An apparatus and method for measuring the working shear force of shear-type seismic energy dissipators.

Abstract

This invention discloses a device and method for measuring the working shear force of a shear-type seismic energy dissipator, belonging to the field of engineering technology. The device includes a top plate, a bottom plate, multiple vertical web plates, multiple inclined web plate units, and a displacement measuring device. The bottom plate is connected to the end plate of the shear-type seismic energy dissipator to be measured for working shear force, and the top plate is connected to a node plate embedded in a structural member. The top plate and bottom plate are connected by the vertical web plates and the inclined web plate units. The vertical web plates bear the vertical additional force and part of the shear force generated when the shear-type seismic energy dissipator is working. There is space between the vertical web plates for arranging the inclined web plate units. Each inclined web plate unit includes two non-connected inclined web plates that are mirror-symmetrical. The inclined web plates bear the remaining shear force generated when the shear-type seismic energy dissipator is working. The displacement measuring device measures the shear deformation of the inclined web plates under shear force, and then calculates the working shear force of the shear-type seismic energy dissipator by the relationship between the shear deformation and the shear force of the device.

Description

Technical Field

[0001] This invention belongs to the field of engineering structural health monitoring and testing technology, specifically relating to a device and method for measuring the working shear force of shear-type seismic energy dissipators. Background Technology

[0002] In areas with seismic fortification intensity of 8 degrees or above, and in key earthquake monitoring and defense zones, seismic isolation and damping technologies are typically used when reinforcing newly constructed schools, kindergartens, hospitals, elderly care institutions, children's welfare institutions, emergency command centers, emergency shelters, radio and television stations, and other buildings of the above types, as well as existing buildings. Seismic energy dissipators are a core component of seismic isolation and damping technology. Their function is to dissipate the energy absorbed by the building structure during an earthquake, thereby reducing the structure's vibration response and protecting the building structure. Therefore, the performance of seismic energy dissipators during their operational phase is crucial for ensuring the normal functioning of such buildings during earthquakes and is a key factor in evaluating the seismic performance of existing buildings. Currently, existing literature on monitoring the operational status of seismic energy dissipators mainly focuses on viscous dampers and magnetorheological dampers, typically achieved by installing pressure and liquid temperature sensors.

[0003] Shear-type energy dissipators, which primarily rely on shear deformation, are a widely used type of damper in building structures. They mainly consist of a core plate and restraint steel plates, dissipating energy through plastic hysteretic deformation caused by the shear yielding of the highly ductile core plate. Currently, performance testing of shear-type energy dissipators is primarily conducted in laboratory environments. Testing machines are used to subject the energy dissipators to low-cycle cyclic loading, measuring shear force and shear displacement to generate shear force-displacement hysteresis curves, thereby inferring their performance. Existing technologies rarely address the monitoring of the operational performance of shear-type energy dissipators during service.

[0004] Currently, research on the performance monitoring of seismic energy dissipators during operation mainly focuses on frictional, viscous, and eddy current types. The operating characteristics of these dissipators primarily involve deformation and damping force generated by tension or compression at the fixed end. Changes in the working force can be directly measured using tension / compression sensors or indirectly measured through indicators such as oil pressure and eddy current magnetic field within the dissipator cavity. In contrast, shear-type seismic energy dissipators operate by generating deformation and damping force through misalignment at the fixed end, with the damping force primarily manifesting as shear force. Due to varying installation methods in engineering sites, the stress state of shear-type seismic energy dissipators sometimes exhibits shear-bending behavior, and under rare earthquake conditions, it may even exhibit a complex mechanical state of shear-bending-torsion. Through the study and analysis of existing force measurement methods using finite element model, the existing devices used to measure the working shear force of shear-type seismic energy dissipators have the following problems: (1) The mechanical model assumptions and simplifications are inaccurate, with large errors or even mistakes; (2) The force measuring device cannot withstand earthquakes with large amplitudes and high frequencies. If a complex stress state occurs accidentally during the working stage, the existing force measuring device cannot work properly; (3) It changes or reduces the original working performance of the shear-type seismic energy dissipator. Summary of the Invention

[0005] To address the problems in the prior art, this invention provides an apparatus and method for measuring the working shear force of shear-type seismic energy dissipators.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention discloses a device for measuring the working shear force of a shear-type seismic energy dissipator, comprising a top plate, a bottom plate, multiple vertical webs, multiple inclined web units, and a displacement measuring device. The bottom plate is connected to the end plate of the shear-type seismic energy dissipator to be measured for working shear force. The top plate is connected to a node plate embedded in a structural member. The top plate and the bottom plate are connected by the vertical webs and the inclined web units. The vertical webs are used to bear the vertical additional force and part of the shear force generated when the shear-type seismic energy dissipator is working. There is space between the vertical webs for arranging the inclined web units. Each inclined web unit comprises two non-connected inclined webs that are mirror-symmetrical. The inclined webs are used to bear the remaining shear force generated when the shear-type seismic energy dissipator is working. The angle between the inclined webs and the top plate is set so that the thickness of the inclined webs is linearly related to the shear deformation displacement of the inclined webs. The displacement measuring device is used to measure the shear deformation displacement of the inclined webs in the direction of shear force.

[0008] Furthermore, the device is designed using the following steps:

[0009] 1) First, determine the dimensional information of the top plate and the bottom plate respectively. At the same time, based on the width of the node plate, determine the number of devices to be installed when measuring the shear force of the shear-type seismic energy dissipator to be measured.

[0010] Next, determine the width, height, and thickness of the vertical web to ensure that the working stress and strain of the vertical web under the vertical additional force are within the elastic range of its own material.

[0011] Then, determine the included angle between the inclined web and the top plate and the thickness of the inclined web. Then, based on the net distance between two adjacent vertical webs, determine the number of inclined webs between the two vertical webs. Then, determine the number of inclined webs in the device. Among them, the net distance between two adjacent inclined webs is not less than twice the thickness of the inclined web, and the net distance between a vertical web and its adjacent inclined web is not less than the thickness of the vertical web.

[0012] 2) Based on the shear strength and tensile strength of the material of the vertical web, obtain the maximum shear force that the vertical web can withstand, and the shear deformation displacement under the obtained maximum shear force.

[0013] Next, obtain the shear force, shear stress, and principal stress of the inclined web element when it undergoes the same shear deformation displacement. Compare the shear stress with the shear strength of the inclined web material, and compare the principal stress with the tensile strength of the inclined web material. If the shear stress is greater than the shear strength or the principal stress is greater than the tensile strength, then use the material strength of the inclined web as the control index to obtain the maximum shear force and the shear deformation displacement of the inclined web element, and calculate the shear force of the vertical web when it undergoes the same shear deformation displacement; otherwise, proceed directly to step 4).

[0014] 3) Based on the number of devices installed, obtain the shear force transmitted by the seismic energy dissipator for each device. Then, based on the shear force on the inclined web unit and the vertical web obtained in step 2), calculate the total shear force value of the device. If the total shear force value is greater than or equal to the shear force transmitted by the seismic energy dissipator for the device, the device design is complete; otherwise, return to step 1) to adjust the dimensions of the inclined web, vertical web, top plate and bottom plate, or change the material of the device.

[0015] Secondly, this invention discloses a method for measuring the working shear force of a seismic energy dissipator based on the aforementioned device, comprising: firstly, determining the number of devices to be installed when measuring the working shear force of a shear-type seismic energy dissipator to be measured based on the width of the node plate; then installing all the devices, wherein the devices are parallel to each other, and the deformation direction of each device is consistent with the deformation direction of the shear-type seismic energy dissipator; when the shear-type seismic energy dissipator deforms under seismic action, obtaining the displacement change of each displacement measuring device at the current moment, and calculating the average displacement change ΔL of all displacement measuring devices; finally, based on the formula... The shear force Vi acting on the device is obtained. Vi is multiplied by the number of devices arranged to obtain the shear force of the shear-type seismic energy dissipator, where f is the shear deformation displacement of the inclined web element finally obtained in step 2).

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0017] (1) The vertical web plate in the device is used to bear the vertical additional force and part of the shear force of the seismic energy dissipator, and the inclined web plate is used to bear the remaining shear force of the seismic energy dissipator. The reliability and stability of the device under repeated seismic shear loads are ensured by mirroring the inclined web plate.

[0018] (2) When the inclined webs are tilted at a certain angle and a certain net distance is maintained between each web, the shear displacement and shear force of the device exhibit linear variation characteristics. The shear force variation borne by the device is calculated by measuring the shear displacement variation. The mechanical model of this invention is accurately assumed and simplified, and can obtain the working shear force (or damping force) variation of the seismic energy dissipator under seismic action in real time. Combined with a structural health monitoring system, the working status or performance of the seismic energy dissipator can be evaluated online during and after an earthquake, which helps to ensure building safety during a major earthquake. Furthermore, this invention does not change the original working performance of the shear-type seismic energy dissipator.

[0019] (3) This invention, combined with real-time displacement monitoring data of the seismic energy dissipator, can obtain the shear force-displacement hysteresis curve under the working state of the seismic energy dissipator. This provides real and accurate performance information of the seismic energy dissipator for seismic isolation and reduction design and improvement. Engineering design units can verify the effectiveness of seismic design based on the actual working performance of the seismic energy dissipator, or take timely and effective supplementary seismic measures to improve the efficiency and reliability of seismic isolation and reduction.

[0020] (4) This invention can also be used to verify and improve the existing theoretical calculation model of seismic energy dissipators, help the technical personnel of seismic energy dissipators manufacturers to further understand the real behavior of seismic energy dissipators under seismic action, thereby improving the design level of seismic energy dissipators products.

[0021] (5) The dimensions of the device of this invention can be adjusted according to different models and sizes of seismic energy dissipators, making it highly adaptable. The installation process is simple and the connection is reliable, without altering the original production and installation processes of the seismic energy dissipator or the structural connection details of the engineering structure. With slight modifications, the device of this invention can also be used for monitoring the working shear force of seismic isolation bearings. This invention has a reasonable cost and high economic benefits. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the main components of a device suitable for measuring the working shear force of shear-type seismic energy dissipators;

[0023] Figure 2 This is an axial view schematic diagram of a device suitable for measuring the working shear force of shear-type seismic energy dissipators;

[0024] Figure 3It is a graph showing the relationship between web thickness and shear deformation displacement;

[0025] Figure 4 This is a calculation model diagram of the vertical web.

[0026] Figure 5 This is a calculation model diagram of a 30° inclined web element;

[0027] Figure 6 This is a schematic diagram of the geometric dimensions of a device suitable for measuring the working shear force of shear-type seismic energy dissipators;

[0028] Figure 7 This is an installation diagram of a device suitable for measuring the working shear force of shear-type seismic energy dissipators. Detailed Implementation

[0029] The present invention will be further described and illustrated below with reference to specific embodiments. The embodiments described are merely examples of the content of this disclosure and do not limit the scope of the invention. The technical features of each embodiment in the present invention can be combined accordingly, provided that there is no mutual conflict.

[0030] When designing vibration reduction for engineering structures, the end plate of a shear-type seismic energy dissipator is generally connected to the node plate 9 embedded in the structural member. To measure the working shear force of the shear-type seismic energy dissipator, a shear force measuring device is installed between the end plate and the node plate. The purpose of this invention is to measure the shear force borne by the shear-type seismic energy dissipator during operation. A device and method suitable for measuring the working shear force of the shear-type seismic energy dissipator have been developed. Combined with the working displacement information of the shear-type seismic energy dissipator, the working status and performance of the shear-type seismic energy dissipator can be monitored and evaluated online.

[0031] To achieve the above objectives, the proposed solutions include the design of the device, the installation of the device, and the measurement of the device's deformation and the calculation of its shear force.

[0032] First, such as Figure 1 , Figure 2 and Figure 7As shown, the device for measuring the working shear force of a shear-type seismic energy dissipator according to the present invention includes a top plate 1, a bottom plate 4, two vertical web plates 3, multiple inclined web plate units, and a displacement measuring device 8. The bottom plate 4 is connected to the end plate 10 of the shear-type seismic energy dissipator to be measured for working shear force. The top plate 1 is connected to the node plate 9 embedded in the structural member. The top plate 1 and the bottom plate 4 are connected by the vertical web plates 3 and the inclined web plate units. The vertical web plates 3 are used to bear the vertical additional force and part of the shear force generated when the shear-type seismic energy dissipator is working, and there is space between the two vertical web plates 3 for arranging the inclined web plate units. The inclined web unit includes two non-connected inclined webs 2 that are mirror-symmetrical. The inclined webs 2 bear the remaining shear force generated during the operation of the shear-type seismic energy dissipator. A certain net distance is maintained between the vertical web 3 and its adjacent inclined web 2, and also between adjacent inclined webs 2. A certain angle is set between the inclined webs 2 and the top plate 1, so that the thickness of the inclined web 2 is approximately linearly related to its shear deformation displacement. A strain gauge, i.e., a displacement measuring device 8, for measuring shear deformation is installed at the middle position of the top plate 1 to measure the shear displacement of the inclined web 2 in the direction of shear force. Structural components are the basic components in engineering structures such as buildings and bridges that bear loads and transmit forces. In this invention, structural components can be beams, columns, or shear walls, etc.

[0033] In one specific embodiment of the present invention, the present invention also provides a design method for a device suitable for measuring the working shear force of a shear-type seismic energy dissipator.

[0034] Working principle: Figure 1 and Figure 2 The shear force measuring device (i.e., a device suitable for measuring the working shear force of shear-type seismic energy dissipators) shown includes a top plate 1, a bottom plate 4, multiple vertical webs 3 arranged between the top plate 1 and the bottom plate 4, and inclined webs 2 at a certain angle. When subjected to a longitudinal shear force V, the top plate 1 and the bottom plate 4 generate shear displacement along the direction of shear force V. The shear force V is mainly borne by the inclined webs 2 at a certain angle. These inclined webs 2 are the main components for realizing shear force measurement. Their stress characteristics are mainly tensile shear and compressive shear, reducing the influence of the non-perfectly rigid connection at the ends of the webs. The shear displacement at the upper and lower ends is close to the linear relationship with the shear force, providing a framework for the design of the shear force measuring device and the calculation of shear force by measuring the shear displacement. The vertical additional force that may be generated when the shear-type seismic energy dissipator is working is borne by the vertical webs 3. The main function of the vertical webs 3 is to transmit the vertical additional force of the seismic energy dissipator or resist the action of other accidental loads, and at the same time, it can transmit part of the shear force (or damping force). By using a specially designed inclined web 2 with appropriate inclination angle, web size, quantity, and distribution, the shear displacement and shear force of the shear force measuring instrument are made to exhibit a linear relationship. Then, the strain gauge, i.e., the displacement measuring instrument 8, installed on the shear force measuring instrument, reads the measured values ​​and calculates points 1 and 2. Figure 1The displacement change Δl at the location shown is measured in the shear direction, and then the shear force is calculated based on the linear relationship. Simultaneously, by configuring the vertical web 3 and the inclined web 2, and adjusting their respective dimensions and number, the shear force gauge can adapt to different models of shear-type seismic energy dissipators and the requirements of different seismic actions.

[0035] The shear force measuring device is made of metals with good elastic deformation capacity, such as low-carbon steel Q235 or alloy steel chromium steel, or it can be made from thick steel plates or bars through machining. The thickness and width of the top plate 1 and bottom plate 4 are adjusted according to the working shear force of the shear-type seismic energy dissipator and the node plate 9 and end plate 10 to meet the connection strength and stiffness. The inclined web plate 2 and vertical web plate 3 are configured according to the shear force design value of the shear-type seismic energy dissipator.

[0036] The top plate 1 is connected to structural components such as beams, shear walls, or columns; the bottom plate 4 is connected to the end plates of the shear-type seismic energy dissipator. These connections are typically made by welding or bolting. When bolting is used, the spacing between the vertical web plate 3 and the inclined web plate 2 needs to be adjusted to meet the bolting requirements, and the connection strength must be considered. The thickness of the top plate 1 and the bottom plate 4 is determined based on the design value of the shear force (or damping force) of the shear-type seismic energy dissipator, the connection method, etc., and their strength and stiffness should ensure that the shear force gauge can effectively transmit the shear force and guarantee the working performance of the shear-type seismic energy dissipator.

[0037] The inclined web 2 is mainly used to bear the shear force between the engineering structure and the shear-type seismic energy dissipator during an earthquake. The vertical web 3 mainly bears the additional vertical force of the shear-type seismic energy dissipator, and can also bear some shear force. Considering the complexity of the seismic response of the engineering structure, the shear-type seismic energy dissipator may generate both shear force and vertical force simultaneously during an earthquake. In this case, the shear force gauge will be subjected to repeated action of shear force and vertical force. Therefore, the inclined web 2 and the vertical web 3 should be subjected to compressive stability analysis to ensure that their bearing capacity meets both strength and stability requirements.

[0038] The width, thickness, and number of the inclined web 2 and vertical web 3 of the shear force measuring device are determined by the geometric dimensions of the shear-type seismic energy dissipator, the design value of the shear force (or damping force), and the dimensions of the node plate 9 and the end plate 10. According to theoretical analysis, when the web angle is 90°, the web ends are subject to the incomplete rigid constraints of the top plate 1 and bottom plate 4 of the same material, and the influence of the web thickness, resulting in a complex distribution of stress and strain along the length of the web section. The stress and strain of the web section near the top plate 1 and bottom plate 4 no longer conform to the thin plate plane section assumption, and the distribution of stress and strain along the web length varies significantly. The shear force V obtained by directly measuring the web strain has a large error. Simultaneously, the change in web thickness and its shear deformation under the same shear force V exhibits nonlinearity, such as... Figure 3As shown. However, when the web angle gradually decreases to about 30°, the stress characteristics of the web gradually change from bending shear to tension shear, but the distribution of stress and strain along the length of the web remains complex, and establishing a theoretical relationship between stress, strain, and shear force V is still difficult; however, according to Figure 3 Analysis shows that under a shear force V = 1 kN and an inclination angle of ±30°, the change in the cross-sectional thickness of the inclined web 2 is nearly linear with its shear deformation. This provides a basis for calculating the shear force V by measuring the shear displacement of the inclined web 2 at ±30°. Furthermore, when the shear force measuring instrument is designed according to certain structural requirements, the workload of calculation and analysis can be reduced.

[0039] The design of a shear force measuring device shall be carried out according to the following main steps:

[0040] The first step is to determine the length, width, and thickness of the top plate 1 and bottom plate 4 of the shear force measuring device based on the magnitude of the shear force (or damping force) and additional vertical force of the shear-type seismic energy dissipator, the size of the node plate of the embedded part of the structural component, and the connection method. It is also to determine the number of devices to be installed when measuring the shear force of the shear-type seismic energy dissipator to be measured. If necessary, the calculations should be performed according to the connection strength and stiffness requirements.

[0041] Specifically, the thickness of the top plate 1 is greater than the thickness of the node plate 9, and the length is less than the length of the node plate 9. The ratio of the width of the top plate 1 to the height of the shear force measuring device is generally 2 / 3 to 1, wherein the height of the shear force measuring device is generally less than 100mm. The length of the bottom plate 4 is consistent with the length of the top plate 1, the width of the bottom plate 4 is consistent with the width of the top plate 1, and the thickness of the bottom plate 4 is consistent with the thickness of the top plate 1.

[0042] The second step involves determining the position, height, width, and thickness of the vertical web plate 3 based on the embedded parts of the structural components and the requirements of the additional vertical force of the shear-type seismic energy dissipator. This ensures that the vertical web plate 3 can effectively transmit the additional vertical force, that the stress and strain of the vertical web plate 3 during operation are within the elastic range, and that it does not affect the connection structure between the node plate of the embedded parts and the top plate 1 of the shear force measuring device, or between the end plate of the shear-type seismic energy dissipator and the bottom plate 4 of the shear force measuring device.

[0043] Specifically, the node plate 9 is connected to the vertical plate embedded in the structural member, and the vertical web plate 3 is arranged in the same vertical direction as the vertical plate; that is, as shown in the figure. Figure 7As shown, the flanges of the vertical web plate 3 and the embedded H-beam are arranged in the same vertical direction. The sum of the height of the vertical web plate 3, the thickness of the top plate 1, and the thickness of the bottom plate 4 is equal to the height of the shear force measuring device. The width of the vertical web plate 3 is equal to the width of the top plate 1, and generally, the width is not less than 2 / 3 of the height of the shear force measuring device. The thickness of the vertical web plate 3 is determined by the vertical additional force of the seismic energy dissipator and the vertical compressive stability, and is less than or equal to 1 / 2 of the thickness of the top plate 1 or the bottom plate 4. If this condition is not met, the thickness of the top plate 1 and the bottom plate 4 should be increased.

[0044] The third step is to first determine the included angle between the inclined web 2 and the top plate 1, as well as the thickness of the inclined web 2. In a specific embodiment of the present invention, the included angle can be designed to be 30°. Generally, the thickness of the inclined web 2 does not exceed half the thickness of the vertical web 3. Generally, the net distance between two adjacent inclined webs 2 should not be less than twice the thickness of the inclined web 2, and the net distance between the vertical web 3 and its adjacent inclined web 2 should not be less than once the thickness of the vertical web 3.

[0045] Next, determine the number of inclined webs 2. First, subtract twice the net distance between the vertical web 3 and its adjacent inclined web 2 from the net distance between two adjacent vertical webs 3 to obtain the distance between two adjacent vertical webs 3 for arranging inclined webs 2.

[0046] Then, based on the included angle between the inclined web 2 and the top plate 1 and the thickness of the inclined web 2, the length of the horizontal projection of the inclined web 2 is calculated. Then, the horizontal projection length of the inclined web 2 plus the net distance between two adjacent inclined webs 2 is used as the module of the inclined web 2. Then, the distance of the inclined web 2 arrangement plus the net distance between two adjacent inclined webs 2 is used as the corrected arrangement distance.

[0047] Then, the corrected arrangement distance is divided by the module of the inclined web 2 to calculate the number a of the inclined web 2 between two adjacent vertical webs 3. If the calculated a is not an integer, the number of inclined webs between two adjacent vertical webs 3 is determined by rounding down.

[0048] Finally, the number of inclined webs between every two adjacent vertical webs 3 is calculated and then summed to obtain the number of inclined webs 2 in the device.

[0049] The fourth step involves calculating the maximum shear force V1 and shear displacement f1 borne by the vertical web 3 based on the material strength of the shear force measuring instrument and the dimensional information of the vertical web 3. A schematic model is shown below. Figure 4 .

[0050] Specifically, based on the shear strength and tensile strength of the material of the vertical web 3, the maximum shear force that the vertical web 3 can withstand and the corresponding shear deformation displacement of the vertical web 3 are obtained using a finite element model.

[0051] In the fifth step, during the initial calculation, the width of the 30° inclined web 2 is the same as the width of the vertical web 3. Then, according to the web shear deformation coordination principle of the shear force measuring instrument, such as... Figure 1 As shown, the shear deformation f2 = f1 of the inclined web 2 is determined, and the shear force V2 that a single inclined web element should bear is calculated using the finite element model, as follows. Figure 5 As shown. Simultaneously, the shear stress and principal stress corresponding to the same shear deformation displacement f2 of the inclined web element are calculated. The calculated shear stress of the inclined web element must be lower than the shear strength of its material, and the calculated principal stress of the inclined web element must be lower than the tensile strength of its material. When the calculated shear stress of the inclined web element is greater than the shear strength or the principal stress is greater than the tensile strength, the shear force V2 (i.e., the maximum shear force on the inclined web element is calculated as the updated V2) and shear deformation displacement f2 are recalculated using the material strength of the inclined web 2 as the control index. The shear force V1 and shear deformation displacement f1 of the vertical web 3 are then updated according to the deformation compatibility principle, i.e., f1 = f2.

[0052] Step 6: Assuming the shear force design value of the shear-type seismic energy dissipator is V0, and the number of shear force measuring instruments installed is j, then the total shear force of the shear force measuring instruments should satisfy V0. v ·j=(mV1+nV2)·j≥V0, where m is the number of vertical web elements (3), and n is the number of oblique web elements, which can be calculated as an integer multiple of 0.5. When n is an odd multiple of 0.5, the number of oblique web elements is odd. If V0 is not satisfied... v If j = (mV1 + nV2)·j ≥ V0, then return to step one, adjust the geometric dimensions or material strength of the device, and redesign steps one through six. (II) Installation of the shear force measuring device

[0053] Shear force gauges are installed between shear-type seismic energy dissipators and structural components such as beams, walls, and columns in the engineering structure. Installation methods typically include welded connections and bolted connections. In engineering projects, shear-type seismic energy dissipators are generally welded to or bolted to node plates 9 embedded in concrete via their upper end plate. When a shear force gauge is installed between node plate 9 and the shear-type seismic energy dissipator, node plate 9 is connected to the top plate 1 of the shear force gauge using the same connection method, and the upper end plate of the shear-type seismic energy dissipator is connected to the bottom plate 2 of the shear force gauge in the same way. The welded or bolted connection design should ensure that the shear force (or damping force) is uniformly transmitted along the length of the shear force gauge and that the vertical force is effectively transmitted along the vertical web plate 3.

[0054] (III) Deformation Measurement and Shear Force Calculation Using Shear Force Gauge

[0055] The shear force measuring device located between the shear-type seismic energy dissipator and structural components such as beams, walls, and columns should effectively transmit shear force (or damping force), and the shear deformation of the shear force measuring device should not change the mechanical model of the original structure's seismic isolation design. Therefore, the shear deformation of the shear force measuring device should be small. Furthermore, the shear force under seismic action is a dynamic load, and the accuracy, range, and data acquisition frequency of the shear displacement measuring instrument 8 of the shear force measuring device must meet the relevant national standards. If the shear-type seismic energy dissipator is also equipped with a working displacement monitoring device, it is important to ensure that the sampling frequencies of shear force and working displacement are consistent to meet the requirements for plotting the working hysteresis curve of the shear-type seismic energy dissipator, so as to evaluate the working performance of the seismic energy dissipator online.

[0056] The number of devices to be installed for shear force measurement of the shear-type seismic energy dissipator to be measured is determined based on the width of the node plate 9. Then, all the devices are installed, with the devices parallel to each other and the deformation direction of each device consistent with the deformation direction of the shear-type seismic energy dissipator. When the shear-type seismic energy dissipator deforms under seismic action, the reading of each displacement measuring device 8 at the current moment is obtained, and the average value of the readings of all displacement measuring devices 8 is calculated to obtain the average displacement change ΔL of the device.

[0057] Finally, use the formula The shear force Vi acting on the device is obtained. Vi is multiplied by the number of shear force measuring instruments arranged to obtain the shear force of the shear-type seismic energy dissipator, where f is the shear deformation displacement of the inclined web element finally obtained in the fifth step.

[0058] The following figures illustrate specific embodiments of the present invention in further detail. The embodiments are mainly implemented according to the following steps.

[0059] Shear force measuring device design

[0060] (1) Design load of shear-type seismic energy dissipator

[0061] Figure 7 The maximum design shear force of the shear-type seismic energy dissipator shown is 330kN. Considering an additional vertical force of 20%–25% of the shear force, the value is 66kN–85.5kN.

[0062] (2) Shear-type seismic energy dissipator and concrete shear wall connection

[0063] Figure 7 The node plate 9 of the pre-embedded part connecting the shear-type seismic energy dissipator and the concrete shear wall shown has a thickness of 12mm, a length of 470mm, and a width of 200mm. The H-shaped steel flange spacing of the pre-embedded part is 370mm, the flange thickness is 18mm, and the web thickness is 12mm.

[0064] (3) Connection method of shear-type seismic energy dissipator and connector

[0065] In traditional design, Figure 7 The upper plate 10 of the shear-type seismic energy dissipator shown is connected to the node plate 9 in the concrete shear wall by three-sided welding.

[0066] S1: The shear force measuring device is made of Q420 steel. The height of the shear force measuring device is 60mm, the thickness of the top plate 1 and bottom plate 4 is 20mm, the length is 430mm, and the width is tentatively 40mm. This implementation scheme uses the same welding connection method as the original design. The thickness of the top plate 1 and bottom plate 4 of the shear force measuring device is greater than the thickness of the node plate 9. Simultaneously, the material strength of the shear force measuring device is greater than that of the node plate 9, therefore its strength and stiffness can effectively transfer shear force. Based on the width of the node plate 9, this scheme initially determines to use two shear force measuring devices for shear force measurement.

[0067] S2: According to the design overview, the vertical additional force of the shear-type seismic energy dissipator is taken as 84kN. In this implementation plan, each shear force measuring device has two vertical web plates 3 used to transmit the vertical additional force. The positions correspond to the flanges of the H-beam embedded parts (aligned). The thickness of the vertical web plate 3 is 10mm, the vertical height is 20mm, and the net distance between the two vertical web plates 3 is 370-18-18+2×[1 / 2×(18-10)]=342mm. The width of the vertical web plate 3 is consistent with the width of the top plate 1, which is taken as 40mm. The vertical additional force is borne by the vertical web plate 3. The vertical additional force on a single vertical web plate 3 in each shear force measuring device is 21kN=84kN / (2+2). Considering the compression state, the compressive stress is 52.5MPa. The vertical web plate 3 is within the elastic range, and the height-to-thickness ratio meets the requirements for compressive stability.

[0068] S3: The thickness of the inclined web 2 is half the thickness of the vertical web 3, i.e., 5mm. The vertical height of the inclined web 2 is the same as the height of the vertical web 3, both being 20mm. Therefore, the horizontal projection distance (the dimension in the shear force direction) from the left end point to the right end point of an inclined web 2 is (20 / tan30°) + (5 / sin30°) = 44.64mm, which is taken as 45mm.

[0069] The number of inclined web plates 2 is determined next, based on the third step of the shear force measuring device design.

[0070] In this case, the net distance between the two vertical webs minus twice the thickness of the vertical webs is 342 - 10 - 10 = 322 mm, which serves as the space for arranging the inclined webs. The horizontal projection distance of one inclined web plus twice the thickness of the inclined web is 45 + 5 + 5 = 55 mm, which serves as the module of the inclined web. However, the net distance between the inclined webs and the vertical webs is shared by 10 mm, so the space for arranging the inclined webs is corrected to 322 + 5 + 5 = 332 mm. 332 / 55 = 6.03, rounded down to 6, therefore, three inclined web elements can be arranged in this case. A schematic diagram of the shear force measuring device's geometric dimensions is shown below. Figure 6 Installation instructions are as follows: Figure 7 .

[0071] S4: The shear force measuring instrument is made of Q420 steel, with a shear strength of 185 MPa and a tensile strength of 320 MPa. When the shear force is 20 kN... Figure 4 The model has a maximum shear stress of 121.9 MPa and a maximum principal stress of 315.4 MPa, which meet the design values ​​for shear and tensile strength.

[0072] Therefore, based on the material strength and the dimensions of the vertical web 3, Figure 4 The model can withstand the maximum shear force V within the limits of material strength. 1＝ 20kN corresponds to a shear deformation displacement f1 = 0.0568mm under the maximum shear force.

[0073] S5: Based on the shear deformation coordination principle of the vertical web 3 and the 30° inclined web 2 working together in the shear force measuring instrument. Figure 5 When the shear deformation of the inclined web element reaches 0.0568 mm, the corresponding shear force obtained through the finite element model is approximately 81.1 kN. At this time, the maximum shear stress of the inclined web element is 185.4 MPa, and the maximum principal stress is 274.6 MPa. Since the maximum shear stress of the inclined web element exceeds the design shear strength of 185 MPa, the material strength of the inclined web is used as the control index for calculation. Taking the shear force V2 of the inclined web element as 80 kN, and assuming the stress meets the material design strength, the shear deformation displacement of the inclined web element is 0.0530 mm. Therefore, the shear deformation displacement f2 is taken as 0.0530 mm. The shear deformation displacement f1 of the vertical web 3 is reduced to 0.0530 mm, at which point the shear force V1 of the vertical web 3 is 18.66 kN. The maximum shear displacement value of the force gauge is f = 0.0530 mm.

[0074] S6: According to this implementation plan, two shear force gauges are arranged along the width direction at the lower part of node plate 9. Each shear force gauge bears the shear force transmitted by the seismic energy dissipator, which is V0 = 330 / 2 = 165kN. Based on the conclusion of S5, the total shear force value that the shear force gauges can bear is Vv = mV1 + nV2 = 2 × 18.66 + 3 × 80 = 277.32kN ≥ V0. The sum of the total shear forces of the two shear force gauges is greater than the design shear force of the shear-type seismic energy dissipator, and the design is complete. If the sum of the maximum shear forces of the shear force gauges is less than the shear force borne by the shear-type seismic energy dissipator, then return to S1, adjust the geometric dimensions or material strength of the device, and redesign S1 to S6.

[0075] Considering the displacement measurement method, the displacement measuring device 8 in this implementation scheme is a strain gauge with a gauge length of 34.64 mm. Based on the strain gauge range of ±2000 με, the measurable shear deformation range is ±0.0692 mm, with a measurement accuracy of 0.5‰. The accuracy and range of the selected strain gauge meet the measurement requirements.

[0076] (II) Installation of Shear Force Measuring Instrument

[0077] The end plate 10 of the shear-type seismic energy dissipator is connected to the node plate 9 by three-sided welding. This implementation plan uses the welded connection as an example to illustrate the installation steps. The installation of the shear force measuring device is carried out in the following three steps.

[0078] S1: Weld the base plate 4 of the shear force measuring device to the end plate 10 of the shear type seismic energy dissipator. Each shear force measuring device is connected to the upper end plate 10 of the shear type seismic energy dissipator by two welds 5. The welds must meet the connection strength requirements.

[0079] Meanwhile, each shear force measuring device is connected to the node plate 9 by two welds, the weld positions of which are as follows: Figure 7 Weld 6 in the middle. On the node plate 9, a groove is set according to the position of the shear force measuring device for the connection of the inner weld of the force measuring device. The size of the groove must meet the weld strength requirements of the force measuring device.

[0080] S2: Holes are drilled at the locations where the inclined web 2 in the middle of the shear force measuring device connects the bottom plate 4 and the top plate 1. A strain gauge bracket 7 is installed at the hole in the bottom plate 4. One end of the strain gauge (displacement measuring device 8) is then bolted to the top plate, and the other end is fixed to the strain gauge bracket 7. In this embodiment, one strain gauge with the same gauge length is installed on each of the two shear force measuring devices.

[0081] (III) Deformation Measurement and Shear Force Calculation Using Shear Force Gauge

[0082] When the shear-type seismic energy dissipator undergoes shear deformation under seismic loading, the readings ε1 and ε2 of each strain gauge at the current moment are obtained. The average reading ε of all strain gauges is calculated, and then the average reading is multiplied by the strain gauge gauge length to obtain the shear displacement change of the device. In a specific embodiment of the present invention, the strain gauge gauge length l = 34.64 mm, therefore the average displacement change ΔL at this time is 34.64ε. Finally, based on the formula... Obtain the shear force Vi acting on the shear force measuring instrument.

[0083] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. Those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A device for measuring the working shear force of a shear-type seismic energy dissipator, characterized in that, It includes a top plate (1), a bottom plate (4), multiple vertical web plates (3), multiple inclined web plate units, and a displacement measuring device (8); the bottom plate (4) is connected to the end plate (10) of the shear-type seismic energy dissipator to be measured for working shear force, the top plate (1) is connected to the node plate (9) embedded in the structural member, and the top plate (1) and the bottom plate (4) are connected by vertical web plates (3) and inclined web plate units. The vertical web plates (3) are used to bear the vertical additional force and part of the shear force generated when the shear-type seismic energy dissipator is working, and there is space between the vertical web plates (3) for arranging the inclined web plate units. The element includes two non-connected inclined web plates (2) that are mirror-symmetrical. The inclined web plates (2) are used to bear the remaining shear force generated when the shear-type seismic energy dissipator is working. The angle between the inclined web plates (2) and the top plate (1) is set so that the thickness of the inclined web plates (2) is linearly related to the shear deformation displacement of the inclined web plates (2). The displacement measuring device (8) is used to measure the shear deformation displacement of the inclined web plates (2) in the direction of shear force. The net distance between two adjacent inclined web plates (2) is not less than twice the thickness of the inclined web plates (2), and the net distance between the vertical web plate (3) and its adjacent inclined web plates (2) is not less than the thickness of the vertical web plate (3).

2. The apparatus according to claim 1, characterized in that, The top plate (1), bottom plate (4), vertical web plate (3) and inclined web plate (2) are made of low carbon steel or alloy steel.

3. The apparatus according to claim 1, characterized in that, The thickness of the top plate (1) is not less than twice the thickness of the vertical web plate (3) and greater than the thickness of the node plate (9), and the length is less than the length of the node plate (9). The width of the top plate (1) is in the ratio of 2 / 3 to 1 to the height of the device, wherein the height of the device is less than 100mm. The size information of the bottom plate (4) is consistent with the size information of the top plate (1), and the size information includes length, width and thickness.

4. The apparatus according to claim 1, characterized in that, The node plate (9) is connected to the vertical plate embedded in the structural member, and the vertical web plate (3) and the vertical plate are arranged in the same vertical direction; the sum of the height of the vertical web plate (3), the thickness of the top plate (1) and the thickness of the bottom plate (4) is equal to the height of the device, the width of the vertical web plate (3) is less than or equal to the width of the top plate (1), and the thickness of the vertical web plate (3) is less than or equal to 1 / 2 of the thickness of the top plate (1) or the bottom plate (4); the thickness of the inclined web plate (2) does not exceed 1 / 2 of the thickness of the vertical web plate (3), and the width of the inclined web plate (2) is equal to the width of the vertical web plate (3).

5. The apparatus according to claim 4, characterized in that, The device was designed using the following steps: 1) First, determine the size information of the top plate (1) and the bottom plate (4), and at the same time, determine the number of devices to be installed when measuring the shear force of the shear-type seismic energy dissipator to be measured based on the width of the node plate (9); Then determine the width, height and thickness of the vertical web (3) to ensure that the working stress and strain of the vertical web (3) under the vertical additional force are within the elastic range of its own material; Then determine the included angle between the inclined web (2) and the top plate (1) and the thickness of the inclined web (2), and then determine the number of inclined webs between the two vertical webs (3) based on the net distance between the two adjacent vertical webs (3), and then determine the number of inclined webs (2) in the device. 2) Based on the shear strength and tensile strength of the material of the vertical web (3), obtain the maximum shear force that the vertical web (3) can withstand, and the shear deformation displacement under the action of the obtained maximum shear force; Next, obtain the shear force, shear stress, and principal stress of the inclined web unit when it undergoes the same shear deformation displacement. Compare the shear stress with the shear strength of the inclined web (2) material and the principal stress with the tensile strength of the inclined web (2) material. If the shear stress is greater than the shear strength or the principal stress is greater than the tensile strength, then use the material strength of the inclined web (2) as the control index to obtain the maximum shear force and the shear deformation displacement of the inclined web unit, and calculate the shear force of the vertical web (3) when it undergoes the same shear deformation displacement; otherwise, proceed directly to step 4). 3) Based on the number of devices installed, obtain the shear force transmitted by the seismic energy dissipator for each device, and then calculate the total shear force value of the device based on the shear force of the inclined web unit and the vertical web (3) obtained in step 2). If the total shear force value is greater than or equal to the shear force transmitted by the seismic energy dissipator for the device, the device design is complete; otherwise, return to step 1) to adjust the size of the inclined web (2), the vertical web (3), the top plate (1) and the bottom plate (4), or change the material of the device.

6. The apparatus according to claim 5, characterized in that, In step 1), the number of inclined webs in the device is determined based on the net spacing between the vertical webs (3), including the following steps: First, subtract twice the net distance between the vertical web (3) and its adjacent inclined web (2) from the net distance between two adjacent vertical webs (3) to obtain the distance between two adjacent vertical webs (3) for arranging inclined webs (2); Then, based on the angle between the inclined web (2) and the top plate (1) and the thickness of the inclined web (2), the length of the horizontal projection of the inclined web (2) is calculated. Then, the horizontal projection length of the inclined web (2) plus the net distance between two adjacent inclined webs (2) is used as the module of the inclined web (2). Then, the distance of the inclined web (2) arrangement plus the net distance between two adjacent inclined webs (2) is used as the corrected arrangement distance. Then, the corrected arrangement distance is divided by the modulus of the inclined web (2) to calculate the number a of the inclined web (2) between two adjacent vertical webs (3). If the calculated a is not an integer, the number of inclined webs between two adjacent vertical webs (3) is determined by rounding down. Finally, the number of inclined webs between every two adjacent vertical webs (3) is calculated and then summed to obtain the number of inclined webs (2) in the device.

7. The apparatus according to claim 5, characterized in that, In step 4), the formula for calculating the total shear force of the device is: In v =mV1+nV2 Among them, V v V1 is the total shear force of the device; m is the number of vertical webs (3); V1 is the shear force on the vertical webs (3) obtained in step 2); n is the number of inclined web units; V2 is the shear force on the inclined web units obtained in step 2).

8. A method for measuring the working shear force of a seismic energy dissipator based on the device described in claim 7, characterized in that, include: First, determine the number of devices to be installed when measuring the shear force of the shear-type seismic energy dissipator to be measured based on the width of the node plate (9). Then, install all the devices, which are parallel to each other, and the deformation direction of each device is consistent with the deformation direction of the shear-type seismic energy dissipator. When the shear-type seismic energy dissipator deforms under seismic loading, the displacement change of each displacement measuring device at the current moment is obtained, and the average displacement change of all displacement measuring devices is calculated. Then based on the formula Obtain the shear force on the device , Multiplying the shear force by the number of shear force gauges deployed yields the shear force of the shear-type seismic energy dissipator, where, This refers to the shear deformation displacement of the inclined web element obtained in step 2).

9. The method according to claim 8, characterized in that, When the device is installed, the connection method between the top plate (1) and the node plate (9) is the same as the connection method between the end plate (10) and the node plate (9) of the shear-type seismic energy dissipator when the device is not installed, and the connection method between the bottom plate (4) and the end plate (10) of the shear-type seismic energy dissipator is the same as the connection method between the node plate (9) and the end plate (10) when the device is not installed; When connecting the node plate (9) to the top plate (1) and connecting the bottom plate (4) to the end plate (10) of the shear-type seismic energy dissipator, ensure that the vertical additional force generated by the shear-type seismic energy dissipator during operation is transmitted along the vertical web plate (3); and ensure that the shear force generated by the shear-type seismic energy dissipator during operation is transmitted evenly along the shear force action direction of the device.

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