Device for monitoring three-dimensional displacement and inclination of a support and method for evaluating voiding

Abstract

The device for monitoring three-dimensional displacement and inclination of a support and the void evaluation method belong to the technical field of bridge monitoring. In order to make a judgment and give a warning for the void in a certain direction of a bridge support, the upper protection box and the lower protection box are arranged in a top-down manner, the inclination measuring device is arranged in the upper protection box, the void sensing device is arranged in the lower protection box, and the lower protection box is connected with the lower fixed base. The inclination measuring device is composed of two groups and is arranged in the xz direction and the yz direction in the upper protection box respectively. The void sensing device is composed of four groups and is arranged in the four corner directions in the lower protection box respectively. The top fixed disc is installed at the top of the void sensing rod, the void sensing rod passes through the upper protection box and is connected with the cross support, the cross support is hinged with the void sensing device, the top fixed disc is fixedly connected with the bridge beam body, and the lower fixed base is fixedly connected with the bridge pier. The void measuring error is effectively avoided.

Description

Technical Field

[0001] This invention belongs to the field of bridge monitoring technology, specifically relating to a device for synchronously monitoring the three-dimensional displacement and tilt of bearings and a method for assessing voids. Background Technology

[0002] Bridge bearings are crucial components connecting the superstructure and substructure of a bridge. They reliably transfer the reactions and deformations (displacement and rotation) of the superstructure to the substructure, ensuring that the stress and deformation of the bridge beams match theoretical calculations. Their quality and performance directly impact the bridge's usability and durability. Due to poor construction or subsequent operation, bearing defects are quite common, manifesting as bearing detachment, uneven load distribution, bearing plate twisting and fracture, weld cracking, bearing displacement exceeding allowable deviation, permanent deformation, and breakage of fixing pins. Uneven stress or detachment of the bearings alters the structural stress pattern, causing changes in the internal forces of the main beam, crossbeams, and bearing reactions, damaging the main beam, bridge deck, and piers, and reducing the bearing's service life.

[0003] In conventional bridge safety monitoring systems, the relative displacement between the main girder and the piers is often monitored to detect instability issues such as overturning and slippage. Currently, most bridge overturning prevention measures involve structural reinforcement at the bearings, which cannot monitor stress levels and box girder attitude in real time. Even with pot bearings using sensor units, the sensor units are generally large and difficult to fit into the bearings. Even if they are placed, they pose safety hazards to the mechanical properties of the bearings. Furthermore, conventional bearings using sensor units cannot provide information on the stress conditions in all directions of the bearing, thus failing to accurately determine and warn of bearing slippage in a specific direction.

[0004] Since the performance of bearings affects the long-term durability of bridges, timely repair and replacement of bearings can reduce secondary damage, extend the service life of bridges, and reduce overall maintenance costs. However, bearing defects are quite common, and there is a lack of unified evaluation standards for bearing performance, making it impossible to objectively and quantitatively assess the priority of repair and replacement among numerous bearing defects. Summary of the Invention

[0005] The problem this invention aims to solve is to accurately judge and warn of the detachment of a bearing in a certain direction, effectively reducing the risk of bridge overturning caused by bearing detachment. It proposes a device and a detachment assessment method for simultaneously monitoring the three-dimensional displacement and tilt of the bearing.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A device for synchronously monitoring the three-dimensional displacement and tilt of a support includes a top fixed plate, a release sensing rod, an upper protective box, a tilt measuring device, a lower protective box, a release sensing device, a lower fixed base, and a cross support rod. The upper and lower protective boxes are arranged vertically. The tilt measuring device is placed in the upper protective box, and the detachment sensing device is placed in the lower protective box. The lower protective box is connected to the lower fixed chassis. The tilt measuring device consists of two sets, which are respectively set in the xz and yz directions in the upper protective box. The detachment sensing device consists of four sets, which are respectively set in the four apex directions in the lower protective box. The tilt measuring device includes two first cylindrical bodies arranged side by side on the bottom plate of the upper protective box. Each first cylindrical body is provided with a first bottom disk and a first magnetic induction plate inside. The lower end of the first cylindrical rod is connected to the first bottom disk. The first bottom disk is located above the first magnetic induction plate. The first bottom disk and the upper surface of the first magnetic induction plate have the same magnetism. A first fiber optic strain sensor is attached to the lower surface of the first magnetic induction plate. The upper ends of the two first cylindrical rods are hinged to both ends of a connecting rod. The middle part of the connecting rod is hinged to a support rod. The lower end of the support rod is fixed to the bottom plate of the upper protective box. The top fixing plate is installed on the top of the de-emptying sensing rod, the de-emptying sensing rod passes through the upper protective box and is connected to the cross support rod, and the cross support rod and the de-emptying sensing device are hinged together; The detachment sensing device includes a second cylindrical body, and each second cylindrical body is provided with a second bottom disk and a second magnetic sensing plate inside. The upper end of the second cylindrical rod is hinged to the cross support rod, and the lower end of the second cylindrical rod is connected to the second bottom disk. The second bottom disk is located above the second magnetic sensing plate. The second bottom disk and the upper surface of the second magnetic sensing plate have the same magnetism. A second fiber optic strain sensor is attached to the lower surface of the second magnetic sensing plate. The top fixing plate is fixedly connected to the bridge beam, and the lower fixing base is fixedly connected to the bridge pier.

[0007] Furthermore, the tilt measuring device also includes a fiber optic temperature compensation sensor, which is placed on the outside of the first cylindrical body and connected to the first fiber optic strain sensor via an optical fiber.

[0008] Furthermore, the vacancy sensing device also includes a fiber optic temperature compensation sensor, which is placed on the outside of the second cylindrical body and connected to the second fiber optic strain sensor via an optical fiber.

[0009] A method for evaluating the clearance of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, based on the aforementioned device for synchronously monitoring the three-dimensional displacement and tilt of a support, includes the following steps: S1. For a device for synchronously monitoring the three-dimensional displacement and tilt of the support installed on each bridge pier, the tilt angle measuring device in the xz direction collects the strain data of the fiber optic strain sensor in the xz direction, the tilt angle measuring device in the yz direction collects the strain data of the fiber optic strain sensor in the yz direction, and the four delamination sensing devices collect the fiber optic strain sensor data in the four directions. S2. Based on the data obtained in step S1, calculate the displacement X in the x direction, the displacement Y in the y direction, and the displacement Z in the z direction of the bridge support; S3. Using the wavelet transform principle, the displacements X, Y, and Z of the bridge supports in the x-direction, y-direction, z-direction, xz-direction tilt angle bx, and yz-direction tilt angle by of the bridge supports obtained in step S2 are preprocessed to remove noise interference factors, resulting in the following calculation formula: X1 = XO(X); Where O(X) is the displacement in the x direction caused by external noise interference, and X1 is the displacement of the bridge support in the x direction after preprocessing with wavelet transform. Y1 = YO(Y); Where O(Y) is the displacement in the y direction caused by external noise interference, and Y1 is the displacement of the bridge support in the y direction after preprocessing with wavelet transform. Z1 = ZO(Z); Where O(Z) is the displacement in the z direction caused by external noise interference, and Z1 is the displacement of the bridge support in the z direction after wavelet transform preprocessing. bx1 = bx - O(bx); Where O(bx) is the tilt angle in the xz direction caused by external noise interference, and bx1 is the tilt angle in the xz direction after preprocessing with wavelet transform; by1 = by - O(by); Where O(by) is the tilt angle in the yz direction caused by external noise interference, and by1 is the tilt angle in the yz direction after preprocessing with wavelet transform. S4. Compare the displacement of each support at time t1 obtained in step S3 with the displacement at time t2 to obtain the displacement change values ​​in the x direction, y direction, z direction, xz direction tilt change value, and yz direction tilt change value at time t1 and time t2, and then form a matrix in the time domain. S5. Using the cross-correlation function, calculate the cross-correlation coefficient between arrays in adjacent time domains from the matrix obtained in step S4 to obtain the trend matrix of the support in the time domain. The cross-correlation function The calculation formula is: )= ; in, This represents the cross-correlation coefficient across adjacent time domains; S6. Evaluate the condition of the bridge supports based on the trend matrix of the supports in the time domain obtained in step S5.

[0010] Furthermore, the specific implementation method of step S2 includes the following steps: S2.1. The formula for calculating the displacement X of a bridge support in the x-direction is: X = m(1 - cosbx); Where m is the length of the connecting rod of the tilt measuring device in the xz direction, and bx is the tilt angle in the xz direction; bx is obtained by fitting data collected by the fiber optic strain sensor in the tilt measurement device in the xz direction. The calculation expression is: ; in, The first data fitting coefficient is... The fitting coefficients for the second data are... This is the first data from the fiber optic strain sensor inside the tilt measurement device in the xz direction. The second data is from the fiber optic strain sensor inside the tilt measurement device in the xz direction; S2.2. The formula for calculating the displacement Y of a bridge support in the y-direction is: Y = n(1 - coxby); Where n is the length of the connecting rod of the tilt measuring device in the yz direction, and by is the tilt angle in the yz direction; The value of 'by' is obtained by fitting data collected from fiber optic strain sensors in the tilt measurement device along the yz direction. The calculation expression is as follows: ; in, The fitting coefficients for the third data are... The fourth data fitting coefficient, This is the third data from the fiber optic strain sensor inside the tilt measurement device in the yz direction. This is the fourth data from the fiber optic strain sensor inside the tilt measurement device in the yz direction; S2.3. The formula for calculating the displacement Z of the bridge support in the z-direction is: ; in, , , , The values ​​are the strain data of the four fiber optic strain sensors in the de-emptying sensing device, and d is the thickness of the second magnetic induction disc in the de-emptying sensing device.

[0011] Furthermore, the specific implementation method of step S4 includes the following steps: S4.1. Calculate the displacement change in the x-direction at time t1 and time t2. ,in and These are the x-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.2. Calculate the displacement changes in the y-direction at time t1 and time t2. ,in and These are the y-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.3. Calculate the displacement change in the z-direction at time t1 and time t2. ,in and These are the z-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.4. Calculate the change in tilt in the xz direction at time t1 and time t2. ,in and These represent the xz-direction tilt after noise reduction preprocessing at times t1 and t2, respectively. S4.5. Calculate the change in tilt along the yz direction at time t1 and time t2. ,in and These represent the tilt in the yz direction after noise reduction preprocessing at times t1 and t2, respectively. S4.6. Construct the matrix in the time domain; the calculation expression is as follows: .

[0012] Furthermore, the support variation trend matrix in the time domain in step S5 includes the support displacement variation trend matrix and the support tilt variation trend matrix in the time domain. The expression for the support displacement variation trend matrix in the time domain is: ; The expression for the trend matrix of the inclination change of the support in the time domain is: .

[0013] The beneficial effects of this invention are: This invention discloses a device for synchronously monitoring the three-dimensional displacement and tilt of a support. Combining the piston compression and tension principle, the top fixed plate is fully connected and fixed to the beam, and the lower fixed base is fully connected and fixed to the pier. The void sensing device consists of a cylindrical rod, a bottom disc of the cylindrical rod, a sensing disc, and a fiber optic strain sensor, with the fiber optic strain sensor attached to the bottom surface of the sensing disc. When the beam and pier experience relative displacement, i.e., when the support experiences vertical voiding, the void sensing rod is stretched and compressed, thereby causing changes in the void sensing device. There are a total of four void sensing devices, effectively avoiding void measurement errors caused by a single direction. When the void sensing rod moves downward or upward, the cylindrical rod of the void sensing device will compress or move upward, causing corresponding compression or stretching deformation on the lower surface of the sensing disc. The fiber optic strain sensor can detect minute deformations in real time. By experimentally fitting the relationship between the void amount and the fiber optic strain change, the void value can be reflected later using data from the fiber optic strain sensor.

[0014] This invention discloses a device for synchronously monitoring the three-dimensional displacement and tilt of a support. The upper tilt angle measuring device is mainly divided into an XZ direction tilt angle measuring device and a YZ direction tilt angle measuring device. This device combines the lever principle and the magnetic repulsion principle. When the device tilts in a certain direction, due to the influence of gravity and the lever principle, the bottom disc of the cylindrical rod of the tilt angle measuring device will press downwards against the upper surface of the magnetic induction disc. The bottom disc and the upper surface of the magnetic induction disc have the same magnetism, and the pressing generates a repulsive force, causing deformation of the lower surface of the magnetic induction disc. A fiber optic strain sensor is attached to the lower surface of the magnetic induction disc, which can sense the minute deformation of the lower surface of the magnetic induction disc in real time. When the tilt returns to its original state, i.e., when no tilt occurs, gravity weakens until it disappears, and the magnetic repulsion force causes the cylindrical rod to return to its original shape. By experimentally fitting the relationship between the tilt angle and the fiber optic strain change, the tilt angle value in that direction can be reflected later through the data from the fiber optic strain sensor.

[0015] This invention discloses a device for synchronously monitoring the three-dimensional displacement and tilt of bearings. The upper omnidirectional tilt measurement device and the lower void induction device are each equipped with a fiber optic grating temperature-compensated sensor. This allows for real-time temperature compensation of the fiber optic grating strain sensor and also enables real-time monitoring of temperature changes near the bearing. Since bridge health monitoring systems are typically installed after bridge construction, when dead load and shrinkage / creep effects have been completed, sensors installed later cannot measure the resulting relative displacement. Therefore, relative displacement is only considered in relation to the horizontal shear force under temperature and traffic loads. Voiding caused by temperature changes is relatively slow, long-term, and linearly related to temperature. Voiding caused by vehicle loads is short-term and noticeable. When vehicles pass over the bridge, vertical deformation occurs, which is reflected at the bearings as voiding or vertical displacement. By understanding the voiding patterns of both, the relationship between temperature and bearing voiding can be fitted. Subtracting the temperature effect value from the monitored value yields the bridge voiding value caused by vehicle loads. By setting a detachment threshold, when the support becomes detached due to the combined effects of vehicle load and temperature, the monitoring system will issue an alarm if the threshold is exceeded. Attached Figure Description

[0016] Figure 1 This is a front view of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, as described in this invention. Figure 2 This is a top view of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, as described in this invention. Figure 3 This is a bottom view of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, as described in this invention. Figure 4 This is a perspective view of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, as described in this invention. Figure 5 This is a flowchart of a collaborative verification method for a device for synchronously monitoring the three-dimensional displacement and tilt of a support, as described in this invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described specific embodiments are merely a part of the embodiments of the invention, and not all of them. The components of the specific embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations, and the invention may also have other embodiments.

[0018] Therefore, the following detailed description of specific embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected specific embodiments of the invention. All other specific embodiments obtained by those skilled in the art based on these specific embodiments without inventive effort are within the scope of protection of this invention.

[0019] To further understand the invention's content, features, and effects, the following specific embodiments are provided, along with accompanying drawings. Figure 1 -Appendix Figure 5 Detailed explanation is as follows: Specific implementation method one:

[0020] A device for synchronously monitoring the three-dimensional displacement and tilt of a support includes a top fixed plate 1, a void sensing rod 2, an upper protective box 3, a tilt measuring device 4, a lower protective box 5, a void sensing device 7, a lower fixed base plate 6, and a cross support rod 8. The upper protective housing 3 and the lower protective housing 5 are arranged vertically. The tilt angle measuring device 4 is placed inside the upper protective housing 3, and the detachment sensing device 7 is placed inside the lower protective housing 5. The lower protective housing 5 is connected to the lower fixed chassis 6. The tilt angle measuring device 4 consists of two sets, which are respectively set in the xz direction and yz direction inside the upper protective housing 3. The detachment sensing device 7 consists of four sets, which are respectively set in the four apex directions inside the lower protective housing 5. The tilt measuring device 4 includes two first cylindrical bodies 4-5 arranged side by side on the bottom plate of the upper protective box 3. Each first cylindrical body 4-5 is provided with a first bottom disk 4-3 and a first magnetic induction plate 4-4 inside. The lower end of the first cylindrical rod 4-2 is connected to the first bottom disk 4-3. The first bottom disk 4-3 is located above the first magnetic induction plate 4-4. The upper surfaces of the first bottom disk 4-3 and the first magnetic induction plate 4-4 have the same magnetism. A first fiber optic strain sensor 4-6 is attached to the lower surface of the first magnetic induction plate 4-4. The upper ends of the two first cylindrical rods 4-2 are hinged to both ends of the connecting rod 4-1. The middle part of the connecting rod 4-1 is hinged to the support rod 4-7. The lower end of the support rod 4-7 is fixed to the bottom plate of the upper protective box 3. The top fixing plate 1 is installed on the top of the de-emptying sensing rod 2. The de-emptying sensing rod 2 passes through the upper protective box 3 and is connected to the cross support rod 8. The cross support rod 8 and the de-emptying sensing device 7 are hinged. The detachment sensing device 7 includes a second cylindrical body 7-5. Each second cylindrical body 7-5 is provided with a second bottom disk 7-3 and a second magnetic sensing plate 7-2 inside. The upper end of the second cylindrical rod 7-1 is hinged to the cross support rod 8, and the lower end of the second cylindrical rod 7-1 is connected to the second bottom disk 7-3. The second bottom disk 7-3 is located above the second magnetic sensing plate 7-2. The second bottom disk 7-3 and the upper surface of the second magnetic sensing plate 7-2 have the same magnetism. A second fiber optic strain sensor 7-4 is attached to the lower surface of the second magnetic sensing plate 7-2. The top fixing plate 1 is fixedly connected to the bridge beam, and the lower fixing base plate 6 is fixedly connected to the bridge pier.

[0021] Furthermore, the tilt measuring device 4 also includes a fiber optic grating temperature compensation sensor, which is placed on the outside of the first cylindrical body 4-5 and connected to the first fiber optic grating strain sensor 4-6 via optical fiber.

[0022] Furthermore, the vacancy sensing device 7 also includes a fiber optic temperature compensation sensor, which is placed on the outside of the second cylindrical body 7-5 and connected to the second fiber optic strain sensor 7-4 via an optical fiber.

[0023] Furthermore, the device for synchronously monitoring the three-dimensional displacement and tilt of the support described in this embodiment is based on piston compression, utilizing magnetic repulsion deformation to measure the tilt angle, and utilizing air compression to deform the disc and measure the void value. Specific Implementation Method Two:

[0025] A method for evaluating the clearance of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, based on the device for synchronously monitoring the three-dimensional displacement and tilt of a support described in Specific Embodiment 1, includes the following steps: S1. For a device for synchronously monitoring the three-dimensional displacement and tilt of the support installed on each bridge pier, the tilt angle measuring device in the xz direction collects the strain data of the fiber optic strain sensor in the xz direction, the tilt angle measuring device in the yz direction collects the strain data of the fiber optic strain sensor in the yz direction, and the four delamination sensing devices collect the fiber optic strain sensor data in the four directions. S2. Based on the data obtained in step S1, calculate the displacement X in the x direction, the displacement Y in the y direction, and the displacement Z in the z direction of the bridge support; Furthermore, the specific implementation method of step S2 includes the following steps: S2.1. The formula for calculating the displacement X of a bridge support in the x-direction is: X = m(1 - cosbx); Where m is the length of the connecting rod of the tilt measuring device in the xz direction, and bx is the tilt angle in the xz direction; bx is obtained by fitting data collected by the fiber optic strain sensor in the tilt measurement device in the xz direction. The calculation expression is: ; in, The first data fitting coefficient is... The fitting coefficients for the second data are... This is the first data from the fiber optic strain sensor inside the tilt measurement device in the xz direction. The second data is from the fiber optic strain sensor inside the tilt measurement device in the xz direction; S2.2. The formula for calculating the displacement Y of a bridge support in the y-direction is: Y = n(1 - coxby); Where n is the length of the connecting rod of the tilt measuring device in the yz direction, and by is the tilt angle in the yz direction; The value of 'by' is obtained by fitting data collected from fiber optic strain sensors in the tilt measurement device along the yz direction. The calculation expression is as follows: ; in, The fitting coefficients for the third data are... The fourth data fitting coefficient, This is the third data from the fiber optic strain sensor inside the tilt measurement device in the yz direction. This is the fourth data from the fiber optic strain sensor inside the tilt measurement device in the yz direction; S2.3. The formula for calculating the displacement Z of the bridge support in the z-direction is: ; in, , , , These are the strain data of the four fiber optic strain sensors in the de-emptying sensing device, and d is the thickness of the second magnetic induction disc in the de-emptying sensing device. S3. Using the wavelet transform principle, the displacements X, Y, and Z of the bridge supports in the x-direction, y-direction, z-direction, xz-direction tilt angle bx, and yz-direction tilt angle by of the bridge supports obtained in step S2 are preprocessed to remove noise interference factors, resulting in the following calculation formula: X1 = XO(X); Where O(X) is the displacement in the x direction caused by external noise interference, and X1 is the displacement of the bridge support in the x direction after preprocessing with wavelet transform. Y1 = YO(Y); Where O(Y) is the displacement in the y direction caused by external noise interference, and Y1 is the displacement of the bridge support in the y direction after preprocessing with wavelet transform. Z1 = ZO(Z); Where O(Z) is the displacement in the z direction caused by external noise interference, and Z1 is the displacement of the bridge support in the z direction after wavelet transform preprocessing. bx1 = bx - O(bx); Where O(bx) is the tilt angle in the xz direction caused by external noise interference, and bx1 is the tilt angle in the xz direction after preprocessing with wavelet transform; by1 = by - O(by); Where O(by) is the tilt angle in the yz direction caused by external noise interference, and by1 is the tilt angle in the yz direction after preprocessing with wavelet transform. S4. Compare the displacement of each support at time t1 obtained in step S3 with the displacement at time t2 to obtain the displacement change values ​​in the x direction, y direction, z direction, xz direction tilt change value, and yz direction tilt change value at time t1 and time t2, and then form a matrix in the time domain. Furthermore, the specific implementation method of step S4 includes the following steps: S4.1. Calculate the displacement change in the x-direction at time t1 and time t2. ,in and These are the x-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.2. Calculate the displacement changes in the y-direction at time t1 and time t2. ,in and These are the y-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.3. Calculate the displacement change in the z-direction at time t1 and time t2. ,in and These are the z-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.4. Calculate the change in tilt in the xz direction at time t1 and time t2. ,in and These represent the xz-direction tilt after noise reduction preprocessing at times t1 and t2, respectively. S4.5. Calculate the change in tilt along the yz direction at time t1 and time t2. ,in and These represent the tilt in the yz direction after noise reduction preprocessing at times t1 and t2, respectively. S4.6. Construct the matrix in the time domain; the calculation expression is as follows: ; S5. Using the cross-correlation function, calculate the cross-correlation coefficient between arrays in adjacent time domains from the matrix obtained in step S4 to obtain the trend matrix of the support in the time domain. The cross-correlation function The calculation formula is: ; in, This represents the cross-correlation coefficient across adjacent time domains; Furthermore, the support variation trend matrix in the time domain in step S5 includes the support displacement variation trend matrix and the support tilt variation trend matrix in the time domain. The expression for the support displacement variation trend matrix in the time domain is: ; The expression for the trend matrix of the inclination change of the support in the time domain is: ; S6. Evaluate the condition of the bridge supports based on the trend matrix of the supports in the time domain obtained in step S5.

[0026] Furthermore, when the cross-correlation coefficient u in the third column of the displacement change trend matrix of the support in the time domain tends to be 0 for a long time and there is no regression trend, it indicates that the support void in the Z direction has existed for a long time and the void amount shows a gradual increasing trend. The support may be aging cracked or the support void may be damaged.

[0027] When the cross-correlation coefficient u in the third column of the displacement change trend matrix of the support in the time domain fluctuates around 1, with a fluctuation ratio of 10-20%, it indicates that the support performance is good.

[0028] When the cross-correlation coefficient u in the third column of the displacement change trend matrix of the support in the time domain first tends to 1 and then gradually tends to 0, it indicates that the support has experienced a slippage in the Z direction, and there is a risk of continuous increase.

[0029] When the cross-correlation coefficient u in the third column of the displacement change trend matrix of the support in the time domain first approaches 0 and then gradually approaches 1, it indicates that the support has experienced a release in the Z direction and then tends to stabilize.

[0030] If the cross-correlation coefficients of the first column of the displacement trend matrix of the support in the time domain and the first column of the tilt trend matrix of the support in the time domain both tend to be 0 for a long time and there is no regression trend, it indicates that the support has displacement caused by the tilt of the support in that direction.

[0031] When the cross-correlation coefficient u of the first column of the displacement trend matrix of the support in the time domain and the first column of the tilt trend matrix of the support in the time domain fluctuates around 1, with a fluctuation ratio of 10-20%, it indicates that the support performance is good.

[0032] When the cross-correlation coefficient u of the first column of the displacement trend matrix of the support in the time domain and the first column of the tilt trend matrix of the support in the time domain first tends to 1 and then gradually tends to 0, it indicates that the support has undergone displacement in that direction and there is a risk of continuous increase.

[0033] When the cross-correlation coefficient u of the first column of the displacement trend matrix of the support in the time domain and the first column of the tilt trend matrix of the support in the time domain first approaches 0 and then gradually approaches 1, it indicates that the support has undergone displacement in that direction and then tends to stabilize.

[0034] Similarly, by calculating the cross-correlation coefficient trend of the second column of the displacement trend matrix of the support in the time domain and the second column of the tilt trend matrix of the support in the time domain, the displacement of the support in that direction can be obtained.

[0035] Under normal circumstances, supports are unlikely to experience displacement in the XY directions unless subjected to strong force. By calculating the columns in the matrix, it can be determined whether the support has suffered strong force damage or whether the support has come loose in the Z direction. If strong force damage has occurred, timely repair and replacement are necessary. If the vertical support loosening value is large, an alarm should be triggered immediately.

[0036] Based on the above methods, it is possible not only to determine the over-limit alarm of bearing detachment and the direction of bearing detachment, but also to identify bearing defects.

[0037] Furthermore, the specific installation and monitoring process is as follows: 1. Use expansion bolts to connect the top fixing plate to the beam body, and use expansion bolts to connect the lower fixing base plate.

[0038] 2. A device for synchronously monitoring the three-dimensional displacement and tilt of a bearing is fixed between the bridge bearing and the beam. When the bearing and the beam move vertically, the amount of bearing separation is measured in real time using a separation sensing device. When the bearing moves horizontally or tilts, the tilt and displacement in the horizontal direction can be measured using a tilt measuring device.

[0039] 3. Then, data analysis software is used to analyze the measurement data in real time to obtain the changes in inclination and displacement, and the performance evaluation of the bridge bearings is carried out based on the trend of the changes.

[0040] The key points and areas to be protected in this invention are: Key points: 1. The idea of ​​designing an all-around tilt measuring device by combining the lever principle and the magnetic repulsion principle.

[0041] 2. Design concept of monitoring the support detachment caused by temperature load and vehicle load based on the temperature compensation of fiber optic grating temperature compensation sensor.

[0042] 3. Measurement approach for planar displacement based on tilt angle.

[0043] 4. A method for evaluating the performance of bridge bearings based on the change value of cross-correlation function.

[0044] Protection point: 1. The idea of ​​designing an all-around tilt measuring device by combining the lever principle and the magnetic repulsion principle.

[0045] 2. Design concept of monitoring the support detachment caused by temperature load and vehicle load based on the temperature compensation of fiber optic grating temperature compensation sensor.

[0046] 3. A method for evaluating the performance of bridge bearings based on the change value of cross-correlation function.

[0047] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0048] Although this application has been described above with reference to specific embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of this application. In particular, as long as there is no structural conflict, the features in the specific embodiments disclosed in this application can be combined with each other in any way. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, this application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A device for synchronously monitoring the three-dimensional displacement and tilt of a support, characterized in that, Includes a top fixed plate (1), a detachment sensing rod (2), an upper protective box (3), an inclination measuring device (4), a lower protective box (5), a detachment sensing device (7), a lower fixed base plate (6), and a cross support rod (8). The upper protective box (3) and the lower protective box (5) are arranged vertically. The tilt measuring device (4) is placed inside the upper protective box (3), and the detachment sensing device (7) is placed inside the lower protective box (5). The lower protective box (5) is connected to the lower fixed chassis (6). The tilt measuring device (4) consists of two groups, which are respectively set in the xz direction and yz direction inside the upper protective box (3). The detachment sensing device (7) consists of four groups, which are respectively set in the four apex directions inside the lower protective box (5). The tilt measuring device (4) includes two first cylindrical bodies (4-5) arranged side by side on the bottom plate of the upper protective box (3). Each first cylindrical body (4-5) is provided with a first bottom disk (4-3) and a first magnetic induction plate (4-4). The lower end of the first cylindrical rod (4-2) is connected to the first bottom disk (4-3). The first bottom disk (4-3) is located above the first magnetic induction plate (4-4). The upper surface of the first bottom disk (4-3) and the first magnetic induction plate (4-4) have the same magnetism. The lower surface of the first magnetic induction plate (4-4) is attached with a first fiber optic strain sensor (4-6). The upper ends of the two first cylindrical rods (4-2) are hinged to both ends of the connecting rod (4-1). The middle part of the connecting rod (4-1) is hinged to the support rod (4-7). The lower end of the support rod (4-7) is fixed on the bottom plate of the upper protective box (3). The top fixing plate (1) is installed on the top of the de-emptying sensing rod (2), the de-emptying sensing rod (2) passes through the upper protective box (3) and the cross support rod (8) and is hinged to the de-emptying sensing device (7); The detachment sensing device (7) includes a second cylindrical body (7-5). Each second cylindrical body (7-5) is provided with a second bottom disk (7-3) and a second magnetic sensing plate (7-2). The upper end of the second cylindrical rod (7-1) is hinged to the cross support rod (8). The lower end of the second cylindrical rod (7-1) is connected to the second bottom disk (7-3). The second bottom disk (7-3) is located above the second magnetic sensing plate (7-2). The upper surface of the second bottom disk (7-3) and the second magnetic sensing plate (7-2) have the same magnetism. A second fiber optic strain sensor (7-4) is attached to the lower surface of the second magnetic sensing plate (7-2). The top fixing plate (1) is fixedly connected to the bridge beam, and the lower fixing base plate (6) is fixedly connected to the bridge pier.

2. The device for synchronously monitoring the three-dimensional displacement and tilt of a support according to claim 1, characterized in that, The tilt measuring device (4) also includes a fiber optic grating temperature compensation sensor, which is placed on the outside of the first cylindrical body (4-5) and connected to the first fiber optic grating strain sensor (4-6) via optical fiber.

3. The device for synchronously monitoring the three-dimensional displacement and tilt of a support according to claim 1, characterized in that, The vacancy sensing device (7) also includes a fiber optic grating temperature compensation sensor, which is placed on the outside of the second cylindrical body (7-5) and connected to the second fiber optic grating strain sensor (7-4) via optical fiber.

4. A method for evaluating the detachment of a device for synchronously monitoring the three-dimensional displacement and tilt of a support, implemented based on the device for synchronously monitoring the three-dimensional displacement and tilt of a support as described in any one of claims 1-3, characterized in that... Includes the following steps: S1. For a device for synchronously monitoring the three-dimensional displacement and tilt of the support installed on each bridge pier, the tilt angle measuring device in the xz direction collects the strain data of the fiber optic strain sensor in the xz direction, the tilt angle measuring device in the yz direction collects the strain data of the fiber optic strain sensor in the yz direction, and the four delamination sensing devices collect the fiber optic strain sensor data in the four directions. S2. Based on the data obtained in step S1, calculate the displacement X in the x direction, the displacement Y in the y direction, and the displacement Z in the z direction of the bridge support; S3. Using the wavelet transform principle, the displacements X, Y, and Z of the bridge supports in the x-direction, y-direction, z-direction, xz-direction tilt angle bx, and yz-direction tilt angle by of the bridge supports obtained in step S2 are preprocessed to remove noise interference factors, resulting in the following calculation formula: X1 = XO(X) Where O(X) is the displacement in the x direction caused by external noise interference, and X1 is the displacement of the bridge support in the x direction after preprocessing with wavelet transform. Y1=YO(Y) Where O(Y) is the displacement in the y direction caused by external noise interference, and Y1 is the displacement of the bridge support in the y direction after preprocessing with wavelet transform. Z1 = ZO(Z) Where O(Z) is the displacement in the z direction caused by external noise interference, and Z1 is the displacement of the bridge support in the z direction after wavelet transform preprocessing. bx1 = bx - O(bx) Where O(bx) is the tilt angle in the xz direction caused by external noise interference, and bx1 is the tilt angle in the xz direction after preprocessing with wavelet transform; by1 = by - O(by) Where O(by) is the tilt angle in the yz direction caused by external noise interference, and by1 is the tilt angle in the yz direction after preprocessing with wavelet transform. S4. Compare the displacement of each support at time t1 obtained in step S3 with the displacement at time t2 to obtain the displacement change values ​​in the x direction, y direction, z direction, xz direction tilt change value, and yz direction tilt change value at time t1 and time t2, and then form a matrix in the time domain. S5. Using the cross-correlation function, calculate the cross-correlation coefficient between arrays in adjacent time domains from the matrix obtained in step S4 to obtain the trend matrix of the support in the time domain. The cross-correlation function The calculation formula is: )= in, This represents the cross-correlation coefficient across adjacent time domains; S6. Evaluate the condition of the bridge supports based on the trend matrix of the supports in the time domain obtained in step S5.

5. The method for evaluating the voiding of a device for synchronously monitoring the three-dimensional displacement and tilt of a support according to claim 4, characterized in that, The specific implementation method of step S2 includes the following steps: S2.

1. The formula for calculating the displacement X of a bridge support in the x-direction is: X = m(1 - cosbx) Where m is the length of the connecting rod of the tilt measuring device in the xz direction, and bx is the tilt angle in the xz direction; bx is obtained by fitting data collected by the fiber optic strain sensor in the tilt measurement device in the xz direction. The calculation expression is: in, The first data fitting coefficient is... The fitting coefficients for the second data are... This is the first data from the fiber optic strain sensor inside the tilt measurement device in the xz direction. The second data is from the fiber optic strain sensor inside the tilt measurement device in the xz direction; S2.

2. The formula for calculating the displacement Y of a bridge support in the y-direction is: Y=n(1-coxby) Where n is the length of the connecting rod of the tilt measuring device in the yz direction, and by is the tilt angle in the yz direction; The value of 'by' is obtained by fitting data collected from fiber optic strain sensors in the tilt measurement device along the yz direction. The calculation expression is as follows: in, The fitting coefficients for the third data are... The fourth data fitting coefficient, This is the third data from the fiber optic strain sensor inside the tilt measurement device in the yz direction. This is the fourth data point from the fiber optic strain sensor inside the tilt measurement device in the yz direction.

6. The method for evaluating the voiding of a device for synchronously monitoring the three-dimensional displacement and tilt of a support according to claim 5, characterized in that, The specific implementation method of step S4 includes the following steps: S4.

1. Calculate the displacement change in the x-direction at time t1 and time t2. ,in and These are the x-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.

2. Calculate the displacement changes in the y-direction at time t1 and time t2. ,in and These are the y-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.

3. Calculate the displacement change in the z-direction at time t1 and time t2. ,in and These are the z-direction displacements after noise reduction preprocessing at times t1 and t2, respectively. S4.

4. Calculate the change in tilt in the xz direction at time t1 and time t2. ,in and These represent the xz-direction tilt after noise reduction preprocessing at times t1 and t2, respectively. S4.

5. Calculate the change in tilt along the yz direction at time t1 and time t2. ,in and These represent the tilt in the yz direction after noise reduction preprocessing at times t1 and t2, respectively. S4.

6. Construct the matrix in the time domain; the calculation expression is as follows: 。 7. The method for evaluating the voiding of a device for synchronously monitoring the three-dimensional displacement and tilt of a support according to claim 6, characterized in that, The support variation trend matrix in the time domain in step S5 includes the support displacement variation trend matrix and the support tilt variation trend matrix in the time domain. The expression for the support displacement variation trend matrix in the time domain is: The expression for the trend matrix of the inclination change of the support in the time domain is: 。

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