Underground tunnel-foundation-earth surface frame structure earthquake test device and method

Abstract

The invention discloses an underground tunnel-foundation-earth surface frame structure earthquake test device and method, and relates to the technical field of civil engineering, and the underground tunnel-foundation-earth surface frame structure earthquake test device comprises a vibration table, a model box, an underground tunnel model, and an earth surface frame structure. The model box is fixedly installed on the vibration table, and the vibration table is used for inputting seismic waves to provide seismic power and drive the model box to vibrate. The model box is filled with foundation soil for testing, and the underground tunnel model is embedded in the foundation soil in the model box; the earth surface frame structure is a frame composed of a pile foundation, a raft plate, a cross beam, a panel and a stand column from bottom to top in sequence, and the pile foundation is embedded into foundation soil in the model box and located on one side or the upper portion of the underground tunnel model. According to the invention, the response process of the underground tunnel-foundation-surface frame structure coupling system under the earthquake action can be simulated, the time evolution and space distribution characteristics of the earthquake response of the coupling system can be determined, the influence rule of the earthquake wave characteristics on the earthquake response of the coupling system can be disclosed, and reference can be provided for the earthquake-resistant design and damping control of urban infrastructures.

Description

Technical Field

[0001] The present invention relates to the technical field of civil engineering, and particularly to an earthquake test device and method for an underground tunnel - foundation - surface frame structure. Background Art

[0002] In terms of spatial layout, subway tunnels frequently pass through or under some bustling commercial areas, venue gathering areas, and residential areas. The subway tunnels are connected to surface buildings through the foundation, forming an integrated coupling system.

[0003] It is recorded that cases of disasters caused by earthquakes in the coupling system occur frequently.

[0004] Under earthquake action, the existence of subway tunnels will change the propagation field of seismic waves, and thus affect the seismic response of the site foundation and surface buildings; similarly, the existence of surface buildings will also disturb the ground motion of the site where they are located. Since the subway tunnel is restricted by the surrounding rock and soil masses, its seismic deformation is controlled by the deformation of the surrounding rock and soil masses, so the existence of surface buildings will also affect the seismic response of the subway tunnel. Under earthquake action, the subway tunnel, foundation, and surface buildings form an interacting organic whole.

[0005] In recent years, the country has clearly proposed to build resilient cities, aiming to improve the city's ability to resist disasters, reduce disaster losses, and achieve rapid recovery of the city during disasters. As an important part of urban infrastructure, subway tunnels and surface buildings face the major disaster risk of earthquakes, and their seismic safety is related to the normal operation of the city and the development of the national economy. Therefore, the seismic performance evaluation and vibration reduction control of the subway tunnel - foundation - surface building coupling system have become difficult problems that urgently need to be solved in engineering.

[0006] In previous studies, relatively rich research results have been obtained for the two independent subsystems of the subway tunnel - foundation system and the foundation - surface building system. However, the comprehensive system seismic dynamic disaster problems of the subway underground structure - foundation - surface building system have only gradually attracted attention in recent years, and their seismic dynamic response characteristics and disaster mechanisms have not been clarified. It is urgent to build a test device and propose a test method. Summary of the Invention

[0007] In view of the problems existing in the above-mentioned earthquake test device and method for the underground tunnel - foundation - surface frame structure, the present invention is proposed.

[0008] To solve the above technical problems, the present invention provides the following technical solution: An underground tunnel - foundation - surface frame structure seismic test device, which includes a shaking table, a model box, an underground tunnel model, and a surface frame structure; the shaking table is used to input seismic waves to provide seismic power and drive the model box to vibrate, and the model box is fixedly installed on the shaking table; the model box is filled with foundation soil for the test, and the underground tunnel model is loaded in the foundation soil in the model box; the surface frame structure is a frame composed of a pile foundation, a raft, cross beams, a panel, and columns from bottom to top, and the pile foundation is embedded inside the model box and located on one side or above the underground tunnel model.

[0009] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: the upper opening of the model box is used for loading foundation soil, burying the underground tunnel model, and placing the pile foundation of the frame structure, the bottom is fixedly arranged on the shaking table, and the inner wall is successively pasted with a foam board and a rubber waterproof membrane.

[0010] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: the underground tunnel model and the surface frame structure are made according to a certain similarity relationship with the prototype.

[0011] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: the underground tunnel model and the surface frame structure are made of fine aggregate concrete, and the material of the foundation soil is sand.

[0012] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: the surface frame includes a plurality of cross beams and columns, the cross beams are arranged horizontally and columns are fixedly arranged at both ends thereof in the vertical direction; the cross beams are connected end to end to form a square and the panel is fixedly arranged in the middle of the cross beams and the columns.

[0013] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: a counterweight steel ring is fixedly arranged on the inner wall of the underground tunnel model, the steel ring is coaxial with the tunnel, and counterweight steel blocks are arranged on the panel of the surface frame structure.

[0014] As a preferred solution of the underground tunnel - foundation - surface frame structure seismic test device of the present invention, wherein: it further includes a monitoring and measuring system, the monitoring and measuring system includes sensors, data acquisition devices, and a computer, wherein the sensors are connected to the data acquisition devices, the data acquisition devices are connected to the computer, and the computer is loaded with a control system for data acquisition, analysis, and management.

[0015] As a preferred embodiment of the seismic test device for the underground tunnel - foundation - surface frame structure according to the present invention, wherein: the sensors include accelerometers, displacement gauges, earth pressure gauges, and pore water pressure gauges. The accelerometers are arranged axially at the springing near the surface frame structure side in the underground tunnel model, arranged vertically at intervals in the foundation soil, arranged at intervals on the columns of the surface frame structure, and arranged at intervals on the two side walls parallel to the vibration direction of the model box.

[0016] As a preferred embodiment of the seismic test device for the underground tunnel - foundation - surface frame structure according to the present invention, wherein: the displacement gauges are arranged at intervals at the intersection of the columns and the panels, the earth pressure gauges are arranged axially at intervals between the underground tunnel model and the pile foundation, and the pore water pressure gauges are arranged vertically at intervals in the foundation soil.

[0017] To solve the above technical problems, the present invention also provides the following technical solution: A method for the seismic test device of the underground tunnel - foundation - surface frame structure is based on the seismic test device of the underground tunnel - foundation - surface frame structure, including the following steps: Design the test, determine the test similarity ratio, manufacture the shear model box, foundation soil, underground tunnel model, and surface structure, and formulate the test loading system and the monitoring and measurement plan; Fix the model box above the shaking table, and paste the foam board and rubber film on the inner side wall of the model box in sequence to reduce the boundary effect and prevent the leakage of water in the foundation soil; According to the test plan, fill the foundation soil layer by layer in the model box, bury the underground tunnel model and the surface frame structure, and install sensors at the predetermined positions in the foundation soil, underground tunnel model, surface frame structure, and model box; Connect each sensor, data acquisition device, and computer terminal to ensure that the equipment and control system can all work normally; Conduct the white noise sweep test to obtain the dynamic characteristics such as the natural vibration frequency and damping ratio of the installed model system; Conduct the test, select seismic waves with different spectral characteristics, and input them step by step from small to large acceleration amplitude by the shaking table to apply seismic loads. During the process, measure the acceleration, displacement, earth pressure, and pore water pressure responses of the model system through the sensors, and transmit the collected signals to the data acquisition and analysis device, and then transmit them to the computer to obtain the dynamic response data of the coupled system; Analyze the test data obtained in the previous step to clarify the time evolution and spatial distribution characteristics of the seismic response, and reveal the influence law of the seismic wave characteristics on the seismic response of the coupled system.

[0018] The beneficial effects of the present invention are as follows: The shaking table in the test device of the present invention can provide earthquake ground motion inputs of multiple types and directions to simulate different earthquake scenarios. The model box can effectively overcome the boundary effects of traditional rigid model boxes and realize the simulation of the vibration shear deformation of foundation soil. The underground tunnel model and the surface frame structure in the test device of the present invention are designed and fabricated according to the structural characteristics, dimensional specifications, and performance parameters of the actual full-scale models, and can objectively reflect the seismic responses of the comprehensive seismic system. By arranging accelerometers, displacement gauges, pore water pressure gauges, and earth pressure gauges in the test device of the present invention, the dynamic responses of the underground tunnel, foundation, and surface frame structure under earthquake actions can be comprehensively obtained. The method of the present invention can obtain data such as accelerations, displacements, and pore water pressures of the underground tunnel-foundation-surface frame structure coupling system under different seismic spectrum characteristics and amplitude conditions. Through the analysis of the data, the time evolution and spatial distribution characteristics of the seismic dynamic responses of the coupling system, and the influence law of seismic wave characteristics on the seismic responses of the coupling system can be clarified, providing a reference for the seismic design and seismic reduction control of the coupling system. Description of the Drawings

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a scene diagram of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0021] Figure 2 It is an internal structure diagram of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0022] Figure 3 It is a schematic diagram of the scaled-down model of the underground tunnel of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0023] Figure 4 It is a frame structure diagram of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0024] Figure 5 It is a cross-sectional view of the beam and column of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0025] Figure 6 It is a side view of the pile foundation of the seismic test device for the underground tunnel-foundation-surface frame structure.

[0026] Figure 7Schematic diagram of the surface frame structure counterweight of the underground tunnel - foundation - surface frame structure seismic test device.

[0027] Figure 8 Schematic diagram of the underground tunnel model counterweight of the underground tunnel - foundation - surface frame structure seismic test device.

[0028] Figure 9 Top view of the monitoring point sensor layout of the underground tunnel - foundation - surface frame structure seismic test device.

[0029] Figure 10 Cross - sectional view of the monitoring point sensor layout of the underground tunnel - foundation - surface frame structure seismic test device. Specific implementation manners

[0030] To make the above - mentioned objects, features, and advantages of the present invention more obvious and understandable, the specific implementation manners of the present invention will be described in detail below with reference to the accompanying drawings of the specification.

[0031] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0032] Secondly, the so - called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it an embodiment that is separately or selectively mutually exclusive with other embodiments.

[0033] Embodiment 1

[0034] Refer to Figure 1 and Figure 2 , which is the first embodiment of the present invention. This embodiment provides an underground tunnel - foundation - surface frame structure seismic test device. The underground tunnel - foundation - surface frame structure seismic test device includes a shaking table 100, a model box 200, an underground tunnel model 300, and a surface frame structure 400.

[0035] Specifically, the model box 200 is fixedly installed on the shaking table 100. The shaking table 100 is used to input seismic waves to provide seismic power and drive the model box 200 to vibrate. The model box 200 is filled with the foundation soil 201 for the test, and the underground tunnel model 300 is buried in the foundation soil 201. The surface frame structure 400 is a frame composed of a pile foundation 401, a raft 402, cross beams 403, a panel 404, and columns 405 from bottom to top. The pile foundation 401 is embedded in the foundation soil 201 inside the model box 200 and is located on one side or above the underground tunnel model 300. The upper opening of the model box 200 is used to fill the foundation soil 201, bury the underground tunnel model 300, and place the pile foundation 401. The bottom is fixedly installed on the shaking table 100, and a foam board and a rubber waterproof membrane 202 are successively pasted on the inner wall.

[0036] Furthermore, the surface frame structure 400 includes a plurality of cross beams 403 and columns 405. The cross beams 403 are arranged horizontally, and columns 405 along the vertical direction are fixedly arranged at both ends thereof. The cross beams 403 are connected end to end to form a square, and the panel 404 is fixedly arranged in the middle of the cross beams 403 and columns 405. The cross beams 402 and columns 405 jointly enclose a cuboid grid frame, and the panel 404 is evenly and spacedly laid in the middle. The pile foundation 401 includes a plurality of fixed piles, all of which are fixedly connected to the bottom of the raft 402, and the bottom ends of the columns 405 are fixedly connected to the raft 402.

[0037] Among them, the underground tunnel - foundation - surface frame structure seismic test device further includes a monitoring and measurement system 500. The monitoring and measurement system 500 includes sensors 501, data acquisition devices 502, and a computer 503. Among them, the sensors 501 are connected to the data acquisition devices 502, and the data acquisition devices 502 are connected to the computer 503. The computer 503 is loaded with a control system for data acquisition, analysis, and management. The sensors 501 include accelerometers, displacement gauges, earth pressure gauges, and pore water pressure gauges. The accelerometers are axially arranged at the arch waist on the side close to the surface frame structure 400 in the underground tunnel model 300, are vertically spacedly arranged in the foundation soil 201, are spacedly arranged on the columns 405 of the surface frame structure 400, and are spacedly arranged on the two side walls parallel to the vibration direction of the model box 200. The displacement gauges are spacedly arranged at the intersection positions of the columns 405 and the panel 404. The earth pressure gauges are axially spacedly arranged between the underground tunnel model 300 and the pile foundation 401. The pore water pressure gauges are vertically spacedly arranged in the foundation soil 201.

[0038] Preferably, the similarity ratios of the underground tunnel model 300 and the surface frame structure 400 to the original size are both 1 / 10.

[0039] Preferably, the underground tunnel model 300 and the surface frame structure 400 are made of particulate concrete, and the material of the foundation soil 201 is sandy soil with a density of 65%.

[0040] Preferably, a steel ring is fixedly arranged on the inner wall of the underground tunnel model 300 to meet the weight requirement, and the steel ring is coaxial with the tunnel.

[0041] Preferably, steel blocks are arranged on the panel 404 of the surface frame structure 400 to meet the weight requirement.

[0042] It should be noted that the model box 200 is a laminated shear model box, which can effectively overcome the boundary effect of the traditional rigid model box and realize the simulation of the vibration shear deformation of the foundation soil 201.

[0043] Embodiment 2

[0044] Refer to Figures 3 to 8 , which is the second embodiment of the present invention, and this embodiment is based on the previous embodiment.

[0045] Specifically, the shaking table 100 has three directions and six degrees of freedom, and the tabletop size is 6.0 m × 4.0 m, and it can simulate any seismic wave below 50 Hz. According to the tabletop size of the shaking table 100, the outer size of the model box 200 is designed to be 2.9 m × 2 m × 1.9 m (length × width × height), and the inner net size of the box is designed to be 2.7 m × 1.8 m × 1.9 m, and it is assembled by stacking 16 layers of steel pipe frames. Each layer of the frame is welded by square steel pipes with a side length of 10 cm.

[0046] Table 1 shows the experimental similarity relationship and similarity ratio. Taking the length l, density ρ, and elastic modulus E as the basic unknowns, other physical quantities are determined by these three quantities. Considering the bearing capacity of the shaking table 100 and the size of the model box 200 comprehensively, the experimental geometric size similarity ratio is taken as λ l = 1 / 10; The particulate concrete is used to make the underground tunnel model 300 and the surface frame structure 400, and its elastic modulus is about 1 / 3 of the actual concrete. Therefore, the elastic modulus similarity ratio λ E = 1 / 3. The equivalent density similarity ratio of the underground tunnel model 300 and the surface frame structure 400 is λ ρ = λ E / λ l = 10 / 3. The counterweight of the surface frame structure 400 is realized by uniformly placing artificial steel blocks on each layer of the panel 404, and the counterweight of the underground tunnel model 300 is realized by placing artificial steel rings inside the tunnel.

[0047] Table 1 Similarity relationship and similarity ratio of each physical quantity

[0048]

[0049] Furthermore, since the prototype of the foundation soil 201 is a soft soil foundation, sand is selected as the similar material. The effects of different dry densities on the shear wave velocity and shear modulus of sand are studied, and the sand parameters meeting the requirements of soft foundation simulation are given. The sand compactness is determined to be 65%, and the dry density is determined to be 1.64 g / cm 3 .

[0050] As Figure 3 shown, the underground tunnel model 300 is the most common subway tunnel in the project. The outer diameter of the tunnel is 6 m, the inner diameter is 5.4 m, the wall thickness is 0.3 m, and the longitudinal length is 18 m. According to the geometric similarity ratio λ l = 1 / 10, the dimensions of the tunnel model are designed as an outer diameter of 600 mm, an inner diameter of 540 mm, a wall thickness of 30 mm, and a longitudinal length of 1.8 m. A total of 12 sections are made, each section is 150 mm, and epoxy resin rebar adhesive is used to connect each section into a whole during the test.

[0051] As Figures 4 to 6 shown, the surface frame structure 400 is a double-span and double-opening reinforced concrete frame structure. The plane size of the structure is 8 m × 8 m, the storey height is 3 m, and there are 10 storeys in total. The cross-sectional size of the column 405 is 0.5 m × 0.5 m. The cross beam 403 includes main beams and secondary beams. The cross-sectional size of the main beam is 0.3 m × 0.4 m, and the cross-sectional size of the secondary beam is 0.2 m × 0.3 m. The thickness of the floor slab 404 is 0.2 m. The plane size of the raft slab 402 is 10 m × 10 m, and the thickness is 1 m. The foundation form is a cast-in-place pile 401, the outer diameter of the pile body is 0.8 m, the pile length is 12 m, and the pile spacing is 2 m. According to the geometric similarity ratio λ l = 1 / 10, the dimensions of the frame structure model are designed as follows: the floor plane size is 800 mm × 800 mm, the storey height is 300 mm, and there are 10 storeys in total. The thickness of the floor slab 404 is 20 mm. The cross-sectional size of the column 405 is 50 mm × 50 mm. The cross-sectional size of the main beam in the cross beam 403 is 30 mm × 40 mm, and the cross-sectional size of the secondary beam is 20 mm × 30 mm. The plane size of the raft slab 402 is 1000 mm × 1000 mm, and the thickness is 100 mm. The diameter of the pile foundation 401 is 80 mm, the pile length is 12000 mm, and the pile spacing is 200 mm.

[0052] Table 2 gives the calculation process of the counterweights required for the surface frame structure 400 and the underground tunnel model 300. It can be seen that the counterweight required for the surface frame structure 400 is 1.84 t, and 184 kg of counterweight is required on each floor slab. After calculation, placing 2 steel blocks with a size of 0.8 m × 0.3 m × 0.05 m on each floor can meet the requirements. In order to prevent the steel blocks from swaying during the test and causing potential safety hazards, the long sides of the steel blocks are placed perpendicular to the vibration direction, and the steel blocks are fixed to the floor slab with steel wires, as Figure 7As shown, the counterweight required for the tunnel structure is 0.56 t, and each section of the tunnel requires a counterweight of 46.7 kg. After calculation, placing steel rings with an outer diameter of 540 mm, an inner diameter of 490 mm, and a wall thickness of 25 mm inside each section of the tunnel model can meet the requirements, as Figure 8 shown.

[0053] Table 2 Calculation process of the counterweight for the surface frame structure and the underground tunnel model

[0054]

[0055] Example 3

[0056] Refer to Figure 9 and Figure 10 , which is the third embodiment of the present invention. This embodiment provides a method for an underground tunnel - foundation - surface frame structure seismic test device.

[0057] Specifically, first determine the test similarity ratio, fabricate the shear model box 200, foundation soil 201, underground tunnel model 300, and surface frame structure 400, and formulate the test loading system and the monitoring and measurement plan; fix the model box 200 above the shaking table 100, and sequentially paste foam boards and rubber membranes 202 on the inner side walls of the model box 200 to reduce the boundary effect and prevent the leakage of water in the foundation soil 201; according to the test plan, layer by layer fill the foundation soil 201 in the model box 200, bury the underground tunnel model 300 and the surface frame structure 400, and install sensors at predetermined positions in the foundation soil 201, the underground tunnel model 300, the surface frame structure 400, and the model box 200; connect each sensor 501, data acquisition device 502, and computer 503 to ensure that the equipment and the control system can all work properly; conduct the white noise sweep test, that is, use white noise sweep with an amplitude less than or equal to 0.05 g to obtain the dynamic characteristics such as the natural vibration frequency and damping ratio of the installed model system; conduct the test, that is, select seismic waves with different spectral characteristics, and input them step by step from small to large acceleration amplitude by the shaking table 100 to apply seismic loads. During the process, measure the acceleration, displacement, soil pressure, and pore water pressure responses of the model system through the sensor 501, and transmit the collected signals to the data acquisition and analysis device 502, and then transfer them to the computer 503 to obtain the dynamic response data of the coupled system; analyze the test data obtained in the previous step, clarify the time evolution and spatial distribution characteristics of the seismic response, and reveal the influence law of the seismic wave characteristics on the seismic response of the coupled system.

[0058] Among them, accelerometers (numbered: A1 - A11) are installed in the underground tunnel model 300, accelerometers (numbered: A12 - A19), earth pressure gauges (P1 - P11), and pore water pressure gauges (W1 - W4) are installed in the foundation soil 201, and accelerometers (A20 - A35) and displacement gauges (D1 - D16) are installed at predetermined positions of the surface frame structure 400 and the model box 200.

[0059] Among them, the loading regime is shown in Table 3. The loading waveforms include two types, namely white noise and seismic waves. Among them, the seismic waves are respectively selected as the low - frequency wave - Kobe wave, the medium - frequency wave - El Centro wave, and the high - frequency wave - Taft wave. The time step of the acceleration time history of the three prototype seismic waves is 0.02 s. According to the time similarity ratio the time step is adjusted to 0.0063 s. Since the acceleration similarity ratio is 1, the acceleration peak remains unchanged after amplitude modulation.

[0060] According to the order of the peak values of the loading waveforms from small to large, the loading process is divided into 6 levels. In levels L1 - L5, each level contains 4 loading waveforms, that is, 1 white noise and 3 seismic waves. The seismic waves within each level adopt the same acceleration peak value; the L6 - level loading only contains white noise. The first working condition of each level of loading is white noise, and the acceleration peak value is 0.05 g; the step difference of the acceleration peak value of the seismic waves is 0.2 g, and the maximum loading reaches 1.0 g.

[0061] Table 3 Loading conditions of the shaking table model test

[0062]

[0063] During the seismic wave loading process, the responses such as the acceleration, displacement, and pore water pressure of the model system are measured by sensors, and the collected signals are transmitted to the data acquisition device 502, and then transmitted to the computer 503 to obtain the dynamic response data of the test system.

[0064] By analyzing the monitored data, the time evolution and spatial distribution laws of the seismic response of the underground tunnel - foundation - surface frame structure coupling system can be clarified, and the influence laws of the seismic wave characteristics on the seismic response of the system can be revealed.

[0065] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. An underground tunnel-foundation-surface frame structure seismic test device, characterized in that: Including shaking table, model box, underground tunnel model, surface frame structure; The vibration table is used to input seismic waves to provide seismic power, thereby driving the model box to vibrate, and the model box is fixedly mounted on the vibration table; The model box is filled with test foundation soil, and the underground tunnel model is filled in the foundation soil in the model box; The surface frame structure is a frame composed of pile foundation, raft, beam, panel and column from bottom to top. The pile foundation is embedded in the foundation soil inside the model box and is located on one side or above the underground tunnel model.

2. The underground tunnel-foundation-surface frame structure seismic test device according to claim 1, characterized in that: The upper opening of the model box is used for filling foundation soil, burying the underground tunnel model, and placing the frame structure pile foundation. The bottom is fixedly installed on the vibration table, and the inner wall is sequentially pasted with a foam board and a rubber waterproof membrane.

3. The underground tunnel-foundation-surface frame structure seismic test device according to claim 2, characterized in that: The underground tunnel model and the surface frame structure are made according to a prototype with a certain similarity relationship.

4. The underground tunnel-foundation-surface frame structure earthquake test device according to claim 3, characterized in that: The underground tunnel model and the surface frame structure are made of micro-concrete, and the material of the foundation soil is sand.

5. The underground tunnel-foundation-surface frame structure earthquake test device according to claim 4, characterized in that: The surface frame includes a plurality of beams and columns. The beams are arranged in the horizontal direction and columns in the vertical direction are fixedly arranged at both ends of the beams. The beams are connected end to end to form a square and the panel is fixedly arranged between the beams and the columns.

6. The underground tunnel-foundation-surface frame structure seismic test device according to claim 5, characterized in that: A counterweight steel ring is also fixedly arranged on the inner wall of the underground tunnel model, and the steel ring is coaxial with the tunnel. A counterweight steel block is arranged on the panel of the surface frame structure.

7. The underground tunnel-foundation-surface frame structure seismic test device according to claim 6, characterized in that: It also includes monitoring and measurement systems. The monitoring and measuring system includes a sensor, a data acquisition device and a computer, wherein the sensor is connected to the data acquisition device, the data acquisition device is connected to the computer, and the computer is equipped with a control system for data acquisition, analysis and management.

8. The underground tunnel-foundation-surface frame structure seismic test device according to claim 7, characterized in that: The sensors include accelerometers, displacement meters, soil pressure meters and pore water pressure meters. The accelerometers are axially arranged at the waist of the underground tunnel model close to one side of the surface frame structure, are vertically spaced in the foundation soil, are spaced on the columns on the surface frame structure, and are spaced on the side walls at both ends parallel to the vibration direction on the model box.

9. The underground tunnel-foundation-surface frame structure seismic test device according to claim 8, characterized in that: The displacement meters are arranged at intervals at the intersection of the column and the panel, the soil pressure meters are arranged at intervals along the axial direction of the underground tunnel between the underground tunnel model and the pile foundation, and the pore water pressure meters are arranged at intervals along the vertical direction in the foundation soil.

10. A method for an underground tunnel-foundation-surface frame structure seismic test device, characterized in that: The underground tunnel-foundation-surface frame structure seismic test device according to claim 1 comprises the following steps: Design the test, determine the test similarity ratio, make the shear model box, foundation soil, underground tunnel model and surface structure, and formulate the test loading system and monitoring measurement plan; Fix the model box on the vibration table, and stick the foam board and rubber film on the inner wall of the model box in sequence to reduce the boundary effect and prevent water leakage in the foundation soil; According to the test plan, the model box is filled with foundation soil layer by layer, the underground tunnel model and the surface frame structure are buried, and sensors are installed in the foundation soil, the underground tunnel model, the surface frame structure and the predetermined positions of the model box; Connect various sensors, data acquisition equipment and computer terminals to ensure that the equipment and control systems can work properly; Conduct white noise frequency sweep test to obtain dynamic characteristics such as natural frequency and damping ratio of the installed model system; The experiment was carried out by selecting seismic waves with different spectral characteristics. The vibration table inputted the acceleration amplitude step by step from small to large to apply the seismic load. During the process, the acceleration, displacement, soil pressure and pore water pressure response of the model system were measured by sensors, and the collected signals were transmitted to the data acquisition and analysis equipment, and then to the computer to obtain the dynamic response data of the coupling system. Analyze the test data obtained in the previous step, clarify the time evolution and spatial distribution characteristics of the seismic response, and reveal the influence of seismic wave characteristics on the seismic response of the coupled system.

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