Modular bridge expansion joint multi-parameter monitoring device and method

Abstract

The multi-parameter monitoring device and method for the expansion joint of a bridge belong to the technical field of bridge health monitoring. The device is a multi-sensor fusion system, comprising displacement, height, three-axis vibration, ultrasonic guided wave transmitting and receiving probes, and water leakage cable sensors. The method completes multi-sensor data processing in the monitoring device host to obtain the six-degree-of-freedom motion, joint width, bearing capacity, three-axis vibration amplitude, mid-beam three-axis vibration frequency and amplitude, water intrusion original data, and disease alarm of mechanical interference, vehicle overload, rubber support falling, mid-beam fracture, and damaged sealing rubber strip of the bridge expansion joint. The monitoring device host sends the above data and alarm information to the cloud platform through the network to complete data aggregation and real-time display, and prompts the operation state and potential diseases of the bridge expansion joint. The present application has the characteristics of comprehensive monitoring parameters, accurate analysis of potential diseases of the bridge expansion joint, prompt of potential risks of the bridge, and strong promotion to other types of expansion joints.

Description

Technical Field

[0001] This invention belongs to the field of bridge health monitoring technology, and specifically relates to a multi-parameter monitoring device and method for modular bridge expansion joints. Background Technology

[0002] Bridges are a vital component of transportation. Currently, my country has nearly 800,000 highway bridges and over 200,000 railway bridges, with a total length exceeding 50,000 kilometers. At the same time, the number of in-service bridges entering their maintenance period in my country's highway network is steadily increasing, with over 100,000 bridges classified as dangerous. Approximately 40% of the in-service bridges in my country's highway network have been in service for over 20 years, and 30% of these are classified as Class III or IV bridges with existing defects. The number of bridges entering their maintenance period is steadily rising.

[0003] Throughout the entire life cycle of a bridge, factors such as bridge load, earthquakes, and aging of internal components can all cause varying degrees of damage to bridge expansion joints and affect their performance. Traditional methods such as manual visual inspection can only make a rough judgment on whether damage has occurred through appearance. This method relies mainly on human experience and mainly involves visual inspection and measurement. Unless the bridge expansion joint has been obviously damaged, it is difficult to detect problems and provide early warnings. It lacks accurate and scientific data support, cannot establish accurate analytical models and corresponding relationships, and cannot reflect the true health status of the bridge expansion joint, thus having significant limitations.

[0004] Currently, the main problems facing bridge expansion joint monitoring technology can be summarized as follows:

[0005] 1. Insufficient monitoring parameters. Current monitoring technologies and mass-produced products only monitor single parameters and single problems. However, the safety monitoring of bridge expansion joints involves a comprehensive issue of stress, deformation, fatigue, vibration, temperature, and environment. Existing monitoring methods do not design monitoring devices from the perspective of needs, resulting in insufficient monitoring parameters and an inability to fully reflect the operating status of bridge expansion joints.

[0006] 2. Outdated data collection and analysis methods and low level of intelligence. Emerging wireless communication technologies have not been applied to monitoring technologies. Wired and local area transmission technologies cannot cover the significant needs of monitoring major bridges, resulting in data fragmentation and poor data collection capabilities. In addition, edge computing, cloud computing, and artificial intelligence technologies have not been widely applied, resulting in weak analytical capabilities for collected data and inaccurate results for safety monitoring, accident early warning, and lifespan analysis.

[0007] 3. Monitoring technologies and methods are outdated and have low accuracy. Monitoring technologies are still limited to the superficial measurement of parameters such as strain, bearing capacity, and deformation. They are insufficient for monitoring potential defects such as vibration, fatigue, cracks, wear, and leakage. New methods and technologies from other fields have not yet been applied in the field of bridge expansion joint monitoring. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing technologies in monitoring bridge expansion joints, such as insufficient monitoring methods, single monitoring parameters, and the inability to construct a comprehensive monitoring system. This invention provides a multi-parameter monitoring device and method suitable for bridge expansion joints. The invention employs intelligent rubber bearings, displacement sensors, height sensors, triaxial vibration sensors, ultrasonic guided wave transmitters and receivers, and leakage cable sensors to construct a multi-parameter monitoring device for bridge expansion joints. By combining the measurement data from the displacement and height sensors with their spatial installation positions, it monitors the six degrees of freedom motion, joint width, and mechanical interference of the expansion joint. By combining the force data from the intelligent rubber bearings, it monitors vehicle overloading and rubber bearing detachment. By combining the measurement data from the triaxial vibration sensor with vibration spectrum analysis or ultrasonic echo signals, it monitors beam fracture. By combining the resistance changes from the leakage cable sensor, it monitors damage to the sealing rubber strip. The main unit of the multi-parameter monitoring device can send the above raw data and alarm information to a cloud platform via wired or wireless networks for data aggregation and real-time display, indicating the operating status and potential defects of the monitored modular bridge expansion joints.

[0009] The technical solution of this invention is:

[0010] A multi-parameter monitoring device for modular bridge expansion joints includes: a side beam of the monitored modular bridge expansion joint, an opposite side beam, a middle beam of the monitored modular bridge expansion joint, a middle beam at the center of symmetry of the monitored modular bridge expansion joint, a crossbeam of the monitored modular bridge expansion joint, an intelligent rubber bearing of the monitored modular bridge expansion joint, displacement sensors 1, 2, 3, 4, and 5, height sensors 1, 2, 3, and 4, triaxial vibration sensors (installation type 1 and 2), an ultrasonic guided wave transmitter and receiver probe, and a leakage cable sensor. The device comprises two sensors: a displacement sensor 1 installed near the center of the opposite side beam; displacement sensors 2 and 3 installed on the opposite side beam and symmetrically arranged at a distance D1 from displacement sensor 1; displacement sensors 1, 2, and 3 measuring the displacement from their respective installation positions to the center of the opposite side beam; and displacement sensors 4 and 5 installed on the opposite side beam, respectively near the two ends of the perpendicular lane of the monitored modular bridge expansion joint at a distance D2; displacement sensors 4 and 5 measuring the vertical displacement from their respective installation positions to the side beam. A height sensor 1 is installed on the side beam and connected to... Near the center, height sensor two is installed on the opposite side beam, close to the center. Height sensors three and four are installed on the central beam at the center of symmetry of the modular bridge expansion joint, respectively close to the two ends of the perpendicular lane of the monitored modular bridge expansion joint, at a distance of D3. Height sensors one, two, three, and four are used to measure the height between their installation positions and a fixed height reference point. The triaxial vibration sensor installation type one is installed on the support structure below the intelligent rubber bearing, connected to the central beam of the monitored modular bridge expansion joint. The triaxial vibration sensor installation type two and ultrasonic guide... The wave transmitting and receiving probe is installed on the central beam of the modular bridge expansion joint being monitored. The leakage cable sensor is installed in a serpentine pattern below the modular bridge expansion joint being monitored, with a distribution range as large as possible. The intelligent rubber bearing, displacement sensor 1, displacement sensor 2, displacement sensor 3, displacement sensor 4, displacement sensor 5, height sensor 1, height sensor 2, height sensor 3, height sensor 4, triaxial vibration sensor installation type 1, triaxial vibration sensor installation type 2, ultrasonic guided wave transmitting and receiving probe, and leakage cable sensor are respectively connected to the main unit of the multi-parameter monitoring device of the modular bridge expansion joint through cables to form signal and power supply paths.

[0011] The modular bridge expansion joint includes multiple monitored modular bridge expansion joints with central beams and intelligent rubber bearings. Multiple triaxial vibration sensors of type II and ultrasonic guided wave transmitters and receivers are installed at locations where the central beams of the monitored modular bridge expansion joints are prone to fracture. Multiple triaxial vibration sensors of type I are installed at locations where the intelligent rubber bearings are prone to detachment. The types of triaxial vibration sensor installation types I and II represent the types of sensor installation locations, respectively, installed on the support structure connected to the central beams of the monitored modular bridge expansion joints below the intelligent rubber bearings and on the central beams of the monitored modular bridge expansion joints.

[0012] The intelligent rubber bearing contains a force-sensing element that can measure the supporting force applied to it.

[0013] Among them, displacement sensor 1, displacement sensor 2, displacement sensor 3, displacement sensor 4, and displacement sensor 5 are laser displacement sensors or contact displacement sensors.

[0014] Among them, height sensor 1, height sensor 2, height sensor 3, and height sensor 4 can measure the height between the installation position and the fixed height reference point. Height sensor 1, height sensor 2, height sensor 3, and height sensor 4 are level sensors, laser displacement sensors, or contact displacement sensors. The fixed height reference point should be selected at any fixed position on the bridge.

[0015] Among them, the multi-parameter monitoring device for modular bridge expansion joints needs to select and install all or some of the following components of the monitored modular bridge expansion joints according to actual monitoring requirements: intelligent rubber bearings, displacement sensors 1, 2, 3, 4, and 5; height sensors 1, 2, 3, and 4; triaxial vibration sensors (installation type 1 and 2); ultrasonic guided wave transmitters and receivers; and leakage cable sensors.

[0016] Among them, the ultrasonic guided wave transmitter and receiver probe is used to couple ultrasonic waves into the central beam of the monitored modular bridge expansion joint at the installation location and receive ultrasonic echo signals.

[0017] When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the monitoring system should be set up according to the installation positions and functions of the displacement sensor 1, displacement sensor 2, displacement sensor 3, displacement sensor 4, displacement sensor 5, height sensor 1, height sensor 2, height sensor 3, height sensor 4, triaxial vibration sensor installation type 1, triaxial vibration sensor installation type 2, ultrasonic guided wave transmitting and receiving probe, and leakage cable sensor in the modular bridge expansion joint multi-parameter monitoring device. This system can also realize the multi-parameter monitoring function of the bridge expansion joint.

[0018] A multi-parameter monitoring method for modular bridge expansion joints is characterized by acquiring and processing measurement data from the intelligent rubber bearings, displacement sensors 1, 2, 3, 4, and 5, height sensors 1, 2, 3, and 4, triaxial vibration sensors (installation type 1 and 2), ultrasonic guided wave transmitters and receivers, and a leakage cable sensor of the monitored modular bridge expansion joint, thereby obtaining the operational status of the monitored modular bridge expansion joint. The system collects raw data on six-degree-of-freedom motion, joint width, load-bearing capacity, triaxial vibration amplitude, triaxial vibration frequency, and water intrusion. Simultaneously, the main unit of the multi-parameter monitoring device for modular bridge expansion joints further analyzes the data to obtain alarm information on defects such as mechanical interference, vehicle overloading, rubber bearing detachment, central beam fracture, and damaged sealing rubber strips during the movement of the modular bridge expansion joint. The main unit of the multi-parameter monitoring device for modular bridge expansion joints can send the above raw data and alarm information to the cloud platform via wired or wireless network to complete data aggregation and real-time display, indicating the operating status and potential defects of the monitored modular bridge expansion joint.

[0019] The relationship between the original motion data of the six degrees of freedom of the modular bridge expansion joint and the measurement results Disp1, Disp2, Disp3, Disp4, Disp5, H1, H2, H3, and H4 of the height sensor and their spatial installation positions is as follows: the linear displacement along the driving direction is Disp1, and the rotation angle is... Linear displacement perpendicular to the driving direction The corner is The vertical bridge deck linear displacement H1-H2 and the rotation angle are... The distance between displacement sensors 2 and 3 and displacement sensor 1 is D1, the distance between displacement sensors 3 and 4 is D2, and the distance between height sensors 3 and 4 is D3. After obtaining the original data of the six degrees of freedom motion of the modular bridge expansion joint, the gap width of the middle beam of the monitored modular bridge expansion joint should be calculated based on the width and number of the middle beams of the monitored modular bridge expansion joint to determine whether mechanical contact occurs between the middle beams of the monitored modular bridge expansion joint, so as to obtain the alarm information of mechanical interference in the motion of the modular bridge expansion joint. The calculation of the original data of the six degrees of freedom motion of the modular bridge expansion joint and the alarm information of mechanical interference are completed in the host of the multi-parameter monitoring device of the modular bridge expansion joint.

[0020] The load-bearing capacity measurement results of each intelligent rubber bearing of the monitored modular bridge expansion joint include the preload of the intelligent rubber bearing and the load force of the vehicle passing through the modular bridge expansion joint. When no vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing is the preload F1, and when a vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing is F3. The axle load of the vehicle passing through the modular bridge expansion joint is F3 minus F1. The preload F1 and the axle load of the vehicle can be used to determine whether each rubber bearing has a risk of falling off and to obtain overload alarm information. The preload of each intelligent rubber bearing and the load force of the vehicle passing through the modular bridge expansion joint are calculated in the main unit of the multi-parameter monitoring device of the modular bridge expansion joint, and the vehicle overload and rubber bearing falling off alarm information are obtained.

[0021] The triaxial vibration sensor has a sampling rate of no less than 200 Hz and a single sampling time of no less than 1 second. After each triaxial vibration sensor collects acceleration data once, it performs discrete Fourier transform on the data of the three measurement axes to obtain the vibration spectrum. The amplitude of the maximum amplitude frequency point of the vibration spectrum of the three measurement axes is compared. The amplitude, frequency, and vibration axis of the maximum amplitude frequency point of the measurement axis with the largest amplitude are used as the output data of each triaxial vibration sensor and transmitted to the host of the modular bridge expansion joint multi-parameter monitoring device. The host of the modular bridge expansion joint multi-parameter monitoring device compares the amplitude and frequency of each triaxial vibration sensor with the set threshold. When the amplitude of the triaxial vibration sensor is greater than the threshold, the host of the modular bridge expansion joint multi-parameter monitoring device includes the rubber bearing detachment and the middle beam fracture at the installation position of the triaxial vibration sensor in the alarm information.

[0022] When the sealing rubber strip of the modular bridge expansion joint is damaged, rainwater will come into contact with the leakage cable sensor through the sealing rubber strip. When the leakage cable sensor comes into contact with water at any point, the resistance of the leakage cable sensor will decrease. The main unit of the multi-parameter monitoring device of the modular bridge expansion joint measures the resistance of the leakage cable sensor. When the resistance of the leakage cable sensor is less than the set threshold, the sealing rubber strip damage alarm information can be obtained.

[0023] Among them, the ultrasonic guided wave transmitting and receiving probe can compare the ultrasonic echo signal of the crack-free middle beam of the monitored modular bridge expansion joint with the real-time measured ultrasonic echo signal, and evaluate the location and depth of the crack in the middle beam of the monitored modular bridge expansion joint based on the changes in the amplitude and phase of the acoustic echo signal.

[0024] When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the multi-parameter monitoring and data processing of other types of bridge expansion joints should be carried out in accordance with any of the methods described in the multi-parameter monitoring methods for modular bridge expansion joints, which can also realize the multi-parameter monitoring function of the bridge expansion joint.

[0025] The advantages of this invention are:

[0026] 1. Comprehensive monitoring parameters. This invention utilizes the fusion of multiple sensors, including intelligent rubber bearings, displacement sensors, height sensors, triaxial vibration sensors, and leakage cable sensors, to achieve high-precision monitoring of multiple raw operating parameters of bridge expansion joints, such as six degrees of freedom motion, joint width, load-bearing capacity, triaxial vibration amplitude, triaxial vibration frequency, ultrasonic guided wave signal characteristics, and water intrusion.

[0027] 2. Accurate analysis of potential defects in bridge expansion joints. This invention combines the causes and results of defects in bridge expansion joints, and conducts in-depth analysis of the raw data collected by sensors. It can obtain accurate alarm information on defects such as mechanical interference during the movement of bridge expansion joints, vehicle overloading, rubber bearing detachment, central beam fracture, and damage to sealing rubber strips.

[0028] 3. It can remotely transmit data to a cloud server and alert bridges to potential risks. The main unit of the multi-parameter monitoring device for bridge expansion joints can send the above raw data and alarm information to the cloud platform via wired or wireless networks to complete data aggregation and real-time display, remotely alerting bridge maintenance units to the precise operating status and potential defects of the monitored bridge expansion joints.

[0029] 4. Strong applicability to other types of expansion joints. Based on the basic principle of bridge expansion joints, when monitoring bridge expansion joints that are not modular, the monitoring system can be set up according to the installation positions of displacement sensors, height sensors, triaxial vibration sensors, and leakage cable sensors in the multi-parameter monitoring device for modular bridge expansion joints. Furthermore, by using the same data processing method, the multi-parameter monitoring function for other types of bridge expansion joints can also be realized. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a multi-parameter monitoring device for modular bridge expansion joints;

[0031] In the diagram: 11a. Side beam of the monitored modular bridge expansion joint; 11b. Opposite side beam; 12a. Middle beam of the monitored modular bridge expansion joint; 12b. Middle beam at the center of symmetry of the modular bridge expansion joint; 13. Cross beam of the monitored modular bridge expansion joint; 14. Intelligent rubber bearing of the monitored modular bridge expansion joint; 15. Displacement sensor one; 16. Displacement sensor two; 17. Displacement sensor three; 18. Displacement sensor four; 19. Displacement sensor five; 20. Height sensor one; 21. Height sensor two; 22. Height sensor three; 23. Height sensor four; 24. Triaxial vibration sensor installation type one; 25. Triaxial vibration sensor installation type two; 26. Ultrasonic guided wave transmitter and receiver probe; 27. Leakage cable sensor.

[0032] Figure 2 This is a schematic diagram illustrating the principle of measuring linear displacement of a bridge expansion joint in the direction of traffic.

[0033] Figure 3 This is a schematic diagram illustrating the principle of measuring the angle of rotation of a bridge expansion joint along the direction of traffic.

[0034] Figure 4 This is a schematic diagram illustrating the principle of measuring the angle of rotation of a bridge expansion joint in the direction of traffic.

[0035] Figure 5 This is a schematic diagram illustrating the principle of measuring the vertical bridge deck rotation angle of a bridge expansion joint. Detailed Implementation

[0036] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings:

[0037] A multi-parameter monitoring device for a modular bridge expansion joint includes a side beam 11a of the monitored modular bridge expansion joint, an opposite side beam 11b, a middle beam 12a of the monitored modular bridge expansion joint, a middle beam 12b at the center of symmetry of the monitored modular bridge expansion joint, a cross beam 13 of the monitored modular bridge expansion joint, an intelligent rubber bearing 14 of the monitored modular bridge expansion joint, displacement sensor 15, displacement sensor 2, displacement sensor 3, displacement sensor 4, displacement sensor 5, height sensor 10, height sensor 21, height sensor 3, height sensor 4, height sensor 5, and height sensor 6. The system includes a shaft vibration sensor installation type 1 (24), a triaxial vibration sensor installation type 2 (25), an ultrasonic guided wave transmitter and receiver probe (26), and a water leakage cable sensor (27). Displacement sensor 15 is installed near the center of the opposite side beam 11b. Displacement sensors 26 and 3 (17) are installed on the opposite side beam 11b and symmetrically arranged with a distance D1 from displacement sensor 15. Displacement sensors 15, 26, and 3 (17) are used to measure the displacement from their respective installation positions to the center of the opposite side beam 11b. Displacement sensors 4 (18) and 5 (19) are installed on the opposite side beam. Displacement sensors 18 and 19 are installed on side beam 11b, respectively, and are located close to the two ends of the vertical lane of the monitored modular bridge expansion joint, at a distance of D2. Displacement sensors 18 and 19 are used to measure the vertical displacement from their respective installation positions to side beam 11a. Height sensor 20 is installed on side beam 11a, near its center. Height sensor 21 is installed on the opposite side beam 11b, near its center. Height sensors 22 and 23 are installed on the middle beam 12b, at the center of symmetry of the modular bridge expansion joint, respectively, and are located close to the two ends of the vertical lane of the monitored modular bridge expansion joint, at a distance of D3. Sensor 1 (20), height sensor 2 (21), height sensor 3 (22), and height sensor 4 (23) are used to measure the height of their respective installation positions relative to a fixed height reference point. The triaxial vibration sensor (installation type 1) (24) is installed below the intelligent rubber bearing 14 on the support structure connecting to the central beam 12a of the monitored modular bridge expansion joint. The triaxial vibration sensor (installation type 2) (25) and the ultrasonic guided wave transmitting and receiving probe 26 are installed on the central beam 12a of the monitored modular bridge expansion joint. The leakage cable sensor (27) is installed in a serpentine pattern below the monitored modular bridge expansion joint, with a distribution range as large as possible.The intelligent rubber bearing 14, displacement sensor 15, displacement sensor 2 16, displacement sensor 3 17, displacement sensor 4 18, displacement sensor 5 19, height sensor 1 20, height sensor 2 21, height sensor 3 22, height sensor 4 23, triaxial vibration sensor installation type 1 24, triaxial vibration sensor installation type 2 25, ultrasonic guided wave transmitting and receiving probe 26, and leakage cable sensor 27 are respectively connected to the main unit of the modular bridge expansion joint multi-parameter monitoring device via cables to form signal and power supply paths.

[0038] The modular bridge expansion joint includes multiple monitored central beams 12a and intelligent rubber bearings 14. Multiple triaxial vibration sensors of type two 25 and ultrasonic guided wave transmitters and receivers 26 are installed at locations where the central beams 12a are prone to fracture. Multiple triaxial vibration sensors of type one 24 are installed at locations where the intelligent rubber bearings 14 are prone to detachment. The types of triaxial vibration sensors of type one 24 and type two 25 represent the sensor installation positions: one installed below the intelligent rubber bearings 14 on the support structure connected to the central beams 12a of the monitored modular bridge expansion joint, and the other on the central beams 12a of the monitored modular bridge expansion joint.

[0039] The intelligent rubber support 14 contains a force-measuring sensor element that can measure the supporting force applied to the intelligent rubber support 14.

[0040] Among them, displacement sensor 15, displacement sensor 2 16, displacement sensor 3 17, displacement sensor 4 18, and displacement sensor 5 19 are laser displacement sensors or contact displacement sensors.

[0041] Among them, height sensor 1 20, height sensor 21, height sensor 3 22, and height sensor 4 23 can measure the height between the installation position and the fixed height reference point. Height sensor 1 20, height sensor 21, height sensor 3 22, and height sensor 4 23 are level sensors, laser displacement sensors, or contact displacement sensors. The fixed height reference point should be selected at any fixed position on the bridge.

[0042] Among them, the multi-parameter monitoring device for modular bridge expansion joints needs to select and install all or some of the following components according to actual monitoring requirements: intelligent rubber bearing 14, displacement sensor one 15, displacement sensor two 16, displacement sensor three 17, displacement sensor four 18, displacement sensor five 19, height sensor one 20, height sensor two 21, height sensor three 22, height sensor four 23, triaxial vibration sensor installation type one 24, triaxial vibration sensor installation type two 25, ultrasonic guided wave transmitting and receiving probe 26, and leakage cable sensor 27.

[0043] Among them, the ultrasonic guided wave transmitting and receiving probe 26 is used to couple ultrasonic waves into the middle beam 12a of the monitored modular bridge expansion joint at the installation position and receive ultrasonic echo signals.

[0044] When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the monitoring system should be configured according to the installation positions and functions of the displacement sensor 15, displacement sensor 26, displacement sensor 37, displacement sensor 48, displacement sensor 57, height sensor 10, height sensor 21, height sensor 32, height sensor 43, triaxial vibration sensor installation type 1, triaxial vibration sensor installation type 2, ultrasonic guided wave transmitting and receiving probe 26, and water leakage cable sensor 27 in the modular bridge expansion joint multi-parameter monitoring device. This configuration can also achieve the multi-parameter monitoring function of the bridge expansion joint.

[0045] A multi-parameter monitoring method for modular bridge expansion joints is characterized by acquiring and processing measurement data from the monitored modular bridge expansion joint's intelligent rubber bearing 14, displacement sensor 15, displacement sensor 26, displacement sensor 31, displacement sensor 41, displacement sensor 519, height sensor 120, height sensor 21, height sensor 32, height sensor 423, triaxial vibration sensor installation type 1 24, triaxial vibration sensor installation type 2 25, ultrasonic guided wave transmitting and receiving probe 26, and leakage cable sensor 27 to obtain the monitored data. The monitoring system collects raw data on the six degrees of freedom motion, joint width, load-bearing capacity, triaxial vibration amplitude, triaxial vibration frequency, and water intrusion of the modular bridge expansion joint during operation. Simultaneously, the main unit of the multi-parameter monitoring device further analyzes the data to obtain alarm information on defects such as mechanical interference, vehicle overloading, rubber bearing detachment, central beam fracture, and damaged sealing rubber strips during the movement of the modular bridge expansion joint. The main unit of the multi-parameter monitoring device can send the above raw data and alarm information to a cloud platform via wired or wireless network for data aggregation and real-time display, indicating the operating status and potential defects of the monitored modular bridge expansion joint.

[0046] The relationship between the original motion data of the six degrees of freedom of the modular bridge expansion joint and the measurement results Disp1 of displacement sensor 15, Disp2 of displacement sensor 26, Disp3 of displacement sensor 37, Disp4 of displacement sensor 4, Disp5 of displacement sensor 5, H1 of height sensor 10, H2 of height sensor 21, H3 of height sensor 32, and H4 of height sensor 4, as well as their spatial installation positions, is as follows: the linear displacement along the driving direction is Disp1, and the rotation angle is... Linear displacement perpendicular to the driving direction The corner is The vertical bridge deck linear displacement H1-H2 and the rotation angle are... The distance between displacement sensors 16 and 17 and displacement sensor 15 is D1; ​​the distance between displacement sensors 17 and 18 is D2; and the distance between height sensors 22 and 23 is D3. After obtaining the original data of the six degrees of freedom motion of the modular bridge expansion joint, the gap width of the monitored middle beam 12a of the modular bridge expansion joint should be calculated based on the width and number of the monitored middle beam 12a to determine whether mechanical contact has occurred between the monitored middle beams 12a, so as to obtain the alarm information of mechanical interference in the motion of the modular bridge expansion joint. The calculation of the original data of the six degrees of freedom motion of the modular bridge expansion joint and the alarm information of mechanical interference are completed in the host of the multi-parameter monitoring device of the modular bridge expansion joint.

[0047] The load-bearing capacity measurement results of each intelligent rubber bearing 14 of the monitored modular bridge expansion joint include the preload of the intelligent rubber bearing 14 and the load force of the vehicle passing through the modular bridge expansion joint. When no vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing 14 is the preload F1, and when a vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing 14 is F3. The axle load of the vehicle passing through the modular bridge expansion joint is F3 minus F1. The preload F1 and the axle load of the vehicle can be used to determine whether each rubber bearing has a risk of falling off and to obtain overload alarm information. The preload of each intelligent rubber bearing 14 and the load force of the vehicle passing through the modular bridge expansion joint are calculated in the main unit of the multi-parameter monitoring device of the modular bridge expansion joint, and the vehicle overload and rubber bearing falling off alarm information are obtained.

[0048] The triaxial vibration sensor has a sampling rate of no less than 200 Hz and a single sampling time of no less than 1 second. After each triaxial vibration sensor collects acceleration data once, it performs discrete Fourier transform on the data of the three measurement axes to obtain the vibration spectrum. The amplitude of the maximum amplitude frequency point of the vibration spectrum of the three measurement axes is compared. The amplitude, frequency, and vibration axis of the maximum amplitude frequency point of the measurement axis with the largest amplitude are used as the output data of each triaxial vibration sensor and transmitted to the host of the modular bridge expansion joint multi-parameter monitoring device. The host of the modular bridge expansion joint multi-parameter monitoring device compares the amplitude and frequency of each triaxial vibration sensor with the set threshold. When the amplitude of the triaxial vibration sensor is greater than the threshold, the host of the modular bridge expansion joint multi-parameter monitoring device includes the rubber bearing detachment and the middle beam fracture at the installation position of the triaxial vibration sensor in the alarm information.

[0049] When the sealing rubber strip of the modular bridge expansion joint is damaged, rainwater will come into contact with the leakage cable sensor 27 through the sealing rubber strip. After any part of the leakage cable sensor 27 comes into contact with water, the resistance of the leakage cable sensor 27 will decrease. The host of the multi-parameter monitoring device of the modular bridge expansion joint measures the resistance of the leakage cable sensor 27. When the resistance of the leakage cable sensor 27 is less than the set threshold, the sealing rubber strip damage alarm information can be obtained.

[0050] Among them, the ultrasonic guided wave transmitting and receiving probe 26 can compare the ultrasonic echo signal of the crack-free middle beam 12a of the monitored modular bridge expansion device with the real-time measured ultrasonic echo signal, and evaluate the location and depth of the crack in the middle beam 12a of the monitored modular bridge expansion device based on the changes in the amplitude and phase of the acoustic echo signal.

[0051] When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the multi-parameter monitoring and data processing of other types of bridge expansion joints should be carried out in accordance with any of the methods described in the multi-parameter monitoring methods for modular bridge expansion joints, which can also realize the multi-parameter monitoring function of the bridge expansion joint.

[0052] The working principle of this invention is as follows:

[0053] 1. Processing of raw data for the six-degree-of-freedom motion of a bridge expansion joint:

[0054] a. Under reasonable approximation, the linear displacement of the bridge expansion joint along the driving direction can be represented by the measurement result Disp1 of displacement sensor-15.

[0055] b. Under reasonable approximation conditions, the linear displacement of the bridge expansion joint perpendicular to the traffic direction can be measured using displacement measurement data from displacement sensor 15, displacement sensor 26, and displacement sensor 37, as well as... Figure 2The right triangle relationship formed by the mid-displacement:

[0056]

[0057] Therefore, the linear displacement Δy of the bridge expansion joint perpendicular to the traffic direction can be expressed as:

[0058] c. The linear displacement of the bridge expansion joint in the vertical direction of the bridge deck can be represented as H1-H2 using the height measurement data of height sensor 20 and height sensor 21.

[0059] d. Under reasonable approximation conditions, the turning angle of the bridge expansion joint along the direction of travel can be determined using height measurement data from height sensor 3.22 and height sensor 4.23, as well as... Figure 3 The right triangle relationship in the diagram is represented as follows:

[0060] e. Under reasonable approximation conditions, the vertical turning angle of the bridge expansion joint in the direction of traffic can be determined using height measurement data from height sensor 20 and height sensor 21, displacement measurement data from displacement sensor 15, and... Figure 4 The right triangle relationship in the diagram is represented as follows:

[0061] f. Under reasonable approximation conditions, the vertical bridge deck rotation angle of the bridge expansion joint can be measured using displacement measurement data from displacement sensor 4.18 and displacement sensor 5.19. Figure 5 The right triangle relationship in the diagram is represented as follows:

[0062] 2. Data processing procedure for beam gap width and mechanical interference alarm in bridge expansion joints. After obtaining the linear displacement along the driving direction from the original six-degree-of-freedom motion data of the bridge expansion joint, the spacing of the beams 12a of the monitored modular bridge expansion joint is calculated based on the width and number of beams 12a. If the spacing is greater than zero, there is no mechanical interference; if the spacing is less than zero, there is mechanical interference.

[0063] 3. Data processing procedures for bridge expansion joint load-bearing capacity, vehicle overload, and rubber bearing detachment alarms. The load-bearing capacity measurement result for each intelligent rubber bearing 14 includes the preload of the intelligent rubber bearing 14 and the load force of a vehicle passing over the bridge expansion joint. When no vehicle is passing over the bridge expansion joint, the measurement result for each intelligent rubber bearing 14 is the preload F1. When a vehicle is passing over the bridge expansion joint, the measurement result for each intelligent rubber bearing 14 is F3. The axle load of the vehicle passing over the bridge expansion joint is F3 minus F1. If the preload F1 is less than the threshold, there is a risk of rubber bearing detachment. If the axle load of the vehicle is greater than the threshold, the vehicle passing over the bridge expansion joint is overloaded.

[0064] 4. Data processing procedure for triaxial vibration amplitude, triaxial vibration frequency, and alarms for rubber bearing detachment and middle beam fracture of bridge expansion joints. After each triaxial vibration sensor collects acceleration data once, discrete Fourier transform is performed on the data of the three measurement axes to obtain the vibration spectrum. The amplitude of the maximum amplitude frequency point of the vibration spectrum of the three measurement axes is compared. The amplitude, frequency, and vibration axis of the maximum amplitude frequency point of the measurement axis with the largest amplitude are used as the output data of each triaxial vibration sensor. The amplitude and frequency of each triaxial vibration sensor are compared with the set threshold. When the amplitude of the triaxial vibration sensor is greater than the threshold, it indicates that the mechanical connection status of the installation position of the triaxial vibration sensor has changed. The possible cause is the detachment of the bearing or the fracture of the middle beam near the installation position. The middle beam at the installation position of the triaxial vibration sensor is then included in the middle beam fracture alarm information.

[0065] 5. Data processing procedure for water intrusion and sealing rubber strip damage alarms of bridge expansion joints. When the sealing rubber strip of a bridge expansion joint is damaged, rainwater will come into contact with the leakage cable sensor 27 through the sealing rubber strip. After any part of the leakage cable sensor 27 comes into contact with water, the resistance of the leakage cable sensor 27 will decrease. The main unit of the modular bridge expansion joint multi-parameter monitoring device measures the resistance of the leakage cable sensor 27. When the resistance of the leakage cable sensor 27 is less than the set threshold, the sealing rubber strip damage alarm information can be obtained.

[0066] 6. The ultrasonic guided wave transmitting and receiving probe 26 is used to couple ultrasonic waves into the central beam at the installation location and receive ultrasonic echo signals. It can compare the ultrasonic echo signals of the central beam without cracks with the real-time measured ultrasonic echo signals. The principle is that when microcracks are generated inside the central beam, the echo amplitude of the ultrasonic guided wave will be enhanced, and the phase will change depending on the location of the crack. Therefore, the location and depth of the crack in the central beam can be evaluated based on the changes in the amplitude and phase of the acoustic echo signal.

[0067] The technological innovations and beneficial effects of the modular bridge expansion joint multi-parameter monitoring device and method are as follows: This invention utilizes the fusion of multiple sensors, including intelligent rubber bearings, displacement sensors, height sensors, triaxial vibration sensors, ultrasonic guided wave transmitters and receivers, and leakage cable sensors, to monitor multiple raw operating parameters of the bridge expansion joint, such as six degrees of freedom motion, joint width, load-bearing capacity, triaxial vibration amplitude, triaxial vibration frequency, ultrasonic echo signal characteristics, and water intrusion. Simultaneously, by combining the causes and results of bridge expansion joint defects, the raw data collected by the sensors is analyzed in depth to obtain information on defects such as mechanical interference, vehicle overloading, rubber bearing detachment, central beam fracture, and sealing rubber strip damage during the bridge expansion joint's movement. The alarm information; the main unit of the multi-parameter monitoring device for bridge expansion joints can send the above raw data and alarm information to the cloud platform through wired or wireless networks to complete data aggregation and real-time display, and remotely prompt the bridge maintenance unit of the operating status and potential defects of the monitored bridge expansion joints; it has strong applicability to other types of expansion joints. When the monitored bridge expansion joint is not a modular bridge expansion joint, the monitoring system can be set up according to the installation positions of the displacement sensor, height sensor, triaxial vibration sensor, ultrasonic guided wave transmitting and receiving probe, and leakage cable sensor in the multi-parameter monitoring device for modular bridge expansion joints, and the same data processing method can be used to realize the multi-parameter monitoring function of the bridge expansion joint.

Claims

1. A multi-parameter monitoring device for a modular bridge expansion joint, comprising a side beam (11a) of the monitored modular bridge expansion joint, a side beam (11b) of the monitored modular bridge expansion joint, a middle beam (12a) of the monitored modular bridge expansion joint, a middle beam (12b) at the center of symmetry of the monitored modular bridge expansion joint, a cross beam (13) of the monitored modular bridge expansion joint, an intelligent rubber bearing (14) of the monitored modular bridge expansion joint, a displacement sensor one (15), a displacement sensor two (16), a displacement sensor three (17), and a displacement sensor four (18). 18), Displacement sensor five (19), Height sensor one (20), Height sensor two (21), Height sensor three (22), Height sensor four (23), Triaxial vibration sensor installation type one (24), Triaxial vibration sensor installation type two (25), Ultrasonic guided wave transmitting and receiving probe (26), Leakage cable sensor (27), wherein displacement sensor one (15) is installed near the center of the opposite side beam (11b), and displacement sensor two (16) and displacement sensor three (17) are installed on the opposite side beam (11b). b) The displacement sensors 1 (15), 2 (16), and 3 (17) are symmetrically arranged at a distance D1 from the displacement sensor 1 (15). The displacement sensors 1 (15), 2 (16), and 3 (17) are used to measure the displacement from their respective installation positions to the center of the opposite side beam (11b). The displacement sensors 4 (18) and 5 (19) are installed on the opposite side beam (11b) and are close to the two ends of the vertical carriageway of the monitored modular bridge expansion joint at a distance D2. The displacement sensors 4 (18) and 5 (19) are used to measure the vertical displacement from their respective installation positions to the side beam (11a). The height sensor 1 (20) is installed on the side beam (11a) and close to the center. The height sensor 2 (21) is installed on the opposite side beam (11b) and close to the center. The height sensors 3 (22) and 4 (23) are installed on the modular bridge expansion joint. The height sensors 1 (20), 2 (21), 3 (22), and 4 (23) are installed on the central beam (12b) at the center of the symmetrical center of the modular bridge expansion joint and are respectively close to the two ends of the perpendicular carriageway of the monitored modular bridge expansion joint, at a distance of D3. The height sensors 1 (20), 2 (21), 3 (22), and 4 (23) are respectively used to measure the height between their respective installation positions and a fixed height reference point. The triaxial vibration sensor installation type 1 (24) is installed on the support structure connected to the central beam (12a) of the monitored modular bridge expansion joint below the intelligent rubber bearing (14). The triaxial vibration sensor installation type 2 (25) and the ultrasonic guided wave transmitting and receiving probe (26) are installed on the central beam (12a) of the monitored modular bridge expansion joint. The water leakage cable sensor (27) is installed in a serpentine manner below the monitored modular bridge expansion joint and the distribution range is as large as possible.The intelligent rubber bearing (14), displacement sensor one (15), displacement sensor two (16), displacement sensor three (17), displacement sensor four (18), displacement sensor five (19), height sensor one (20), height sensor two (21), height sensor three (22), height sensor four (23), triaxial vibration sensor installation type one (24), triaxial vibration sensor installation type two (25), ultrasonic guided wave transmitting and receiving probe (26), and leakage cable sensor (27) are respectively connected to the main unit of the modular bridge expansion joint multi-parameter monitoring device via cables to form signal and power supply paths.

2. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: The modular bridge expansion joint includes multiple monitored modular bridge expansion joints with a central beam (12a) and a smart rubber bearing (14). Multiple triaxial vibration sensors of type II (25) and ultrasonic guided wave transmitter and receiver probes (26) are installed at locations where the central beam (12a) of the monitored modular bridge expansion joint is prone to breakage. Multiple triaxial vibration sensors of type I (24) are installed at locations where the smart rubber bearing (14) is prone to detachment. The types of triaxial vibration sensors of type I (24) and type II (25) represent the types of sensor installation locations, respectively, installed on the support structure connected to the central beam (12a) of the monitored modular bridge expansion joint below the smart rubber bearing (14) and on the central beam (12a) of the monitored modular bridge expansion joint.

3. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: The intelligent rubber bearing (14) contains a force sensing element that can measure the supporting force applied to the intelligent rubber bearing (14).

4. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: Displacement sensor 1 (15), displacement sensor 2 (16), displacement sensor 3 (17), displacement sensor 4 (18), and displacement sensor 5 (19) are laser displacement sensors or contact displacement sensors.

5. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: Height sensor 1 (20), height sensor 2 (21), height sensor 3 (22), and height sensor 4 (23) can measure the height between the installation position and the fixed height reference point. Height sensor 1 (20), height sensor 2 (21), height sensor 3 (22), and height sensor 4 (23) are level sensors, laser displacement sensors, or contact displacement sensors. The fixed height reference point should be selected at any fixed position on the bridge.

6. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: The multi-parameter monitoring device for modular bridge expansion joints needs to select and install all or some of the following components according to actual monitoring requirements: intelligent rubber bearing (14), displacement sensor one (15), displacement sensor two (16), displacement sensor three (17), displacement sensor four (18), displacement sensor five (19), height sensor one (20), height sensor two (21), height sensor three (22), height sensor four (23), triaxial vibration sensor installation type one (24), triaxial vibration sensor installation type two (25), ultrasonic guided wave transmitting and receiving probe (26), and water leakage cable sensor (27).

7. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: An ultrasonic guided wave transmitter and receiver probe (26) is used to couple ultrasonic waves into the central beam (12a) of the monitored modular bridge expansion joint at the installation location and to receive ultrasonic echo signals.

8. The modular bridge expansion joint multi-parameter monitoring device according to claim 1, characterized in that: When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the monitoring system should be configured according to the installation positions and functions of the displacement sensor 1 (15), displacement sensor 2 (16), displacement sensor 3 (17), displacement sensor 4 (18), displacement sensor 5 (19), height sensor 1 (20), height sensor 2 (21), height sensor 3 (22), height sensor 4 (23), triaxial vibration sensor installation type 1 (24), triaxial vibration sensor installation type 2 (25), ultrasonic guided wave transmitting and receiving probe (26), and water leakage cable sensor (27) in the modular bridge expansion joint multi-parameter monitoring device described in claim 1. This system can also realize the multi-parameter monitoring function of the bridge expansion joint.

9. A multi-parameter monitoring method for modular bridge expansion joints, characterized in that... The multi-parameter monitoring device for modular bridge expansion joints collects and processes measurement data from the monitored modular bridge expansion joints, including the intelligent rubber bearing (14), displacement sensor 1 (15), displacement sensor 2 (16), displacement sensor 3 (17), displacement sensor 4 (18), displacement sensor 5 (19), height sensor 1 (20), height sensor 2 (21), height sensor 3 (22), height sensor 4 (23), triaxial vibration sensor installation type 1 (24), triaxial vibration sensor installation type 2 (25), ultrasonic guided wave transmitting and receiving probe (26), and water leakage cable sensor (27). The system obtains raw data on the six degrees of freedom motion, joint width, load-bearing capacity, triaxial vibration amplitude, triaxial vibration frequency, and water intrusion of the monitored modular bridge expansion joint. Simultaneously, the main unit of the multi-parameter monitoring device further analyzes the data to obtain alarm information on defects such as mechanical interference, vehicle overloading, rubber bearing detachment, central beam fracture, and damaged sealing rubber strips. The main unit can send the above raw data and alarm information to a cloud platform via wired or wireless network for data aggregation and real-time display, indicating the operating status and potential defects of the monitored modular bridge expansion joint.

10. The multi-parameter monitoring method for modular bridge expansion joints as described in claim 9, characterized in that: The relationship between the original data of the six-degree-of-freedom motion of the modular bridge expansion joint and the measurement results of displacement sensor 1 (15), Disp1, displacement sensor 2 (16), displacement sensor 3 (17), displacement sensor 4 (18), displacement sensor 5 (19), height sensor 1 (20), height sensor 2 (21), height sensor 3 (22), height sensor 4 (23), and their spatial installation positions is as follows: the linear displacement along the driving direction is Disp1, and the rotation angle is... Linear displacement perpendicular to the driving direction The corner is The vertical bridge deck linear displacement H1-H2 and the rotation angle are... The distance between displacement sensor 2 (16) and displacement sensor 3 (17) and displacement sensor 1 (15) is D1, the distance between displacement sensor 3 (17) and displacement sensor 4 (18) is D2, and the distance between height sensor 3 (22) and height sensor 4 (23) is D3. After obtaining the original data of the six degrees of freedom motion of the modular bridge expansion joint, the joint width of the monitored middle beam (12a) of the modular bridge expansion joint should be calculated according to the width and number of the monitored middle beam (12a) of the modular bridge expansion joint, so as to determine whether mechanical contact occurs between the middle beams (12a) of the monitored modular bridge expansion joint, so as to obtain the alarm information of mechanical interference in the motion of the modular bridge expansion joint. The calculation of the original data of the six degrees of freedom motion of the modular bridge expansion joint and the alarm information of mechanical interference are completed in the host of the multi-parameter monitoring device of the modular bridge expansion joint.

11. The multi-parameter monitoring method for modular bridge expansion joints as described in claim 9, characterized in that: The load-bearing capacity measurement results of each intelligent rubber bearing (14) of the monitored modular bridge expansion joint include the preload of the intelligent rubber bearing (14) and the load force of the vehicle passing through the modular bridge expansion joint. When no vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing (14) is the preload F1. When a vehicle passes through the modular bridge expansion joint, the measurement result of each intelligent rubber bearing (14) is F3. The axle load of the vehicle passing through the modular bridge expansion joint is F3 minus F1. The preload F1 and the axle load of the vehicle can be used to determine whether each rubber bearing has a risk of falling off and overload alarm information. The preload of each intelligent rubber bearing (14) and the load force of the vehicle passing through the modular bridge expansion joint are calculated in the host of the multi-parameter monitoring device of the modular bridge expansion joint, and the vehicle overload and rubber bearing falling off alarm information are obtained.

12. The multi-parameter monitoring method for modular bridge expansion joints as described in claim 9, characterized in that: The sampling rate of the triaxial vibration sensor is no less than 200 Hz, and the single sampling time is no less than 1 second. After each triaxial vibration sensor collects acceleration data once, it performs discrete Fourier transform on the data of the three measurement axes to obtain the vibration spectrum. The amplitude of the maximum amplitude frequency point of the vibration spectrum of the three measurement axes is compared. The amplitude, frequency, and vibration axis of the maximum amplitude frequency point of the measurement axis with the largest amplitude are used as the output data of each triaxial vibration sensor and transmitted to the host of the modular bridge expansion joint multi-parameter monitoring device. The host of the modular bridge expansion joint multi-parameter monitoring device compares the amplitude and frequency of each triaxial vibration sensor with the set threshold. When the amplitude of the triaxial vibration sensor is greater than the threshold, the host of the modular bridge expansion joint multi-parameter monitoring device includes the rubber bearing detachment and the middle beam fracture at the installation position of the triaxial vibration sensor in the alarm information.

13. The multi-parameter monitoring method for modular bridge expansion joints as described in claim 9, characterized in that: When the sealing rubber strip of the modular bridge expansion joint is damaged, rainwater will come into contact with the leakage cable sensor (27) through the sealing rubber strip of the modular bridge expansion joint. After the leakage cable sensor (27) comes into contact with water at any position, the resistance of the leakage cable sensor (27) will decrease. The host of the multi-parameter monitoring device of the modular bridge expansion joint measures the resistance of the leakage cable sensor (27). When the resistance of the leakage cable sensor (27) is less than the set threshold, the sealing rubber strip damage alarm information can be obtained.

14. The modular bridge expansion joint multi-parameter monitoring device according to claim 9, characterized in that: The ultrasonic guided wave transmitter and receiver probe (26) can compare the ultrasonic echo signal of the crack-free middle beam (12a) of the monitored modular bridge expansion device with the real-time measured ultrasonic echo signal, and evaluate the location and depth of the crack in the middle beam (12a) of the monitored modular bridge expansion device based on the changes in the amplitude and phase of the acoustic echo signal.

15. The multi-parameter monitoring method for modular bridge expansion joints as described in claim 9, characterized in that: When monitoring a bridge expansion joint that is not a modular bridge expansion joint, the method described in any one of claims 9, 10, 11, 12, 13, and 14 should be used to implement multi-parameter monitoring and data processing for other types of bridge expansion joints, which can also realize the multi-parameter monitoring function of the bridge expansion joint.

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