always in a balanced external pressure even when subjected to unexpected vibration, so that error interference in measurement is reduced.
In the specific application process, the monitoring system is communicated with the liquid storage tank, the double-base-point calibration module and the deflection measurement submodule through the communicating pipe, the pressure values of corresponding pressure sensors of the double-base-point calibration module and the deflection measurement submodule are respectively collected through the data synchronization collector, the number of the deflection measurement submodules is set according to the length of a bridge, the industrial personal computer monitors the deflection value of each measuring point in real time according to a preset method and transmits the deflection value to the remote monitoring system through the remote communication module, the structure is simpler, and the system cost is reduced; the deflection measurement submodule adopts a first liquid storage pipe and a second liquid storage pipe which are arranged oppositely, the sizes, the shapes and the structures of the first liquid storage pipe and the second liquid storage pipe are the same, and the influence of impact pressure generated by liquid level vibration on bridge deflection measurement can be effectively eliminated; the communication pipe interface adopts a variable-diameter interface and a damping film is added at a small-caliber position, so that the rapid flow of the anti-freezing liquid caused by the vibration of the bridge can be effectively weakened, the quality of the anti-freezing liquid in the two opposite liquid storage pipes is ensured to be equal, and the measurement precision is improved; by adopting a double-base-point calibration method, the interference of the vibration change of the liquid level of the liquid storage tank can be effectively solved, and the measurement precision is improved; the antifreeze liquid is used for replacing water in the traditional communicating pipe as the filling liquid, has the advantages of low temperature resistance, difficult volatilization, difficult deterioration and the like, and has strong environmental adaptability; the modern network communication technology is adopted, the automation degree is high, and the remote online monitoring of the bridge deflection is realized; and the deflection measurement submodule is adopted, and the deflection measurement submodule can be increased or decreased according to the length of the bridge, so that the system has wide adaptability.
The invention also discloses a method for realizing the remote monitoring of the bridge deflection by using the monitoring system, which comprises the following specific steps:
s1, arranging the monitoring system on the bridge, opening a stop valve 14, closing all second exhaust valves 19, opening the first exhaust valve 4-1 until the anti-freezing liquid flows out of the first exhaust valve 4-1, and closing the first exhaust valve 4-1; sequentially opening the second exhaust valve 15 from far to near from the liquid storage tank 1 until the antifreeze flows out, closing the stop valve 14, closing the first liquid storage pipe 13, communicating the second liquid storage pipe 16, and enabling the system to enter a working state;
s2, the monitoring center sends the monitoring instruction remotely through the remote communicationThe signal module 9 is transmitted to the industrial personal computer 8, the industrial personal computer 8 controls the data synchronous collector 7 to collect the pressure values of the pressure sensors in the double-base-point calibration module 3 and the deflection measurement submodule 5, the pressure sensors in the double-base-point calibration module 3 are divided into an upper pressure sensor and a lower pressure sensor, and the pressure value of the upper pressure sensor is set as p1tThe pressure value of the lower pressure sensor is set to p2tThe pressure value of any pressure sensor in the deflection measuring submodule 5 is set as pi，pi＝ρghi(i ═ 1, 2, 3,. n), where ρ is the antifreeze density and g is the acceleration of gravity at the measurement point;
s3, calculating the liquid level change pressure in the deflection measuring submodule 5 of the ith measuring point at the moment t, and setting pitIn order to obtain the liquid level change pressure caused by the bridge deflection at the ith measuring point at the time t, the pressure data measured by the second pressure sensor 17 in the deflection measuring submodule 5 comprises two parts, namely the liquid level change pressure caused by the bridge deflection and the impact pressure generated by the vibration of the anti-freezing solution on the second pressure sensor 17 caused by the bridge vibration when the vehicle passes through the bridge, which are recorded as p'it(ii) a The pressure measured by the first pressure sensor 10 in the deflection measuring submodule 5 only includes the vibration of the bridge caused by the vehicle passing through the bridge, so that the vibration of the antifreeze generates impact pressure on the first pressure sensor 10, which is recorded as p ″it；
S4, pressure value p' measured by the first pressure sensor 10itAnd (i ═ 3, 4, 5.. n) performing an envelope method treatment, wherein the method comprises the following steps:
a. find p ″)itObtaining a maximum value and a minimum value sequence from all local extreme points of the discrete pressure data;
b. respectively carrying out segmented cubic spline difference fitting on the maximum value sequence and the minimum value sequence to obtain an upper envelope value and a lower envelope value;
c. calculating the mean value of the upper envelope and the lower envelope;
d. subtracting the average value of the corresponding upper envelope and the lower envelope from the discrete pressure data obtained in the step a to obtain the corrected pressure data of the first pressure sensor 10 in each deflection measurement submodule;
danguan (in the open)When the stop valve 14 is closed, the first liquid storage pipe 13 is in a sealed state, the initial pressure of the liquid in the first liquid storage pipe 13 may fluctuate at a new equilibrium position instead of the pressure before sealing due to the different forms of the stop valve 14, and the equilibrium position is a fluctuation value instead of a constant value due to the sealing performance of the valve body, so that the trend term of pressure change needs to be removed by an envelope method during calculation. Processing the pressure data measured by the first pressure sensor 10 by adopting a Baulou method, removing a trend item that the pressure is suddenly increased and then gradually reduced due to the closing of the stop valve 14, and obtaining the corrected pressure data of the first pressure sensor 10 in each deflection measuring submodule, and marking the corrected pressure data as p1〃itBecause the first liquid storage pipe and the second liquid storage pipe are the same in size, shape and structure, the signal p of pressure change caused by the change of bridge deflectionit＝p′it-p1〃it，(i＝3，4，5...n)；
S5, calculating the height difference between the ith measuring point and the liquid level of the liquid storage tank at the time t, and setting the height difference as hit，
S6, calculating a bridge deflection value of the ith measuring point at the time t, arranging an upper pressure sensor and a lower pressure sensor in a double-base-point calibration module (3), setting the vertical distance between the upper pressure sensor and the lower pressure sensor to be L, and setting the bridge deflection value to be delta hit，
In the specific monitoring process: and a deflection measurement submodule 5 is arranged at each measuring point of the bridge and is connected with the liquid storage tank 1 and the double-base-point calibration module 3 through a communicating pipe 4 arranged on the bridge, and the whole communicating pipe 4 is filled with the antifreezing solution 2. After the monitoring system is installed, the stop valve 14 is opened, all the second exhaust valves 19 are closed, the first exhaust valve 4-1 is opened until the antifreeze flows out of the first exhaust valve 4-1, the air in the communicating pipe 4 is exhausted, and the first exhaust valve 4-1 is closed;sequentially opening each second exhaust valve 15 according to the sequence from far to near from the liquid storage tank 1 until the antifreeze liquid flows out, wherein the deflection measurement submodule 5 further comprises a sealing cover 5-1, the two ends of the sealing cover 5-1 are respectively provided with an air pipe interface 5-2, the liquid storage tank is sealed, the upper part of the liquid storage tank is provided with an air hole, and the air pipe interfaces 5-2 on the deflection measurement submodule 5 are connected with an air pipe 18, so that the pressure of the inner measuring device is consistent with the pressure in the liquid storage tank; closing the stop valve 14, wherein the first liquid storage pipe 13 is in a sealed state, and when the vehicle passes through the time t, the pressure measured by the first pressure sensor 10 arranged outside the first liquid storage pipe 13 is the bridge vibration caused by the vehicle passing through the bridge, so that the vibration of the antifreeze generates impact pressure on the first pressure sensor 10, which is denoted as p ″itAnd is processed by the inclusion method to remove a trend term, denoted as p, of sudden pressure increase and then gradual pressure decrease caused by closing the stop valve 141〃it(ii) a The pressure value measured by the second pressure sensor 17 includes two parts, namely liquid level change pressure caused by bridge deflection and impact pressure generated by vibration of the anti-freezing liquid to the second pressure sensor 17 caused by bridge vibration of a vehicle passing through the bridge, and is recorded as p'it(ii) a And the pressure values measured by the upper pressure sensor and the lower pressure sensor of the double-base-point calibration module 3 are p respectively1t、p2t(ii) a The deflection measurement submodule 5 transmits data to an industrial personal computer 8 through a data bus 6, and the industrial personal computer 8 calculates to obtain the real deflection change data of the bridge through the following algorithm:
pi＝ρghi(i＝1，2，3，...n)；
pit＝p′it-p1〃it，(i＝3，4，5，...n)；
wherein p isiIs the ith pressure sensorMeasuring a pressure value; rho is the density of the antifreeze solution 2; g is the gravitational acceleration at the survey point; p is a radical ofitThe pressure of the liquid level change of the ith measuring point at the moment t caused by the deflection of the bridge; p'itThe pressure of the liquid level change of the ith measuring point at the time t caused by the deflection of the bridge and the vibration of the bridge caused by the passing of a vehicle through the bridge are two parts, so that the vibration of the antifreeze liquid generates impact pressure on the pressure sensor; p is a radical of1″itThe pressure is the pressure after the ith measuring point at the time t is corrected by the Incore method because the vehicle passes through the bridge to cause the vibration of the bridge, and further the vibration of the antifreeze liquid is used for carrying out the Incore method on the impact pressure generated by the pressure sensor; h isitThe height from the ith measuring point to the liquid level of the liquid storage tank at the moment t; p is a radical of1t，p2tThe pressure values measured by two pressure sensors in the double-base-point pressure calibration module 3 at the time t (marked as a reference point 1 and a reference point 2, wherein the reference point 1 is positioned at a position L right above the reference point 2); Δ hitAnd obtaining the bridge deflection value of the ith deflection measurement submodule 5 at the time t.
The method includes the steps that pressure values of pressure sensors of each measuring point and a double-base-point calibration module 3 are collected in real time through a data synchronization collector 7, the pressure value of each pressure sensor and liquid level change pressure of an ith measuring point at a certain moment caused by bridge deflection are calculated step by step, the height between the ith measuring point at a certain moment and the liquid level of a liquid storage tank and the vertical distance L between two pressure sensors in the double-base-point calibration module are combined, the bridge deflection value of the ith measuring point is obtained through calculation, and measuring accuracy is improved.
Comparing the deflection change signal obtained by the processing of the method with the deflection change signal accurately measured by a laser displacement sensor, as shown in FIG. 3, and obtaining an error graph of the deflection change signal obtained by the processing of the invention and the accurate signal, as shown in FIG. 4; the deflection change signal obtained without the inventive treatment is compared with the signal of the accurate signal, as shown in fig. 5, and an error map of the deflection change signal obtained without the inventive treatment and the accurate signal is obtained, as shown in fig. 6. The deflection change value error of the bridge processed and measured by the method can be greatly reduced, and the deflection change value can be accurately measured.
Claims (5)
1. A method for remotely monitoring bridge deflection is characterized by comprising the following steps: the monitoring method utilizes an opposed bridge deflection remote monitoring system to realize remote monitoring, the opposed bridge deflection remote monitoring system comprises a liquid storage tank (1), a communicating pipe (4), a double-base-point calibration module (3), a deflection measuring submodule (5), a data bus (6), a data synchronous collector (7), an industrial personal computer (8) and a remote communication module (9), the liquid storage tank (1) and the double-base-point calibration module (3) are fixedly arranged on a pier, the deflection measuring submodule (5) is provided with i, i is 1-N, the number of N is determined by the number of measuring points required in field installation, the deflection measuring submodule is uniformly arranged on a bridge floor, the lower surface of a bridge or the inside of a bridge box body at intervals, the communicating pipe (4) comprises a vertical section and a horizontal section which are communicated with each other, and the liquid storage tank (1) and the double-base-point calibration module (3) are arranged on the vertical section of the communicating pipe (4, the horizontal section of the communicating pipe (4) is communicated with each deflection measuring submodule (5); the double-base-point calibration module (3), the deflection measurement submodule (5), the data synchronization collector (7), the industrial personal computer (8) and the remote communication module (9) are sequentially connected through a data bus (6);
the deflection measuring submodule (5) comprises an internal measuring device, the internal measuring device is provided with a total pressure measuring module, the total pressure measuring module comprises a second liquid storage pipe (16) and a second pressure sensor (17), and the second liquid storage pipe (16) is communicated with the horizontal section of the communicating pipe (4) through a communicating pipe interface (19) arranged in the middle of the second liquid storage pipe; the second pressure sensor (17) is arranged in the second liquid storage pipe (16) and is used for detecting the liquid pressure in the second liquid storage pipe (16);
the double-base-point calibration module (3) comprises an upper pressure sensor and a lower pressure sensor, the signal ends of the upper pressure sensor and the lower pressure sensor are communicated with a data synchronization collector (7) through a data bus (6), the vertical distance between the upper pressure sensor and the lower pressure sensor is L, and the vertical distance L is 1/2 of the measuring range of the upper pressure sensor and the lower pressure sensor;
an impact pressure measuring module is additionally arranged, the impact pressure measuring module and the total pressure measuring module have the same structure and are communicated together through a stop valve (14); the impact pressure measuring module comprises a first liquid storage pipe (13) and a first pressure sensor (10), the first liquid storage pipe (13) and a second liquid storage pipe (16) are respectively installed at two ends of a stop valve (14) and are horizontally and symmetrically arranged, the first liquid storage pipe (13) and the second liquid storage pipe (16) are identical in size, shape and structure, the first liquid storage pipe (13) is located at the left end, and the second liquid storage pipe (16) is located at the right end; when the stop valve (14) is closed, the first liquid storage pipe (13) is a closed cavity, and the second liquid storage pipe (16) is a communicated cavity; the left end of the first liquid storage pipe (13) is provided with a first pressure sensor (10), and the first pressure sensor (10) is used for detecting the liquid pressure of the first liquid storage pipe (13).
The height of the liquid storage tank (1) at the top end of the vertical section of the communicating pipe (4) is 20-40cm higher than that of the horizontal section, the extending direction of the horizontal section is the same as the length direction of the bridge, and the tail end of the horizontal section is provided with a first exhaust valve (4-1); a second exhaust valve (15) is arranged in the middle of the first liquid storage pipe (13) and used for detecting that the first liquid storage pipe (13) is filled with the antifreeze (2);
the monitoring method comprises the following steps:
s1, mounting deflection measurement sub-modules (5) at each measuring point of the bridge, connecting the deflection measurement sub-modules with a liquid storage tank (1) and a double-base-point calibration module (3) through communicating pipes (4) arranged on the bridge, sequentially connecting the double-base-point calibration module (3), the deflection measurement sub-modules (5), a data synchronization collector (7), an industrial personal computer (8) and a remote communication module (9) through a data bus (6), opening a stop valve (14), closing all second exhaust valves (15), opening a first exhaust valve (4-1) until antifreeze (2) flows out of the first exhaust valve (4-1), and closing the first exhaust valve (4-1); sequentially opening the second exhaust valves (15) according to the sequence from far to near from the liquid storage tank (1) until the antifreeze flows out, closing the stop valve (14), wherein the first liquid storage pipe (13) is in a closed state, the second liquid storage pipe (16) is in a communicated state, and the system enters a working state;
s2, the monitoring center sends a monitoring command remotely and transmits the monitoring command to the industrial personal computer (8) through the remote communication module (9)) The industrial personal computer (8) controls the data synchronous collector (7) to collect pressure values of pressure sensors in the double-base-point calibration module (3) and the deflection measurement submodule (5), the pressure sensors in the double-base-point calibration module (3) are divided into an upper pressure sensor and a lower pressure sensor, and the pressure value of the upper pressure sensor is set as p1tThe pressure value of the lower pressure sensor is set to p2tThe pressure value of any pressure sensor in the deflection measurement submodule (5) is set as pi，pi＝ρghi(i ═ 1, 2, 3,. and n), where ρ is the antifreeze density and g is the gravitational acceleration at the measurement point;
s3, calculating the liquid level change pressure in the deflection measuring submodule (5) of the ith measuring point at the moment t, and setting pitThe pressure data measured by the second pressure sensor (17) in the deflection measurement submodule (5) comprises two parts, namely the liquid level change pressure caused by the deflection of the bridge and the impact pressure generated by the vibration of the anti-freezing solution on the second pressure sensor (17) caused by the vibration of the bridge when the vehicle passes through the bridge, which are recorded as p'it(ii) a The pressure measured by the first pressure sensor (10) in the deflection measuring submodule (5) only comprises the vibration of a bridge caused by the fact that a vehicle passes through the bridge, and further the vibration of the antifreeze generates impact pressure on the first pressure sensor (10), which is recorded as p ″it；
S4, measuring the pressure value p ″' of the first pressure sensor (10)itAnd (i is 3, 4, 5, n), carrying out envelope method processing, removing a trend term of sudden pressure increase and gradual pressure decrease caused by closing the stop valve (14), and obtaining pressure data, noted as p, of the first pressure sensor (10) in each deflection measuring submodule after correction1〃itBecause the first liquid storage pipe and the second liquid storage pipe are the same in size, shape and structure, the signal p of pressure change caused by the change of bridge deflectionit＝p′it-p1〃it，(i＝3，4，5，...，n)；
S5, calculating the height difference between the ith measuring point and the liquid level of the liquid storage tank at the time t, and setting the height difference as hit，
S6, calculating a bridge deflection value of the ith measuring point at the time t, arranging an upper pressure sensor and a lower pressure sensor in a double-base-point calibration module (3), setting the vertical distance between the upper pressure sensor and the lower pressure sensor to be L, and setting the bridge deflection value to be delta hit，
In step S4, the enveloping processing includes the following steps:
a. find p ″)itObtaining a maximum value and a minimum value sequence from all local extreme points of the discrete pressure data;
b. respectively carrying out segmented cubic spline difference fitting on the maximum value sequence and the minimum value sequence to obtain an upper envelope value and a lower envelope value;
c. calculating the mean value of the upper envelope and the lower envelope;
d. subtracting the average value of the corresponding upper envelope and the lower envelope from the discrete pressure data obtained in the step a to obtain the corrected pressure data p of the first pressure sensor (10) in each deflection measurement submodule1〃it。
2. The method for remotely monitoring the deflection of the bridge according to claim 1, wherein: the communicating pipe joint (19) is a reducing communicating pipe joint, the inner diameter of the upper end of the communicating pipe joint is large, and the inner diameter of the lower end of the communicating pipe joint is small; a damping film (20) is arranged at the small inner diameter position of the lower end of the communication pipe connector (19), and the distance between the communication pipe connector (19) and the second pressure sensor (17) is 1 cm.
3. The method for remotely monitoring the deflection of the bridge according to claim 2, wherein: the deflection measuring submodule (5) further comprises a sealing cover (5-1), wherein air pipe interfaces (5-2) are respectively arranged at two ends of the sealing cover (5-1) and are communicated with the liquid storage tank (1) and other deflection measuring submodules (5) through air pipes (18).
4. A method of remotely monitoring bridge deflection as claimed in claim 3, wherein: the liquid storage tank (1) is closed, the upper part of the liquid storage tank is provided with air holes (1-1), and the air holes (1-1) are connected with the deflection measuring submodules (5) through air pipes (18).
5. The method of remotely monitoring bridge deflection of claim 4, wherein: first liquid reserve pipe (13) and second liquid reserve pipe (16) are the glossy aluminium alloy pipe of hollow inner wall, first pressure sensor (10) and second pressure sensor (17) are respectively through fastening screw (12) fixed mounting in first liquid reserve pipe (13) and second liquid reserve pipe (16) outer end, all be provided with between first pressure sensor (10) and first liquid reserve pipe (13) and between second pressure sensor (17) and second liquid reserve pipe (16) retaining washer (11).
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| CN108829998A (en) * | 2018-06-25 | 2018-11-16 | 石家庄铁道大学 | A kind of detection method of deflection of bridge span, detection device and terminal device |
| CN109186531A (en) * | 2018-09-26 | 2019-01-11 | 招商局重工(深圳)有限公司 | A kind of concentration water tank type deflection metrology system |
| CN109916582B (en) * | 2019-03-28 | 2020-02-18 | 华南理工大学 | Automatic deflection measuring device and method |
| CN110068366A (en) * | 2019-05-22 | 2019-07-30 | 江苏东交工程检测股份有限公司 | Device and method for monitoring road surface bridge tunnel internal motion state |
| CN110608862A (en) * | 2019-06-05 | 2019-12-24 | 广东汇涛工程科技有限公司 | Method for measuring dynamic mean deflection of bridge through tilt angle sensor |
| CN111535152B (en) * | 2020-05-01 | 2021-05-14 | 安徽建筑大学 | Beam structure with elastic rotation restraint and vertical elastic support |
| CN111537169B (en) * | 2020-05-11 | 2021-09-28 | 中国建筑第七工程局有限公司 | Movable bridge deflection detector |
| CN112747877B (en) * | 2020-10-16 | 2022-03-29 | 上海交通大学 | Non-contact bridge structure performance and safety rapid test and evaluation system and method |
| CN112284325A (en) * | 2020-11-09 | 2021-01-29 | 水利部交通运输部国家能源局南京水利科学研究院 | Dynamic testing method for ship-receiving chamber deflection of ship lift |
| CN112815912B (en) * | 2020-12-31 | 2022-04-29 | 中冶建筑研究总院有限公司 | Device and method for detecting vertical displacement of bridge |
| CN113701968B (en) * | 2021-07-12 | 2023-10-13 | 北京建筑大学 | Bridge dynamic deflection monitoring system |
| CN115096529B (en) * | 2022-07-26 | 2023-08-04 | 大连理工大学 | Bridge dynamic deflection distributed measurement device and measurement method |
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| CN103292774B (en) * | 2013-05-31 | 2016-04-13 | 广州大学 | A kind of dynamic deflection metrology method of bridge |
| CN203551236U (en) * | 2013-07-26 | 2014-04-16 | 重庆亚派桥梁工程质量检测有限公司 | Vacuum communication pipe bridge deflection monitoring system based on silicone oil |
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