Multifunctional device for earth and rockfill dam vibration table model test and test method

Abstract

The invention provides a multifunctional device for an earth and rockfill dam vibration table model test, and relates to the technical field of earth and rockfill dam vibration table model tests.The multifunctional device comprises a model box, an earth and rockfill dam model filling mold and a data acquisition system, and the earth and rockfill dam model filling mold comprises a mold frame, third T-shaped steel, first T-shaped steel, a baffle and a rectangular steel pipe; the data acquisition system comprises a high-definition digital single lens reflex, a high-speed camera, a picture acquisition and storage workstation, a computer, an optical fiber demodulator, an acceleration sensor, a fiber grating sensor and an acceleration acquisition board; through single-channel synchronous measurement of a plurality of sensors, not only is the measurement efficiency improved, but also the interference of sensor burying on an earth and rockfill dam model is remarkably reduced, the displacement of any point in an observation surface at any moment in a test can be measured by utilizing a P IV measurement technology, and the complete process from deformation to damage of a side slope is comprehensively recorded; important support is provided for deeply researching the earth and rockfill dam side slope damage mechanism under the earthquake action.

Description

Technical Field

[0001] The invention relates to the technical field of earth-rock dam shaking table model testing, in particular to a multifunctional device and a testing method for earth-rock dam shaking table model testing. Background Art

[0002] An earth-rock dam generally refers to a retaining dam constructed from locally sourced earth, stone, or a mixture of these materials through dumping, filling, and compaction. When the dam's body is primarily composed of earth and gravel, it's called an earth dam; when it's primarily composed of slag, pebbles, or blasted stone, it's called a rockfill dam. When both types of local materials make up a significant proportion, it's called an earth-rock dam. Earth-rock dams are the oldest type of dam.

[0003] Given the potential for extreme events such as dam failure or overtopping of high dams and large reservoirs under strong earthquakes, the chain of disasters poses a serious threat to the economy and the safety of life and property. Therefore, it is particularly important to thoroughly evaluate the seismic performance of earth-rock dams and explore their damage mechanisms. Field surveys, as a method of directly obtaining earthquake damage data, are limited by the scarcity of dams that have experienced strong earthquakes and the limitations of the measured data types, making it difficult to deeply analyze the earthquake damage mechanisms. Numerical simulations still face many challenges in accurately describing the complexity of dam construction materials and seismic input, which may lead to deviations between the calculated results and the actual situation. Model tests, with their unique advantages of flexibility, repeatability and real-time observation of the damage evolution process, have become an important means in recent years to predict the seismic response of high earth-rock dams, verify seismic resistance theories and the accuracy of numerical simulations.

[0004] In current shaking table model tests of earth-rockfill dams, model construction is usually achieved using manual layered compaction technology. However, due to the large size and high density requirements of the model, it relies on heavy objects for compaction, which poses challenges to the integrity and stability of the model and easily affects the accuracy of monitoring data.

[0005] At the same time, traditional displacement monitoring methods based on sensors and markers have defects such as low accuracy and poor efficiency. They cannot capture the gradual evolution process of large-scale soil. In addition, due to the low strength and small elastic modulus of the panel and core wall structures in model tests that meet the similarity principle, traditional strain gauges are difficult to directly and firmly attach to the surface of the structure to be tested and are extremely susceptible to the strong electromagnetic interference generated by the earthquake simulation system. Summary of the Invention

[0006] In order to overcome the shortcomings of the existing technology, the embodiments of the present application provide a multifunctional device and testing method for shaking table model tests of earth-rock dams. Through single-channel synchronous measurement of multiple sensors, not only the measurement efficiency is improved, but also the interference of sensor burial on the earth-rock dam model is significantly reduced. The PIV measurement technology can accurately measure the displacement of any point within the observation surface at any time in large-scale shaking table model tests, and comprehensively record the complete process of slope deformation to destruction, providing important support for in-depth research on the failure mechanism of earth-rock dam slopes under earthquakes.

[0007] The technical solution adopted by the embodiment of the present application to solve the technical problem is:

[0008] A multifunctional device and testing method for a shaking table model test of an earth-rock dam, comprising a model box with a bottom plate provided at the bottom;

[0009] Earth-rockfill dam model filling mold;

[0010] Data acquisition system;

[0011] The earth-rock dam model filling mold is sleeved inside the model box from top to bottom, and the earth-rock dam model filling mold includes a mold frame, and third T-shaped steels are provided at the two long sides of the inner side of the top of the mold frame, and the first T-shaped steels are provided at both ends of the two third T-shaped steels. Two baffles are provided on the inner side of the bottom of the mold frame, and the two baffles are symmetrically arranged and form a trapezoid with the top and bottom horizontal planes. Rectangular steel pipes are provided on the two long sides of the top surface of the baffles;

[0012] The data acquisition system includes a high-definition digital SLR camera and a high-speed camera, which are connected to an image acquisition and storage workstation via wireless signal transmission, and the image acquisition and storage workstation is connected to a computer via wireless signal transmission. The computer is also connected to an optical fiber demodulator and an acceleration sensor via a data cable, and the optical fiber demodulator is connected to a fiber grating sensor via a data cable, and the acceleration sensor is connected to an acceleration acquisition board via a data cable.

[0013] In one possible implementation, the top of the model box is open, the front of the model box is made of a transparent acrylic plate material, and the remaining three sides are made of a steel plate material, and the bottom plate is connected to the vibration table by high-strength bolts.

[0014] In one possible implementation, the earth-rock dam model is divided into a core-wall earth-rock dam or a panel-faced earth-rock dam. When the earth-rock dam model is a core-wall earth-rock dam, the fiber grating sensors are divided into two groups and vertically arranged on both sides of the central axis of the core wall. When the earth-rock dam model is a panel-faced earth-rock dam, the fiber grating sensors are arranged at the central axis of the top surface of the panel, and during the water addition test, the fiber grating sensors are located in the upper middle position of the panel surface.

[0015] In one possible implementation, the fiber Bragg grating sensor is a strain sensor, which consists of a fiber Bragg grating and two clamping components. A plastic tube is provided on the outside of the fiber Bragg grating, and end supports are provided at both ends of the plastic tube. The fiber Bragg grating passes through the inside of the two end supports.

[0016] In a possible implementation, a plurality of acceleration sensors are provided and arranged in a grid pattern inside the earth-rock dam model.

[0017] In one possible implementation, the first T-shaped steel is connected to the inner wall of the mold box by high-strength bolts, a strip-shaped hollow hole is opened inside one side of the first T-shaped steel, and the bolt passes through the long hollow hole to connect with the third T-shaped steel, and the third T-shaped steel is supported by the two first T-shaped steels to move up and down on the inner side of the mold frame.

[0018] In one possible implementation, strip-shaped hollow holes are reserved inside the long side of the bottom of the mold frame and inside the third T-shaped steel. The two ends of the two rectangular steel tubes are respectively connected to the inside of the two strip-shaped hollow holes. The two rectangular steel tubes are guided by the strip-shaped hollow holes on the mold frame and the third T-shaped steel to move closer to or away from each other.

[0019] In a possible implementation, the baffle is a rigid plate and is connected to the rectangular steel pipe through a mortise and tenon structure.

[0020] In a possible implementation, the rectangular steel pipe includes a guide groove, a steel pipe strip is provided inside the guide groove, and an opening is provided at a corner of the guide groove.

[0021] A testing method for a shaking table model test of an earth-rock dam, comprising:

[0022] S1. Fix the model box and the vibration table together with bolts;

[0023] S2. Use bolts to fix the first T-shaped steel and the mold frame to the inner wall of the mold box respectively. According to the slope ratio of the earth-rock dam slope required by the test, use bolts to connect the third T-shaped steel and the first T-shaped steel. Use bolts to connect the two ends of the rectangular steel tube to the strip-shaped hollow hole at the bottom of the mold frame and the strip-shaped hollow hole inside the third T-shaped steel respectively.

[0024] S3. Based on the height of the core wall, place the required number of baffles from above the two rectangular steel tubes through the structure on top of the rectangular steel tubes. Once both sides are firmly fixed, add clay and tamp until the model reaches the required density. Repeat the above steps until the filling is complete.

[0025] S4. Remove the rectangular steel pipe and baffles. After the core wall is cured, dig a groove on the surface of the core wall's central axis for installing the fiber Bragg grating sensor. Place the image acquisition and storage workstation in the groove and fill it with test clay for compaction.

[0026] S5. Adjust the positions of the rectangular steel tube and the third T-shaped steel to ensure that the angle of the rectangular steel tube meets the slope ratio required by the earth-rock dam model. Repeat step S3, replacing the clay material with rockfill material. During the filling process, bury acceleration sensors at preset positions. After the filling is completed, remove the rectangular steel tube, the third T-shaped steel, and the baffle.

[0027] S6. Place a high-definition digital SLR camera in the middle of one side of the acrylic plate of the model box. Place the tripod on the vibration-isolating rubber layer. Place a high-speed camera above the model box. Connect all equipment and prepare to start the test.

[0028] S7. Simulating an earthquake, the earth-rock dam model begins to deform under the action of the earthquake load. During this process, the fiber grating sensor records the strain data of the core wall, the fiber optic interrogator analyzes the strain data transmitted by the fiber grating sensor through the optical fiber, and the high-definition digital SLR camera continuously captures the position changes of any point on the observation surface at any time. The acceleration acquisition board analyzes the acceleration data collected by the acceleration sensor in the earth-rock dam model during the test. Simultaneously, the flow characteristics of the downstream rockfill material are recorded by a high-speed camera.

[0029] S8. The image acquisition and storage workstation transmits the collected photos to the computer. The photos taken by the high-definition digital SLR camera are processed using PIV technology to obtain the displacement field of the earth-rock dam slope within the entire observation surface. The processed photos are post-processed to obtain a rich picture of the complete process from slope deformation to failure.

[0030] S9. Store test data on the computer and dismantle and clean the equipment.

[0031] The beneficial effects of this application are:

[0032] First, this solution allows for flexible construction of slopes at any angle by adjusting the position of components, effectively reducing the impact of human or accidental factors on the quality of earth-rock dam slope filling during the filling process, improving test accuracy and model quality. The application of fiber Bragg grating sensors on the core wall and face plate enables high-precision measurement of strain in the face plate and core wall of the earth-rock dam model.

[0033] Second, in this scheme, the single-channel synchronous measurement of multiple sensors not only improves the measurement efficiency, but also significantly reduces the interference of sensor burial on the earth-rock dam model. The PIV measurement technology can accurately measure the displacement of any point in the observation surface at any time in the large-scale shaking table model test, and comprehensively record the complete process from deformation to destruction of the slope, providing important support for in-depth research on the failure mechanism of earth-rock dam slopes under earthquake action. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is one of the overall structural schematic diagrams of the earth-rock dam model test device of the present invention;

[0035] Figure 2 This is the second schematic diagram of the overall structure of the earth-rock dam model test device of the present invention;

[0036] Figure 3 Schematic diagram of the internal structure of the model box of the present invention;

[0037] Figure 4 It is a cross-sectional view of the model box of the present invention;

[0038] Figure 5 It is a structural schematic diagram of the present invention;

[0039] Figure 6 Schematic diagram of the structure of the grating optical fiber of the present invention;

[0040] Figure 7 This is a schematic structural diagram of the first T-shaped steel of the present invention;

[0041] Figure 8 It is a structural block diagram of the earth-rock dam model test system of the present invention.

[0042] Figure numerals: 1. model box; 2. fiber optic demodulator; 3. computer; 4. high-definition digital SLR camera; 5. picture acquisition and storage workstation; 6. fiber optic Bragg grating sensor; 7. acceleration sensor; 8. acceleration acquisition board; 9. bottom plate; 10. data cable; 11. first T-shaped steel; 12. rectangular steel pipe; 121. guide groove; 122. opening; 123. steel pipe strip; 13. mold frame; 14. third T-shaped steel; 15. baffle; 16. plastic pipe; 17. end support; 18. high-speed camera; 19. earth-rock dam model; 20. panel. DETAILED DESCRIPTION

[0043] The technical solution in the embodiments of the present application is to solve the problems of the above-mentioned background technology, and the overall idea is as follows:

[0044] Example 1:

[0045] This embodiment introduces the specific structure of a multifunctional device for earth-rock dam shaking table model test. Figures 1-8 As shown, it includes a model box 1 with a bottom plate 9 at the bottom, an earth-rock dam model filling mold and a data acquisition system. The earth-rock dam model filling mold is sleeved inside the model box 1 from top to bottom. The earth-rock dam model filling mold includes a mold frame 13. Third T-shaped steels 14 are provided at the two long sides of the inner side of the top of the mold frame 13. First T-shaped steels 11 are provided at both ends of the two third T-shaped steels 14. Two baffles 15 are provided on the inner side of the bottom of the mold frame 13. The two baffles 15 are symmetrically arranged and form a trapezoid with the top and bottom horizontal planes. Rectangular steel pipes 12 are provided on the two long sides of the top surface of the baffle 15.

[0046] like Figure 8 As shown, the data acquisition system includes a high-definition digital SLR camera 4 and a high-speed camera 18. The high-definition digital SLR camera 4 and the high-speed camera 18 are connected to an image acquisition and storage workstation 5 by wireless signal transmission. The image acquisition and storage workstation 5 is connected to a computer 3 by wireless signal transmission. The computer 3 is also connected to a fiber optic demodulator 2 and an acceleration sensor 7 via a data line 10. A plurality of acceleration sensors 7 are provided and arranged in a grid pattern inside the earth-rock dam model 19. The fiber optic demodulator 2 is connected to a fiber grating sensor 6 via a data line 10. The acceleration sensor 7 is connected to an acceleration acquisition board 8 via a data line 10.

[0047] The model box and the shaking table are fixed together by bolts to ensure that the seismic waves output by the shaking table can be effectively transmitted to the earth-rock dam model 19. The displacement of any point on the observation surface of the earth-rock dam model 19 at any time is recorded by a high-definition digital SLR camera 4. The captured images are processed by the image acquisition and storage workstation 5 and converted into visual data using particle image velocimetry (PIV). This effectively captures the entire process of the model from deformation and settlement to failure during the test.

[0048] At the same time, the fiber Bragg grating sensor 6 is connected in series through optical fibers to achieve single-channel multi-point synchronous measurement. The fiber Bragg grating sensor 6 after series connection is connected to the acceleration acquisition board 8 through a data line, which can automatically collect the strain data of the core wall or panel with high precision and stability.

[0049] The height of the high-speed camera 18 is adjusted using a tripod mounted on a multi-layered, seismically isolated rubber base to minimize interference with the filming process during vibration table operation. The dynamic response characteristics of the rockfill material are measured using an acceleration sensor 7 embedded within the earth-rock dam model 19. This acceleration sensor 7 is connected to an acceleration acquisition board 8 via a data cable. The acceleration acquisition board 8 and the fiber optic demodulator 2 are then connected to a computer 3 via a data cable 10, enabling automatic data collection and recording throughout the entire test process.

[0050] Secondly, the earth-rock dam model 19 is divided into a core-wall earth-rock dam or a panel-20 earth-rock dam. When the earth-rock dam model 19 is a core-wall earth-rock dam, the fiber Bragg grating sensors 6 are divided into two groups and vertically arranged on both sides of the central axis of the core wall. When the earth-rock dam model 19 is a panel-20 earth-rock dam, the fiber Bragg grating sensors 6 are arranged at the central axis of the surface of the panel 20. During the water addition test, the fiber Bragg grating sensors 6 are located in the upper middle position of the surface of the panel 20.

[0051] Furthermore, by making the top of the model box 1 open, the front of the model box 1 is made of a transparent acrylic plate material, and the remaining three sides are made of a steel plate material, which can support the high-definition digital SLR camera 4 and the high-speed camera 18 to perform image acquisition work;

[0052] At the same time, since the model box 1 has a large length and a high height, in order to avoid the box body deformation during the construction of the model, the outer side of the model box 1 is reinforced by laying steel pipes;

[0053] Furthermore, the fiber Bragg grating sensor 6 is a strain sensor, consisting of a fiber Bragg grating and two clamping components. A plastic tube 16 is provided on the outside of the fiber Bragg grating, and end supports 17 are provided at both ends of the plastic tube 16. The fiber Bragg grating passes through the interior of the two end supports 17, which can prevent the adhesive from directly contacting the fiber Bragg grating, thereby reducing possible damage. The clamping components have a rectangular structure and are usually made of steel pipe or other rigid materials. Each surface is polished to increase the friction between the sensor and the measured structure to ensure that the sensor is tightly integrated with the structure. The fiber Bragg grating sensor realizes multi-point synchronous measurement through optical fiber series connection;

[0054] like Figure 4 、 Figure 5 and Figure 7 As shown, the first T-shaped steel 11 is connected to the inner wall of the mold box 1 by high-strength bolts. A strip-shaped hollow hole is opened inside one side of the first T-shaped steel 11, and the bolt passes through the long hollow hole to connect with the third T-shaped steel 14. The third T-shaped steel 14 is supported by the two first T-shaped steels 11 and guided by them to move up and down on the inner side of the mold frame 13;

[0055] Among them, the third T-shaped steel 14 and the first T-shaped steel 11 are designed the same, only the length is different. The length of the third T-shaped steel 14 is equal to the length of the inner side of the model box, and the length of the first T-shaped steel 11 is preferably half the height of the model box. Strip hollow holes are reserved inside the long side of the bottom of the mold frame 13 and inside the third T-shaped steel 14. Both ends of the two rectangular steel tubes 12 are respectively connected to the inside of the two strip hollow holes. The two rectangular steel tubes 12 are guided by the strip hollow holes on the mold frame 13 and the third T-shaped steel 14 to move closer to or away from each other. The long strip hollow design can adjust the height of the third T-shaped steel 14 as needed, thereby changing the angle of the rectangular steel tube 12 to meet the requirements of different earth-rock dam slope angles;

[0056] In some examples, the rectangular steel pipe 12 includes a guide groove 121 , a steel pipe strip 123 is formed inside the guide groove 121 , and an opening 122 is formed at one corner of the guide groove 121 ;

[0057] Among them, the baffle 15 is a rigid plate and is connected to the rectangular steel pipe 12 by a mortise and tenon structure. Semi-cylindrical strips are integrally formed on the two long sides of the baffle 15. The semi-cylindrical strips are slidably connected to the inside of the steel pipe strip 123. The width of the baffle 15 is designed according to the layered filling height of the earth-rock dam model. The baffle 15 is inserted into the steel pipe strip 123 through the opening 122, and the baffle 15 is moved to the bottom of the model box 1 so that it contacts the bottom plate 9. After each filling and tamping is completed, the next baffle 15 is inserted into the rectangular steel pipe 12 to ensure that the effect of the weight during tamping does not affect the stability of the slope.

[0058] Example 2:

[0059] Based on Example 1, this example introduces a testing method for a shaking table model test of an earth-rock dam, including:

[0060] At the same time, since temperature and humidity have a significant impact on the sensitivity of the fiber Bragg grating sensor 6, which may lead to deviations in the experimental data and even sensor failure in extreme cases, these factors should be fully considered during the assembly and burial process. When the earth-rock dam model is layered and artificially compacted, the fiber Bragg grating sensor 6 may be reversed or shifted and deviate from the predetermined position.

[0061] Therefore, based on the fact that the earth-rock dam test lasts only tens of seconds, the influence of temperature can be ignored and only the humidity factor needs to be considered. First, the two fiber grating sensors 6 are connected in series through optical fibers, and a layer of glass glue is evenly coated at the connection between the optical fibers and the fiber grating sensors 6; then, starting from the connection, all connection parts are wrapped with insulating tape to ensure sealing. The buried work of the sensor will be carried out after the core wall is made and initially maintained. The specific method is to open a groove slightly larger than the fiber grating sensor on the surface of the core wall, place the sensor in it, and fill and compact it with test clay to ensure its stable position and the accuracy of data acquisition;

[0062] The high-definition digital SLR camera 4 captures images during the experiment, effectively capturing the entire process of deformation, settlement, and final failure of the earth-rock dam model during vibration, and obtaining detailed data on the deformation and failure of the earth-rock dam slope. The high-speed camera 18 is used to record the failure characteristics of the rockfill on the downstream slope, providing further analysis of the dynamic behavior of the downstream slope.

[0063] In the above operation, the size of the earth-rock dam model is determined according to the size of the vibration table and the load parameters, the length of the components and the number of sensors are determined using the actual model size, the layout positions of the acceleration sensor 7 and the fiber Bragg grating sensor 6 are determined according to the specific test requirements, and a test plan that meets the test requirements is formulated; according to the size of the vibration table and the load parameters, the model box model size of this embodiment is preferably 4m×0.8m×1.5m long×width×height, and the test conditions are all empty warehouses. Sensor layout is as follows Figure 1 and Figure 2 shown.

[0064] Take the model core dam as an example, with a dam height of 1m, upstream and downstream slopes of 1:1.9 and 1:1.8 respectively, a dam crest width of 0.1m, a core wall height of 0.95m, and top and bottom widths of 0.05m and 0.4m respectively. Figure 2 , the test steps are as follows:

[0065] S1. Fix the model box 1 and the shaking table together with bolts to ensure that the seismic waves output by the shaking table can be effectively transmitted to the earth-rock dam;

[0066] S2. Use bolts to fix the first T-shaped steel 11 and the mold frame 13 to the inner wall of the mold box 1 respectively. According to the slope ratio of the earth-rock dam slope required by the test, use bolts to connect the third T-shaped steel 14 and the first T-shaped steel 11. Use bolts to connect the two ends of the rectangular steel tube 12 to the strip-shaped hollow hole at the bottom of the mold frame 13 and the strip-shaped hollow hole inside the third T-shaped steel 14 respectively.

[0067] S3. Based on the height of the core wall, place the required number of baffles 15 from above the two rectangular steel tubes 12 through the structure 102 on top of the rectangular steel tubes 12. After both sides are fixed, add clay and tamp until the model reaches the required density. Repeat the above steps until the filling is completed;

[0068] S4. Remove the rectangular steel pipe 12 and the baffle 15. After the core wall is cured, dig a groove on the surface of the core wall's central axis for installing the fiber Bragg grating sensor 6. Place the image acquisition and storage workstation 5 in the groove and fill it with test clay for compaction.

[0069] S5. Adjust the positions of the rectangular steel tube 12 and the third T-shaped steel 14 to ensure that the angle of the rectangular steel tube 12 meets the slope ratio required by the earth-rock dam model 19. Repeat step S3 to replace the clay material with rockfill material. During the filling process, bury the acceleration sensor 7 at the preset position. After the filling is completed, remove the rectangular steel tube 12, the third T-shaped steel 14, and the baffle 15.

[0070] S6. Place a high-definition digital SLR camera 4 in the middle of one side of the acrylic plate of the model box 1. Place the tripod on the vibration-isolating rubber laminate. Place a high-speed camera 18 above the model box 1. Connect all equipment and prepare to start the test.

[0071] S7. Simulating an earthquake state, the earth-rock dam model 19 begins to deform under the action of the earthquake load. During this process, the fiber grating sensor 6 records the strain data of the core wall, the fiber optic interrogator 2 analyzes the strain data transmitted by the fiber grating sensor 6 through the optical fiber, the high-definition digital SLR camera 4 continuously captures the position changes of any point on the observation surface at any time, the acceleration acquisition board 8 analyzes the acceleration data collected by the acceleration sensor 7 within the earth-rock dam model 19 during the test, and simultaneously, the high-speed camera 18 records the flow characteristics of the downstream rockfill material;

[0072] S8, the picture acquisition and storage workstation 5 transmits the collected photos to the computer 3, and processes the photos taken by the high-definition digital SLR camera 4 using PIV technology to obtain the displacement field of the earth-rock dam slope within the entire observation surface. The processed photos are post-processed to obtain a rich picture of the complete process from slope deformation to failure;

[0073] S9. Store the test data through the computer 3, and dismantle and clean the equipment.

[0074] The 20-panel earth-rock dam model is based on a dam with a height of 1.4m, a slope ratio of 1:1.4 for both upstream and downstream sides, a dam crest width of 8cm, and a panel thickness of 6-8mm. Figure 1 , the test steps are as follows:

[0075] S1. Fix the model box 1 and the shaking table together with bolts to ensure that the seismic waves output by the shaking table can be effectively transmitted to the earth-rock dam;

[0076] S2. Use bolts to fix the first T-shaped steel 11 and the mold frame 13 to the inner wall of the mold box 1 respectively. According to the slope ratio of the earth-rock dam slope required by the test, use bolts to connect the third T-shaped steel 14 and the first T-shaped steel 11. Use bolts to connect the two ends of the rectangular steel tube 12 to the strip-shaped hollow hole at the bottom of the mold frame 13 and the strip-shaped hollow hole inside the third T-shaped steel 14 respectively.

[0077] S3. Based on the height of the core wall layered and compacted, place the required number of baffles 15 above the two rectangular steel tubes 12 through the structure 102 at the top of the rectangular steel tubes 12. Once both sides are firmly fixed, add clay and compact until the model reaches the required density. Repeat the above steps until the filling is complete. Remove the rectangular steel tubes 12, the third T-shaped steel 14, and the baffles 15.

[0078] S4. Make the panel 20 and reserve a channel at the reserved position for burying the fiber Bragg grating sensor 6. After the curing is completed, bury the fiber Bragg grating sensor 6 and finally fix the sensor by grouting.

[0079] S5. Place a high-definition digital SLR camera 4 in the middle of one side of the acrylic plate of the model box 1. Place the tripod on the vibration-isolating rubber laminate. Place a high-speed camera 18 above the model box 1. Connect all equipment and prepare to start the test.

[0080] S6. Simulating an earthquake, the earth-rock dam model 19 begins to deform under the action of the earthquake load. During this process, the fiber grating sensor 6 records the strain data of the core wall, the fiber optic interrogator 2 analyzes the strain data transmitted by the fiber grating sensor 6 through the optical fiber, the high-definition digital SLR camera 4 continuously captures the position changes of any point on the observation surface at any time, the acceleration acquisition board 8 analyzes the acceleration data collected by the acceleration sensor 7 within the earth-rock dam model 19 during the test, and simultaneously, the high-speed camera 18 records the flow characteristics of the downstream rockfill material;

[0081] S7, the picture acquisition and storage workstation 5 transmits the collected photos to the computer 3, and processes the photos taken by the high-definition digital SLR camera 4 using PIV technology to obtain the displacement field of the earth-rock dam slope within the entire observation surface. The processed photos are post-processed to obtain a rich picture of the complete process of slope deformation until failure;

[0082] S8. Store the test data through the computer 3, and dismantle and clean the equipment.

[0083] Finally, it should be noted that the above embodiments are merely examples for the purpose of illustrating the present invention and are not intended to limit the embodiments. Those skilled in the art will readily appreciate that other variations or modifications based on the above description are possible. It is not necessary and impossible to provide an exhaustive list of all embodiments. However, obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A multifunctional device for earth-rock dam shaking table model test, characterized in that: include: The model box (1) has a bottom plate (9) provided at the bottom; Earth-rockfill dam model filling mold; Data acquisition system; The earth-rock dam model filling mold is sleeved inside the model box (1) from the top to the bottom, and the earth-rock dam model filling mold includes a mold frame (13), and third T-shaped steels (14) are provided at the two long sides of the inner side of the top of the mold frame (13), and first T-shaped steels (11) are provided at both ends of the two third T-shaped steels (14), and two baffles (15) are provided on the inner side of the bottom of the mold frame (13), and the two baffles (15) are symmetrically arranged on the left and right, and are trapezoidal in shape when matched with the top and bottom horizontal planes, and rectangular steel pipes (12) are provided at the two long sides of the top surface of the baffle (15); The data acquisition system comprises a high-definition digital single-lens reflex camera (4) and a high-speed camera (18); the high-definition digital single-lens reflex camera (4) and the high-speed camera (18) are connected to an image acquisition and storage workstation (5) by wireless signal transmission; the image acquisition and storage workstation (5) is connected to a computer (3) by wireless signal transmission; the computer (3) is further connected to an optical fiber demodulator (2) and an acceleration sensor (7) via a data line (10); the optical fiber demodulator (2) is connected to a fiber grating sensor (6) via the data line (10); and the acceleration sensor (7) is connected to an acceleration acquisition board (8) via the data line (10).

2. A multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The top of the model box (1) is in an open state, the front of the model box (1) is made of a transparent acrylic plate material, and the remaining three sides are made of a steel plate material, and the bottom plate (9) is connected to the vibration table through high-strength bolts.

3. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The earth-rock dam model (19) is divided into a core-wall earth-rock dam or a panel (20) earth-rock dam. When the earth-rock dam model (19) is a core-wall earth-rock dam, the fiber optic Bragg grating sensor (6) is divided into two groups and vertically arranged on both sides of the core wall center axis. When the earth-rock dam model (19) is a panel earth-rock dam, the fiber optic Bragg grating sensor (6) is arranged at the center axis of the panel (20) surface, and during the water addition test, the fiber optic Bragg grating sensor (6) is located at the upper middle position of the panel (20) surface.

4. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The fiber Bragg grating sensor (6) is a strain sensor, which consists of a fiber Bragg grating and two clamping components. A plastic tube (16) is provided outside the fiber Bragg grating, and end supports (17) are provided at both ends of the plastic tube (16). The fiber Bragg grating passes through the interior of the two end supports (17).

5. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: A plurality of acceleration sensors (7) are provided and arranged in a grid pattern inside the earth-rock dam model (19).

6. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The first T-shaped steel (11) is connected to the inner wall of the mold box (1) through high-strength bolts. A strip-shaped hollow hole is opened inside one side of the first T-shaped steel (11), and a bolt passes through the inside of the long hollow hole to connect with the third T-shaped steel (14). The third T-shaped steel (14) is supported by the two first T-shaped steels (11) and guided to move up and down on the inner side of the mold frame (13).

7. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: Strip-shaped hollow holes are reserved inside the long side of the bottom of the mold frame (13) and inside the third T-shaped steel (14). Both ends of the two rectangular steel tubes (12) are respectively connected to the inside of the two strip-shaped hollow holes. The two rectangular steel tubes (12) are guided by the strip-shaped hollow holes on the mold frame (13) and the third T-shaped steel (14) to move closer to or farther away from each other.

8. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The baffle (15) is a rigid plate and is connected to the rectangular steel pipe (12) through a mortise and tenon structure.

9. The multifunctional device for earth-rock dam shaking table model testing according to claim 1, characterized in that: The rectangular steel pipe (12) comprises a guide groove (121), a steel pipe strip (123) is provided inside the guide groove (121), and an opening (122) is provided at one corner of the guide groove (121).

10. A test method for a shaking table model test of an earth-rock dam, which is implemented based on the multifunctional device for a shaking table model test of an earth-rock dam according to any one of claims 1 to 9, characterized in that: include: S1, fixing the model box (1) and the vibration table together by bolts; S2. Use bolts to fix the first T-shaped steel (11) and the mold frame (13) to the inner wall of the model box (1), and use bolts to connect the third T-shaped steel (14) and the first T-shaped steel (11) according to the slope ratio of the earth-rock dam slope required by the test, and use bolts to connect the two ends of the rectangular steel tube (12) to the strip-shaped hollow hole at the bottom of the mold frame (13) and the strip-shaped hollow hole inside the third T-shaped steel (14); S3. According to the height of the core wall layered compaction, place the required number of baffles (15) from above the two rectangular steel tubes (12) through the structure (102) on the top of the rectangular steel tube (12). After both sides are fixed, add clay and compact until the model reaches the required density. Repeat the above steps until the filling is completed; S4, remove the rectangular steel pipe (12) and the baffle (15), wait for the core wall to be cured, dig a groove for installing the fiber optic Bragg grating sensor (6) on the surface of the core wall's central axis, place the image acquisition and storage workstation (5) in the groove, and fill and compact it with experimental clay; S5, adjusting the positions of the rectangular steel tube (12) and the third T-shaped steel (14), ensuring that the angle of the rectangular steel tube (12) meets the slope ratio required by the earth-rock dam model (19), repeating step S3, replacing the clay material with rockfill material, and burying the acceleration sensor (7) at a preset position during the filling process, and removing the rectangular steel tube (12), the third T-shaped steel (14) and the baffle (15) after the filling is completed; S6. Place a high-definition digital SLR camera (4) in the middle of one side of the acrylic plate of the model box (1), place the tripod on the vibration-isolating rubber laminate, place a high-speed camera (18) above the model box (1), connect all the equipment, and prepare to start the test; S7, simulating an earthquake state, the earth-rock dam model (19) begins to deform under the action of the earthquake load. During this process, the fiber optic Bragg grating sensor (6) records the strain data of the core wall, the fiber optic demodulator (2) analyzes the strain data transmitted by the fiber optic Bragg grating sensor (6) through the optical fiber, the high-definition digital single-lens reflex camera (4) continuously captures the position change of any point on the observation surface at any time, the acceleration acquisition board (8) analyzes the acceleration data collected by the acceleration sensor (7) in the earth-rock dam model (19) during the test, and at the same time, the flow characteristics of the downstream rockfill material are recorded by the high-speed camera (18); S8, the picture acquisition and storage workstation (5) transmits the collected photos to the computer (3), and processes the photos taken by the high-definition digital SLR camera (4) through the PIV technology to obtain the displacement field of the earth-rock dam slope in the entire observation surface. The processed photos are post-processed to obtain a rich complete process of slope deformation until failure; S9. Store the test data through the computer (3), and dismantle and clean the equipment.

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