Method and device for monitoring internal force of shock insulation rubber support

Abstract

The invention relates to the technical field of civil engineering structures, in particular to a seismic isolation rubber support internal force monitoring method and device. The seismic isolation rubber support internal force monitoring method comprises the steps that pressure data of at least four monitoring point positions are received, and the pressure difference between two monitoring point positions symmetrical relative to the axis of a seismic isolation rubber support is calculated; and the vertical force and the shearing force of the shock insulation rubber support are calculated through fitting according to the relationship between the pressure difference and the shearing force. According to the method and the device for monitoring the internal force of the shock insulation rubber support, the shock insulation rubber support can be installed together with the support according to the installation condition of the shock insulation rubber support, the internal force of the shock insulation rubber support can be monitored in real time for a long time, and then the working state of the shock insulation rubber support can be monitored, so that the shock insulation rubber support can be maintained conveniently, and the shock insulation function of the shock insulation rubber support is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of seismic isolation bearing monitoring, and in particular to a method and device for monitoring the internal force of a seismic isolation rubber bearing. Background Art

[0002] Earthquakes are serious natural disasters that cause immense damage to buildings and infrastructure. Traditional earthquake-resistant design relies primarily on the structure's ability to withstand strong earthquakes, but this approach often fails to effectively withstand the impact of strong earthquakes. Therefore, seismic isolation technology has emerged as an effective earthquake-resistant measure. Seismic isolation rubber bearings significantly reduce a building's seismic response by extending the structure's natural vibration period and reducing the transfer of seismic energy, thereby protecting the structure.

[0003] Due to their excellent isolation performance and cost-effectiveness, seismic isolation rubber bearings have become an indispensable component of modern earthquake-resistant structures. Currently, they are widely used in buildings, bridges, subways, and other engineering projects in earthquake-prone areas. With the acceleration of urbanization and the increasing demand for building seismic performance, the application market for seismic isolation rubber bearings is also expanding. By installing an isolation layer between the foundation or substructure and the superstructure of a building, they can isolate the energy from environmental vibrations such as earthquakes or subway trains.

[0004] Seismic isolation rubber bearings are a key component in the seismic resistance systems of structures such as buildings and bridges. They dissipate a significant amount of energy and are therefore among the most susceptible to damage. If early damage is not detected promptly, it can lead to sudden structural failure, resulting in serious consequences. Monitoring the internal forces of seismic isolation rubber bearings helps understand their performance and operating conditions, promptly detect abnormalities, and assess their health. This monitoring plays a crucial role in improving the design of seismic isolation structures, enhancing the design level of seismic isolation bearings, and promoting the development of seismic isolation technology.

[0005] Measuring the internal forces of seismic isolation rubber bearings is very difficult due to the highly nonlinear and complex mechanical behavior of rubber materials (especially hyperelasticity, viscoelasticity, and possible anisotropy under large deformations) and the very large bearing capacity during operation. Summary of the Invention

[0006] The purpose of the present invention includes providing a method and device for monitoring the internal force of a seismic isolation rubber bearing, which can be installed together with the bearing according to the installation conditions of the seismic isolation rubber bearing, and can monitor the internal force of the seismic isolation rubber bearing in real time for a long time, and then can monitor the working status of the seismic isolation rubber bearing to facilitate its maintenance and ensure its seismic isolation function.

[0007] The embodiments of the present invention can be implemented as follows: In a first aspect, the present invention provides a method for monitoring the internal force of a seismic isolation rubber bearing, comprising: receiving pressure data of at least four monitoring points and calculating the pressure difference between two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing; The vertical force and shear force of the seismic isolation rubber bearing are calculated based on the relationship between pressure difference and shear force.

[0008] In an optional embodiment, the step of calculating the vertical force of the seismic isolation rubber bearing by fitting the relationship between the pressure difference and the shear force includes: According to the pressure data of the four monitoring points, the average pressure of the four monitoring points is calculated; Calculate the vertical force of the seismic isolation rubber bearing: ; Where: FN is the vertical force of the seismic isolation rubber bearing, M is the correction coefficient obtained by calibration, is the surface area of the sensor at the monitoring point, and S is the surface area of the isolation support.

[0009] In an optional embodiment, the step of calculating the shear force of the seismic isolation rubber bearing by fitting the relationship between the pressure difference and the shear force includes: Determine the direction of the shear force θ; Calculate the distance between the projections of two monitoring points symmetrical with respect to the axis of the isolation rubber bearing in the shear force direction: ; Calculate the projection distance of the other two monitoring points symmetrical with respect to the axis of the isolation rubber bearing in the shear force direction: ; according to The shear internal force of the support is calculated by fitting the pressure difference of the four monitoring points; Among them, A is the distance between the four monitoring points and the axis of the seismic isolation rubber bearing.

[0010] In an optional embodiment, the step of determining the direction θ of the shear force comprises: A three-dimensional coordinate system is established with the position of one end of the telescopic rod as the origin O, and the three coordinates of the other end E of the telescopic rod are (A, C, G); Receive the tilt angle α of the follow-up telescopic rod relative to the X-axis and the tilt angle β relative to the Y-axis output by the angle sensor; The length of the telescopic rod is L OE , the projection of the telescopic rod in the XOZ plane is OD, the projection of the telescopic rod in the YOZ plane is OF, and the projection of the telescopic rod in the XOY plane is OB, then: Length of BE: ; The length of line segment AD=BE, OA: ; The length of line segment AB=CF, AD is: ; The angle θ of the shear force direction OB can be expressed as: .

[0011] In a second aspect, the present invention provides a seismic isolation rubber bearing internal force monitoring device for implementing the above-mentioned seismic isolation rubber bearing internal force monitoring method, the seismic isolation rubber bearing internal force monitoring device includes a pressure monitoring component and a bearing deformation monitoring component; The pressure monitoring assembly is connected to the sealing plate of the seismic isolation rubber bearing and is used to monitor the pressure data of at least four monitoring points, the four monitoring points are arranged at intervals around the axis of the seismic isolation rubber bearing, and the four monitoring points are symmetrical with respect to the axis of the seismic isolation rubber bearing; The bearing deformation monitoring assembly is located between the two sealing plates of the seismic isolation rubber bearing, and its two ends are respectively connected to the two sealing plates. The bearing deformation monitoring assembly is used to move with the seismic isolation rubber bearing to monitor the direction of the shear force of the seismic isolation rubber bearing.

[0012] In an optional embodiment, the pressure monitoring assembly includes at least four pressure sensors, at least one pressure sensor is installed corresponding to each monitoring point, and the distances from the four monitoring points to the axis of the seismic isolation rubber bearing are the same.

[0013] In an optional embodiment, a temperature sensor is provided on the connection surface between the sealing plate and the rubber seat of the seismic isolation rubber bearing.

[0014] In an optional embodiment, the support deformation monitoring assembly includes a first connecting seat, a second connecting seat, a follow-up telescopic rod, and an angle sensor; The first connecting seat and the second connecting seat are respectively connected to the two sealing plates; the two ends of the follow-up telescopic rod are respectively hinged to the first connecting seat and the second connecting seat; the angle sensor is connected to the follow-up telescopic rod and is used to detect the inclination angle of the follow-up telescopic rod.

[0015] In an optional embodiment, the bearing deformation monitoring assembly is embedded in the mounting hole inside the seismic isolation rubber bearing.

[0016] In an optional embodiment, the bearing deformation monitoring assembly is placed on the periphery of the rubber seat of the seismic isolation rubber bearing.

[0017] The beneficial effects of the method and device for monitoring the internal force of a seismic isolation rubber bearing provided by the embodiments of the present invention include: The seismic isolation rubber bearing internal force monitoring method includes: receiving pressure data from at least four monitoring points, calculating the pressure difference between two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing; and calculating the vertical force and shear force of the seismic isolation rubber bearing based on the relationship between the pressure difference and the shear force. The seismic isolation rubber bearing internal force monitoring method and device can be installed with the seismic isolation rubber bearing according to the installation conditions of the seismic isolation rubber bearing, and can monitor the internal force of the seismic isolation rubber bearing in real time over a long period of time, thereby monitoring the working status of the seismic isolation rubber bearing to facilitate its maintenance and ensure its seismic isolation function. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the distribution of four pressure sensors provided in this embodiment in a rectangular coordinate system; Figure 2 A schematic diagram of a three-dimensional coordinate system provided in this embodiment, with the position of one end of the follow-up telescopic rod as the origin O; Figure 3 A schematic structural diagram of the seismic isolation rubber bearing provided in this embodiment from a first perspective; Figure 4 A schematic structural diagram of the seismic isolation rubber bearing provided in this embodiment from a second viewing angle; Figure 5 A cross-sectional view of the seismic isolation rubber bearing provided in this embodiment; Figure 6 A schematic diagram of the structure of the support deformation monitoring component of the seismic isolation rubber support provided in this embodiment, which is located inside the rubber support; Figure 7 for Figure 6 Local schematic diagram at point M in the middle.

[0020] Icons: 100-seismic isolation rubber bearing; 110-rubber seat; 120-sealing plate; 121-upper sealing plate; 122-lower sealing plate; 200-seismic isolation rubber bearing internal force monitoring device; 210-pressure monitoring assembly; 220-support deformation monitoring assembly; 211-pressure sensor; 221-first connecting seat; 222-second connecting seat; 223-follow-up telescopic rod. DETAILED DESCRIPTION

[0021] Earthquakes are serious natural disasters that cause immense damage to buildings and infrastructure. Traditional earthquake-resistant design relies primarily on the structure's ability to withstand strong earthquakes, but this approach often fails to effectively withstand the impact of strong earthquakes. Therefore, seismic isolation technology has emerged as an effective earthquake-resistant measure. Seismic isolation rubber bearings significantly reduce a building's seismic response by extending the structure's natural vibration period and reducing the transfer of seismic energy, thereby protecting the structure.

[0022] Due to their excellent isolation performance and cost-effectiveness, seismic isolation rubber bearings have become an indispensable component of modern earthquake-resistant structures. Currently, they are widely used in buildings, bridges, subways, and other engineering projects in earthquake-prone areas. With the acceleration of urbanization and the increasing demand for building seismic performance, the application market for seismic isolation rubber bearings is also expanding. By installing an isolation layer between the foundation or substructure and the superstructure of a building, they can isolate the energy from environmental vibrations such as earthquakes or subway trains.

[0023] In seismic systems such as buildings and bridges, rubber isolation bearings dissipate a significant amount of energy and are among the most susceptible to damage. If early damage is not detected, it can lead to sudden structural failure, resulting in serious consequences. Monitoring the internal forces of rubber isolation bearings helps understand their performance and operating conditions, promptly detect abnormalities, and assess their health. This monitoring plays a crucial role in improving the design of seismic isolation structures, enhancing the design level of isolation bearings, and promoting the development of seismic isolation technology.

[0024] However, due to the highly nonlinear and complex mechanical behavior of rubber materials (especially hyperelasticity, viscoelasticity and possible anisotropy under large deformation), and the very large bearing capacity during operation, it is very difficult to measure the internal forces of seismic isolation rubber bearings.

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0028] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0029] In addition, the terms "first", "second", etc., if used, are merely used to distinguish and describe, and should not be understood as indicating or implying relative importance.

[0030] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0031] The inventors have found through research that, at present, there is no effective means for in-situ monitoring of seismic isolation devices, and the commonly used method for studying and testing the performance of seismic isolation bearings is to use a testing machine to conduct a load test. However, in engineering applications, due to the influence of the bearing use environment, detection accuracy and other issues, the force and deformation monitoring methods used in the load test cannot be installed and used together with the bearing, and in actual use, the force parameters of the bearing cannot be given like a testing machine. When the bearing has been in service for a period of time, or when the performance test or damage assessment of the bearing in service is required, the bearing needs to be removed from the structure, which is simply impossible for certain special structures or special situations, and even if it can be removed, it is time-consuming and labor-intensive. Therefore, it is necessary to design a monitoring method that can be installed with the bearing according to the bearing installation conditions, and can monitor the force and deformation of the bearing in real time over a long period of time.

[0032] Numerous researchers have conducted research on the detection and monitoring of parameters such as stress, deformation, and damage in seismic isolation bearings, and have proposed various detection and monitoring methods. These monitoring methods can be broadly categorized into two types: contact measurement and non-contact measurement. Contact measurement involves installing force sensors and displacement sensors on the isolation bearings to directly measure the bearing's stress and deformation data. Another contact measurement approach involves deploying accelerometers or velocity sensors on or near the bearings, analyzing the sensor data to determine the bearing's stress and deformation parameters. Non-contact measurement involves installing ultrasonic or piezoelectric sensors near the isolation bearings. Deformation of the bearings causes changes in the ultrasonic signals. By monitoring these ultrasonic signals and processing and analyzing them, characteristic information about the bearings is extracted, indirectly determining the bearing's state parameters. Another non-contact measurement approach involves installing cameras near the bearings and using visual recognition methods to detect bearing displacement. However, these approaches suffer from limited measurement ranges and low accuracy, remaining limited to experimental research and inaccessible to practical application.

[0033] For the reasons above, please refer to Figure 1-Figure 7 This embodiment provides a method for monitoring the internal force of a seismic isolation rubber bearing 100, comprising: Receive pressure data of at least four monitoring points, and calculate the pressure difference between two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing 100; Figure 1 As shown, the four monitoring points are Figure 1 Mark 1, mark 2, mark 3 and mark 4 in the rectangular coordinate system shown, wherein the axis of the seismic isolation rubber bearing 100 passes through the coordinate origin, and mark 1 is symmetrical to mark 3, and mark 2 is symmetrical to mark 4; The vertical force and shear force of the seismic isolation rubber bearing 100 are calculated based on the relationship between the pressure difference and the shear force.

[0034] The method for monitoring the internal force of the seismic isolation rubber bearing 100 includes: receiving pressure data from at least four monitoring points, calculating the pressure difference between two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing 100; and calculating the vertical force and shear force of the seismic isolation rubber bearing 100 based on the relationship between the pressure difference and the shear force. The method and device for monitoring the internal force of the seismic isolation rubber bearing 100 can be installed with the seismic isolation rubber bearing 100 according to the installation conditions of the seismic isolation rubber bearing 100, and can monitor the internal force of the seismic isolation rubber bearing 100 in real time over a long period of time, thereby monitoring the working status of the seismic isolation rubber bearing 100 to facilitate maintenance and ensure its seismic isolation function.

[0035] It should be noted that the seismic isolation rubber bearing 100 is a structural component with low horizontal stiffness and high vertical stiffness. It needs to bear the vertical load of the building superstructure to ensure the stability of the structure. When an earthquake occurs, the vertical movement of the ground will cause changes in the vertical load of the bearing, and the horizontal seismic waves will cause shear deformation of the bearing. The seismic isolation rubber bearing 100, due to its low stiffness in the horizontal direction, can allow large horizontal deformation, thereby effectively dissipating earthquake energy. Real-time monitoring of the vertical and shear internal forces of the seismic isolation bearing can be used to reinforce or repair the bearing in time before the bearing capacity or isolation effect decreases, thereby improving the reliability of the seismic isolation system. In addition, through long-term monitoring of the internal forces of the bearing, the degradation trend of its bearing capacity and isolation performance can be revealed, and the need for maintenance and replacement can be predicted to avoid isolation failure due to damage to the device. The monitoring data can be used to further analyze and study the performance of the seismic isolation bearing under actual working conditions, providing a scientific basis for future design and improvement. Proper monitoring and maintenance can extend the service life of the seismic isolation bearing, reduce the frequency of replacement, and thus save costs.

[0036] Further, please refer to Figure 1-Figure 7 In this embodiment, the step of calculating the vertical force of the seismic isolation rubber bearing 100 by fitting the relationship between the pressure difference and the shear force includes: According to the pressure data of the four monitoring points, the average pressure of the four monitoring points is calculated; Calculate the vertical force of the seismic isolation rubber bearing 100: ; Where: FN is the vertical force of the seismic isolation rubber bearing 100, M is the correction coefficient obtained by calibration, is the surface area of the sensor at the monitoring point, and S is the surface area of the isolation support.

[0037] The step of calculating the shear force of the seismic isolation rubber bearing 100 by fitting the relationship between the pressure difference and the shear force includes: Determine the direction of the shear force θ; Calculate the distance between the projections of two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing 100 in the shear force direction: ; Calculate the projection distance of the other two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing 100 in the shear force direction: ; according to The shear internal force of the support is calculated by fitting the pressure difference of the four monitoring points; Wherein, A is the distance between the four monitoring points and the axis of the seismic isolation rubber bearing 100 .

[0038] Further, please refer to Figure 1-Figure 7 In this embodiment, the step of determining the direction θ of the shear force includes: A three-dimensional coordinate system is established with the position of one end of the follow-up telescopic rod 223 as the origin O (e.g. Figure 2 As shown), the three coordinates of the other end E of the follow-up telescopic rod 223 are (A, C, G); Receive the tilt angle α of the follow-up telescopic rod 223 relative to the X-axis and the tilt angle β relative to the Y-axis output by the angle sensor; The length of the follow-up telescopic rod 223 is L OE , the projection of the follow-up telescopic rod 223 in the XOZ plane is OD, the projection of the follow-up telescopic rod 223 in the YOZ plane is OF, and the projection of the follow-up telescopic rod 223 in the XOY plane is OB, then: Length of BE: ; The length of line segment AD=BE, OA: ; The length of line segment AB=CF, AD is: ; The angle θ of the shear force direction OB can be expressed as: .

[0039] Based on the above, please refer to Figure 1-Figure 7 This embodiment further provides a seismic isolation rubber bearing internal force monitoring device 200 for implementing the above-mentioned seismic isolation rubber bearing 100 internal force monitoring method. The seismic isolation rubber bearing internal force monitoring device 200 includes a pressure monitoring component 210 and a bearing deformation monitoring component 220. The pressure monitoring assembly 210 is connected to the sealing plate 120 of the seismic isolation rubber bearing 100 and is used to monitor the pressure data of at least four monitoring points. The four monitoring points are spaced apart around the axis of the seismic isolation rubber bearing 100, and the four monitoring points are symmetrical with respect to the axis of the seismic isolation rubber bearing 100. The support deformation monitoring assembly 220 is located between the two sealing plates 120 of the seismic isolation rubber bearing 100, and its two ends are respectively connected to the two sealing plates 120. The support deformation monitoring assembly 220 is used to move with the seismic isolation rubber bearing 100 to monitor the direction of the shear force of the seismic isolation rubber bearing 100.

[0040] In this embodiment, the pressure monitoring assembly 210 includes at least four pressure sensors 211. Each monitoring point is equipped with at least one pressure sensor 211. The four monitoring points are located at the same distance from the axis of the seismic isolation rubber bearing 100. Furthermore, a temperature sensor is provided on the connection surface between the sealing plate 120 and the rubber seat 110 of the seismic isolation rubber bearing 100.

[0041] When configuring the support deformation monitoring assembly 220, the support deformation monitoring assembly 220 includes a first connecting seat 221, a second connecting seat 222, a follow-up telescopic rod 223 and an angle sensor; The first connecting seat 221 and the second connecting seat 222 are respectively connected to the two sealing plates 120; the two ends of the follow-up telescopic rod 223 are respectively hinged to the first connecting seat 221 and the second connecting seat 222; the angle sensor is connected to the follow-up telescopic rod 223 and is used to detect the inclination angle of the follow-up telescopic rod 223.

[0042] When installing the support deformation monitoring assembly 220, if Figure 3 and Figure 4 As shown, the support deformation monitoring assembly 220 is placed on the periphery of the rubber seat 110 of the seismic isolation rubber support 100; or, as shown Figure 6 and Figure 7 As shown, the bearing deformation monitoring assembly 220 is embedded in the mounting hole inside the seismic isolation rubber bearing 100 .

[0043] Based on the above, please refer to Figure 1-Figure 7 The steps of implementing the internal force monitoring method of the seismic isolation rubber bearing 100 using the above-mentioned seismic isolation rubber bearing internal force monitoring device 200 are as follows: Take the following structure of the seismic isolation rubber bearing 100 as an example: The seismic isolation rubber bearing 100 is composed of an upper connecting plate, an upper sealing plate 121, multiple layers of rubber, a stiffening steel plate, a protective layer of rubber, a lower sealing plate 122 and a lower connecting plate; wherein, the two sealing plates 120 are the upper sealing plate 121 and the lower sealing plate 122, and the multiple layers of rubber and the stiffening steel plate constitute the multi-layer rubber seat 110, which bears the weight and horizontal displacement of the building; based on the aforementioned structure, a lead core can also be set inside the seismic isolation rubber bearing 100; when an earthquake occurs, the lead core absorbs energy through plastic deformation; after the earthquake, the lead core relies on dynamic recovery and recrystallization processes, as well as the shear tension of the rubber, to automatically restore the building to its original position. Depending on the type of lead core and the requirements of the bridge, the seismic isolation rubber bearing 100 can adopt different laminated structures, manufacturing processes and formula designs to meet the required vertical stiffness, lateral deformation, damping, durability, overturning lift-off and other performance requirements.

[0044] The seismic isolation rubber bearing internal force monitoring device 200 is designed to measure the internal force of the seismic isolation rubber bearing 100. Based on this, four blind holes are set on one of the sealing plates 120 of the seismic isolation rubber bearing 100. Four miniature pressure sensors 211 are installed in the blind holes, and the upper surface of the pressure sensors 211 is flush with the surface of the sealing plate 120. When the seismic isolation rubber bearing 100 is manufactured, the sealing plate 120 and its built-in pressure sensors 211 are vulcanized and bonded to the rubber layer together. At this time, the pressure sensors 211 are reliably bonded to the rubber layer. It should be noted that this embodiment uses four pressure sensors 211 as an example. These four pressure sensors 211 are placed in the lower sealing plate 120, and a temperature sensor is embedded in the surface of the sealing plate 120. The measured temperature data is used to correct the results of the internal force monitoring calculation. In other embodiments of the present invention, a larger number of pressure sensors 211 may be configured. To accommodate this, the number of blind holes in the sealing plate 120 needs to be adjusted accordingly. Furthermore, more sensors will provide more accurate measurement results and provide sensor redundancy. Please refer to Figure 1 The four pressure sensors 211 are distributed in the rectangular coordinate system of the sealing plate 120 plane. The four pressure sensors 211 are respectively the first pressure sensor 211, the second pressure sensor 211, the third pressure sensor 211 and the fourth pressure sensor 211; among them, the first pressure sensor 211 and the third pressure sensor 211 are arranged symmetrically with respect to the origin, and the second pressure sensor 211 and the fourth pressure sensor 211 are arranged symmetrically with respect to the origin, and the origin is the center point of the sealing plate 120, and the axis of the rubber seat 110 passes through the center point.

[0045] When the seismic isolation rubber bearing 100 is subjected to shear force, the internal force measurement is relatively complicated; When the seismic isolation rubber bearing 100 is subjected to shear force, the force on each pressure sensor 211 will change due to the expansion, tension and compression deformation of the rubber. Under actual seismic vibration conditions, the direction of the shear force is uncertain. For example, when the lower sealing plate 122 of the seismic isolation rubber bearing 100 is relatively fixed and its upper sealing plate 121 is subjected to shear force along the X-axis, according to the point of action and direction of the shear force, the second pressure sensor 211 will be subjected to more pressure, while the pressure on the fourth sensor will be reduced accordingly. At this time, a pressure difference is formed between the second pressure sensor 211 and the fourth pressure sensor 211. The line connecting the first and third pressure sensors 211 passes through the origin and is perpendicular to the direction of the shear force. Ideally, the readings of the first and third pressure sensors 211 should be very close, meaning there is no pressure difference. The shear force acting on the seismic isolation rubber bearing 100 can be calculated by calculating the pressure difference between the second and fourth pressure sensors 211, and then fitting the relationship between the pressure difference and shear force obtained through prior calibration experiments (this relationship is related to the sensor's center-to-center distance, the rubber material, and other factors) to calculate the bearing's shear force and vertical force.

[0046] However, when shear forces act on the support in any direction, the four pressure sensors 211, due to their different distribution locations, will produce different pressure values. Since the center distances of the first and third pressure sensors 211, and the center distances of the second and fourth pressure sensors 211, are the same, the projections of the first and third pressure sensors 211, 211, and the projections of the second and fourth pressure sensors 211, 211, in the direction of the shear force are at different distances from the origin. Due to the complexity of rubber's constitutive relationship (stress-strain relationship), the magnitude of the shear force calculated from the pressure difference of the pressure sensors 211 is related to the distance between the sensors and the origin. Therefore, the distance between the pressure sensors 211 and the origin must be calculated based on the measured direction of the shear force, θ.

[0047] In order to measure the direction of the lateral shear force, the support deformation monitoring assembly 220 can be used and installed in the installation hole of the rubber seat 110, or the support deformation monitoring assembly 220 can be placed on the periphery of the rubber seat 110. The specific method is as follows: the first connecting seat 221 and the second connecting seat 222 are respectively installed in the corresponding positioning holes of the upper and lower sealing plates 122 (or in the connecting plate), and then the two ends of the follow-up telescopic rod 223 equipped with the angle sensor are connected to the first connecting seat 221 and the second connecting seat 222; It should be noted that in order to make the two ends of the follow-up telescopic rod 223 hinged to the first connecting seat 221 and the second connecting seat 222 respectively, a joint bearing or a universal joint can be set at the connection; and when configuring the follow-up telescopic rod 223, it can adopt a telescopic rod structure composed of more than two sections of circular tubes; and when installing an angle sensor in the aforementioned telescopic rod structure, a sensor that can measure two-axis or three-axis angles can be fixedly installed in the circular tube constituting the telescopic rod structure, such as: a MEMS inclinometer, a MEMS accelerometer or an angle encoder, etc. At this time, if the vibration isolation rubber bearing is subjected to vertical force and causes vertical deformation, the follower telescopic rod 223 can freely extend and retract to adjust the length, and the angle sensor value remains unchanged at this time; when the vibration isolation rubber bearing 100 is subjected to shear force, the vibration isolation rubber bearing 100 undergoes shear deformation, and the relative movement of the two sealing plates 120 causes the two joint bearings to move horizontally, and the follower telescopic rod 223 will also tilt, thereby forming a follow-up movement. Its built-in angle sensor can measure the shear deformation direction of the bearing, which is the direction of the shear force.

[0048] When the support undergoes shear deformation, the telescopic rod tilts accordingly. Based on this, a three-dimensional coordinate system is established with the position of one end of the follower telescopic rod 223 as the origin O. The three coordinates of the other end E of the follower telescopic rod 223 are (A, C, G); Receive the tilt angle α of the follow-up telescopic rod 223 relative to the X-axis and the tilt angle β relative to the Y-axis output by the angle sensor; The length of the follow-up telescopic rod 223 is L OE , the projection of the follow-up telescopic rod 223 in the XOZ plane is OD, the projection of the follow-up telescopic rod 223 in the YOZ plane is OF, and the projection of the follow-up telescopic rod 223 in the XOY plane is OB, then: Length of BE: ; The length of line segment AD=BE, OA: ; The length of line segment AB=CF, AD is: ; The angle θ of the shear force direction OB can be expressed as: .

[0049] The purpose of measuring the direction of shear force: According to the above content, it can be seen that during service, the seismic isolation rubber bearing 100 is subjected to the gravity of the superstructure and has a preload force. At this time, without considering the measurement error and the distribution difference of the rubber, it can be assumed that the values of the first pressure sensor 211, the second pressure sensor 211, the third pressure sensor 211 and the fourth pressure sensor 211 are the same. When the seismic isolation rubber bearing 100 is subjected to shear force, two symmetrical pressure sensors among the first pressure sensor 211, the second pressure sensor 211, the third pressure sensor 211 and the fourth pressure sensor 211 will produce a pressure difference. The pressure difference is not only related to the shear force exerted on the seismic isolation rubber bearing 100, but also related to the projection distance of the pressure sensors 211 in the direction of the shear force. Since the stress-strain relationship of the rubber material is complex, when the projection distances of the two pairs of pressure sensors 211 in the direction of the shear force are different, there is no clear correspondence between the changes in their pressure differences. Therefore, the direction of the shear force cannot be obtained by numerical calculation using only the four pressure sensors 211. At this time, it is necessary to use the above-mentioned bearing deformation monitoring component 220 to calculate the direction of the shear force in order to more accurately measure the force applied to the bearing.

[0050] After determining the direction of the shear force based on the above steps, that is, determine The shear force on the rubber isolation bearing can be calculated. Specifically, the distance between the four pressure sensors 211 and the coordinate origin is A, and the distance between the projections of the first pressure sensor 211 and the third pressure sensor 211 in any shear force direction is: ; The distance between the projections of the second pressure sensor 211 and the fourth pressure sensor 211 in any shear force direction is: ; according to The pressure difference between the four monitoring points can be used to fit and calculate the shear internal force of the support; According to the above distance 、 The difference between the values of the four pressure sensors 211 can be used to fit and calculate the shear internal force of the support.

[0051] When subjected to shearing action, the vertical force distribution inside the seismic isolation rubber bearing 100 is not uniform. Therefore, the vertical force it is subjected to can be calculated using the average value of the pressure values measured by the four pressure sensors 211. Specifically, the calculation formula is as follows: ; Where: FN is the vertical force of the seismic isolation rubber bearing 100, M is the correction coefficient obtained by calibration, is the average pressure of the four monitoring points, S1 is the surface area of the sensor at the monitoring point, and S is the surface area of the isolation support.

[0052] The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or replacements that can be easily conceived by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A method for monitoring the internal force of a seismic isolation rubber bearing, characterized in that: include: receiving pressure data of at least four monitoring points, and calculating a pressure difference between two of the monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing; The vertical force and shear force of the seismic isolation rubber bearing are calculated based on the relationship between the pressure difference and the shear force.

2. The method for monitoring internal force of a seismic isolation rubber bearing according to claim 1, characterized in that: The step of calculating the vertical force of the seismic isolation rubber bearing by fitting the relationship between the pressure difference and the shear force includes: Calculating the average pressure of the four monitoring points based on the pressure data of the four monitoring points; Calculate the vertical force of the seismic isolation rubber bearing: ； Where: FN is the vertical force of the seismic isolation rubber bearing, M is the correction coefficient obtained by calibration, is the average value of the pressure at the four monitoring points, S1 is the surface area of the sensor at the monitoring point, and S is the surface area of the seismic isolation support.

3. The method for monitoring internal force of a seismic isolation rubber bearing according to claim 1, characterized in that: The step of calculating the shear force of the seismic isolation rubber bearing by fitting the relationship between the pressure difference and the shear force comprises: Determine the direction of the shear force θ; Calculate the distance between the projections of two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing in the shear force direction: ； Calculate the distance between the projections of the other two monitoring points symmetrical with respect to the axis of the seismic isolation rubber bearing in the shear force direction: ； according to The shear internal force of the support is calculated by fitting the pressure difference between the four monitoring points; Wherein, A is the distance between the four monitoring points and the axis of the seismic isolation rubber bearing.

4. The method for monitoring internal force of a seismic isolation rubber bearing according to claim 3, characterized in that: The step of determining the direction θ of the shear force comprises: A three-dimensional coordinate system is established with the position of one end of the follow-up telescopic rod as the origin O, and the three coordinates of the other end E of the follow-up telescopic rod are (A, C, G); receiving an inclination angle α of the follower telescopic rod relative to the X-axis and an inclination angle β relative to the Y-axis outputted by an angle sensor; The length of the follow-up telescopic rod is L OE , the projection of the follow-up telescopic rod in the XOZ plane is OD, the projection of the follow-up telescopic rod in the YOZ plane is OF, and the projection of the follow-up telescopic rod in the XOY plane is OB, then: Length of BE: ； The length of line segment AD=BE, OA: ； The length of line segment AB=CF, AD is: ； The angle θ of the shear force direction OB can be expressed as: 。 5. A seismic isolation rubber bearing internal force monitoring device, used to implement the seismic isolation rubber bearing internal force monitoring method according to any one of claims 1 to 4, characterized in that: The seismic isolation rubber bearing internal force monitoring device includes a pressure monitoring component and a bearing deformation monitoring component; The pressure monitoring assembly is connected to the sealing plate of the seismic isolation rubber bearing and is used to monitor the pressure data of at least four monitoring points, wherein the four monitoring points are arranged at intervals around the axis of the seismic isolation rubber bearing, and the four monitoring points are symmetrical with respect to the axis of the seismic isolation rubber bearing; The support deformation monitoring assembly is located between the two sealing plates of the seismic isolation rubber bearing, and its two ends are respectively connected to the two sealing plates. The support deformation monitoring assembly is used to move with the seismic isolation rubber bearing to monitor the direction of the shear force of the seismic isolation rubber bearing.

6. The seismic isolation rubber bearing internal force monitoring device according to claim 5, characterized in that: The pressure monitoring assembly includes at least four pressure sensors, at least one pressure sensor is installed corresponding to each monitoring point, and the distances between the four monitoring points and the axis of the seismic isolation rubber bearing are the same.

7. The seismic isolation rubber bearing internal force monitoring device according to claim 5, characterized in that: A temperature sensor is provided on the connection surface between the sealing plate and the rubber seat of the seismic isolation rubber support.

8. The seismic isolation rubber bearing internal force monitoring device according to claim 5, characterized in that: The support deformation monitoring assembly includes a first connecting seat, a second connecting seat, a follow-up telescopic rod and an angle sensor; The first connecting seat and the second connecting seat are respectively connected to the two sealing plates; the two ends of the follow-up telescopic rod are respectively hinged to the first connecting seat and the second connecting seat; the angle sensor is connected to the follow-up telescopic rod and is used to detect the inclination angle of the follow-up telescopic rod.

9. The seismic isolation rubber bearing internal force monitoring device according to claim 8, characterized in that: The support deformation monitoring component is embedded in the mounting hole inside the seismic isolation rubber support.

10. The seismic isolation rubber bearing internal force monitoring device according to claim 8, characterized in that: The support deformation monitoring assembly is placed on the outer periphery of the rubber seat of the seismic isolation rubber support.

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