Three-sample dynamic double-shear test equipment and test method

Abstract

The invention provides three-sample dynamic double-shear test equipment and a three-sample dynamic double-shear test method, and relates to geotechnical engineering. The three-sample clamp system comprises two horizontal bearing tables, and a downwards sunken avoiding groove is formed between the two horizontal bearing tables; two lateral dynamic constraint systems; a vertical dynamic loading system; the measurement and control system is used for controlling the two horizontal actuators to clamp the middle sample between the two single-side samples and controlling the vertical actuators to apply vertical loads to the two single-side samples and the middle sample, so that the middle sample moves downwards relative to the two single-side samples; therefore, two parallel shearing surfaces are formed on the contact side surfaces of the two single-side samples and the middle sample. The method has the beneficial effects that the possibility of deflection of the sample is eliminated from the mechanical principle, the extreme uniformity of stress distribution on the shear surface is ensured, and the non-representative local damage of the joint surface is effectively avoided, so that the shear test precision is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of geotechnical engineering technology, and in particular to a three-sample dynamic double shear test equipment and test method. Background Technology

[0002] In seismic analysis, slope stability assessment, and research on the mechanical behavior of composite materials in geotechnical engineering, obtaining accurate shear mechanical parameters of materials under dynamic loads is crucial. Traditional dynamic shear testing equipment, such as cyclic single shear testers and resonant column testers, generally suffers from a critical drawback: during the shearing process, the specimen is prone to uncontrollable deflection or rotation due to insufficient boundary constraints. This rotation leads to severely uneven stress distribution within the specimen, resulting in large dispersion of test data and difficulty in guaranteeing accuracy and repeatability, directly affecting the accuracy and safety of engineering designs.

[0003] While some existing technologies attempt to increase lateral constraints, these are mostly passive or rigid constraints, making it difficult to restrict rotation without affecting the free shear deformation of the specimen. Furthermore, traditional equipment can only acquire data from one shear plane per test, resulting in low efficiency and the inability to internally verify the reliability of a single test.

[0004] Therefore, there is an urgent need in this field for an efficient and high-precision dynamic shear testing device that can fundamentally prevent sample rotation and provide a built-in data verification mechanism. Summary of the Invention

[0005] In view of this, the present invention provides a three-sample dynamic double shear test equipment and test method to solve the problem that the accuracy and repeatability are difficult to guarantee due to the deflection of the specimen during the dynamic shear test of materials.

[0006] An embodiment of the present invention provides a three-sample dynamic double-shear testing device, comprising: Rigid load-bearing frame; The three-sample clamping system includes two horizontal support platforms, which are fixedly and spaced apart on the rigid support frame, so that a downward recessed clearance groove is formed between the two horizontal support platforms. The two horizontal support platforms are used to support two single-sided samples, and the middle sample clamped by the two single-sided samples is placed above the clearance groove. Two lateral dynamic constraint systems are respectively disposed on both sides of the clearance groove. The lateral dynamic constraint system includes a horizontal actuator. The two horizontal actuators are respectively disposed on the outside of the two horizontal bearing platforms to clamp the two single-sided specimens by moving towards each other. A vertical dynamic loading system includes a vertical actuator, which is disposed above the two horizontal support platforms and the clearance groove; The system includes a measurement and control system that connects the two horizontal actuators and the vertical actuator. The system controls the two horizontal actuators to clamp the intermediate sample between the two single-sided samples and controls the vertical actuator to apply a vertical load to the two single-sided samples and the intermediate sample, so that the intermediate sample moves downward relative to the two single-sided samples, thereby forming two parallel shear surfaces on the sides where the two single-sided samples and the intermediate sample are in contact.

[0007] Furthermore, the three-sample fixture system also includes two lateral constraint plates, each of which is slidably disposed on a horizontal support platform, such that each horizontal actuator can drive one of the lateral constraint plates to move horizontally toward the other lateral constraint plate.

[0008] Furthermore, the three-sample fixture system also includes two constraint frames, each of which is fixedly connected to a horizontal support platform and fits over the lateral constraint plate above the horizontal support platform, so that the lateral constraint plate can only move horizontally toward the other lateral constraint plate.

[0009] Furthermore, the vertical dynamic loading system includes a loading cap, the upper end of which is connected to the vertical actuator, and the lower end is provided with two parallel upper limit spacers, the two upper limit spacers being respectively aligned with the sides of the two single-sided samples that contact the middle sample.

[0010] Furthermore, each of the horizontal support platforms is provided with a lower limiting spacer on the side near the clearance groove, the lower limiting spacer being used to separate the single-sided sample and the intermediate sample.

[0011] Furthermore, the contact surfaces of the horizontal bearing platform and the single-sided specimen, the contact surfaces of the lateral constraint plate and the single-sided specimen, and the contact surfaces of the loading cap and the single-sided specimen are all provided with friction contact layers.

[0012] Furthermore, the static friction coefficient of the friction contact layer is not greater than 0.15.

[0013] Furthermore, the measurement and control system also includes a vertical displacement sensor and a vertical force sensor installed on the vertical actuator, and a lateral force sensor installed on the horizontal actuator.

[0014] Furthermore, embodiments of the present invention also provide a dynamic shear performance testing method, using the aforementioned three-sample dynamic double shear testing equipment, and including the following steps: S1. Install two single-sided specimens on the two horizontal support platforms respectively, and place the middle specimen between the two single-sided specimens. S2. The two lateral dynamic constraint systems move toward each other through the two horizontal actuators to clamp the two single-sided specimens with a preset force, so that the middle specimen is clamped by the two single-sided specimens. S3. The vertical dynamic loading system applies vertical loads to the two single-sided specimens and the intermediate specimen through a vertical actuator, causing relative shear between the intermediate specimen and the two single-sided specimens. S4. Collect the total load, vertical displacement, and lateral constraint force data of the two horizontal actuators of the vertical actuator; S5. Based on the collected data, calculate the shear stress and shear strain on the two shear surfaces of the two single-sided specimens respectively, and calculate the dynamic shear modulus, damping ratio and shear strength parameters of the material accordingly.

[0015] Furthermore, it also includes S6, which assesses the consistency of the data for the two shear surfaces by comparing the two stress-strain curves of the two shear surfaces.

[0016] The beneficial effects of the technical solutions provided by the embodiments of the present invention are as follows: 1. This invention provides a three-sample dynamic double-shear testing equipment and method. The three-sample clamping system clamps the middle sample and the two single-sided samples on both sides as a whole. Any torque attempting to rotate the middle sample and the two single-sided samples will be resisted by the strong, synchronous lateral constraint force from the horizontal actuators on both sides. This symmetrical rigid constraint strictly limits the movement of the middle sample to vertical translation, completely eliminating deflection. From a mechanical principle perspective, this eliminates the possibility of sample deflection, ensuring extremely uniform stress distribution on the shear surface and effectively avoiding non-representative local damage to the joint surface. This significantly improves the accuracy of shear testing, especially the shear strength testing of jointed rock masses. 2. The present invention provides a three-sample dynamic double shear test equipment and test method that simultaneously obtains the shear surface data of two single-sided samples in one test. By comparing the consistency of the two stress-strain curves, the reliability of the test process and the uniformity of the samples can be effectively evaluated, which is something that traditional equipment cannot achieve.

[0017] 3. The present invention provides a three-sample dynamic double shear test equipment and test method, which can obtain the shear surface data of two single-sided samples in one test, which is equivalent to completing two shear tests in one test, thus improving the test efficiency. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a three-sample dynamic double-shear testing device according to the present invention; Figure 2 This is a partial schematic diagram of a three-sample dynamic double-shear testing device according to the present invention; Figure 3This is a hardware connection block diagram of the measurement and control system; Figure 4 This is a comparison diagram of the normal stress deflection between the three-sample dynamic double shear test equipment of this invention and the traditional dynamic shear test equipment.

[0019] In the figure: 1. Rigid bearing frame; 2. Three-sample fixture system; 3. Lateral dynamic constraint system; 4. Vertical dynamic loading system; 5. Measurement and control system; 6. Frame; 7. Horizontal bearing platform; 8. Clearance groove; 9. Horizontal actuator; 10. Vertical actuator; 11. Lateral constraint plate; 12. Loading cap; 13. Constraint frame; 14. Single-sided sample; 15. Intermediate sample. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described below with reference to the accompanying drawings. The following description presents a preferred embodiment of the various possible embodiments of the present invention, intended to provide a basic understanding of the invention, but not intended to identify key or decisive elements of the invention or to limit the scope of protection sought.

[0021] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0022] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures. Also, it should be understood that, for ease of description, the dimensions of the various parts shown in the figures are not drawn to actual scale.

[0024] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Please refer to Figure 1 The present invention provides a three-sample dynamic double shear test equipment, including a rigid bearing frame 1, a three-sample clamping system 2, two lateral dynamic constraint systems 3, a vertical dynamic loading system 4, and a measurement and control system 5.

[0026] The rigid load-bearing frame 1 serves as the load-bearing foundation and is generally fixedly installed within the frame 6. In this embodiment, the rigid load-bearing frame 1 is welded from high-quality Q345B steel plate, and the frame's natural frequency is designed to be much higher than the test frequency range, ensuring that its own deformation is negligible during dynamic loading and providing an absolutely stable foundation for testing.

[0027] Combination Figure 2 As shown, the three-sample clamping system 2 includes two horizontal support platforms 7, which are fixedly and spaced apart on the rigid support frame 1, forming a downwardly recessed clearance groove 8 between the two horizontal support platforms 7. The two horizontal support platforms 7 are used to support two single-sided samples 14, and the middle sample 15 clamped by the two single-sided samples 14 is placed above the clearance groove 8. Specifically, the rigid support frame 1 has a rectangular groove in the middle, and the two horizontal support platforms 7 are symmetrically fixed in the middle of the groove, with the clearance groove 8 formed between the two horizontal support platforms 7 being a rectangular groove.

[0028] Two lateral dynamic restraint systems 3 are respectively disposed on both sides of the clearance groove 8. Each lateral dynamic restraint system 3 includes a horizontal actuator 9. The two horizontal actuators 9 are respectively disposed on the outer sides of the two horizontal bearing platforms 7 and symmetrically mounted on the frame 6. The two horizontal actuators 9 can move towards each other to simultaneously push the two single-sided specimens 14 to clamp the intermediate specimen 15.

[0029] The horizontal actuator 9 can be flexibly selected according to the performance parameters required for actual testing. In this embodiment, the horizontal actuator 9 is preferably a servo hydraulic actuator with a maximum output of 80kN, a stroke of ±30mm, and a frequency response of ≥10Hz. Each actuator integrates a high-precision force sensor (accuracy ±0.1% FS) and an LVDT displacement sensor (accuracy ±0.1% FS).

[0030] In some embodiments, the three-sample fixture system 2 further includes two lateral constraint plates 11, each of which is slidably disposed on a horizontal support platform 7, such that each horizontal actuator 9 can drive one lateral constraint plate 11 to move horizontally toward the other lateral constraint plate 11. The lateral constraint plates 11 are made of a rigid material, such as, by way of example, high-strength alloy steel (e.g., 40Cr), with a hard chrome plated surface for wear resistance and rust prevention.

[0031] Furthermore, in order to ensure that the lateral constraint plate 11 moves in an accurate direction to press the single-sided sample 14 against the other side, the three-sample fixture system 2 also includes two constraint frames 13. Each constraint frame 13 is fixedly connected to a horizontal support platform 7 and fits over the lateral constraint plate 11 above the horizontal support platform 7, so that the lateral constraint plate 11 can only move horizontally toward the other lateral constraint plate 11.

[0032] The vertical dynamic loading system 4 includes a vertical actuator 10, which is positioned above the two horizontal support platforms 7 and the clearance groove 8. The vertical actuator 10 can be flexibly selected according to the performance parameters required for actual testing. For example, in this embodiment, the vertical actuator 10 is selected to be servo hydraulically actuated, with a maximum output of 150kN, a stroke of ±50mm, and a dynamic loading frequency range of 0.01-10Hz.

[0033] like Figure 3 As shown, the measurement and control system 5 connects the two horizontal actuators 9 and the vertical actuator 10. It controls the two horizontal actuators 9 to clamp the intermediate sample 15 between the two single-sided samples 14, and controls the vertical actuator 10 to apply a vertical load to the two single-sided samples 14 and the intermediate sample 15, causing the intermediate sample 15 to move downwards relative to the two single-sided samples 14, thereby forming two parallel shear surfaces on the sides where the two single-sided samples 14 contact the intermediate sample 15. The measurement and control system 5 can independently set the lateral constraint force (constant or time-history curve) applied by the horizontal actuators 9, and the vertical loading waveform (sine wave, square wave, triangle wave, custom), frequency, amplitude, etc., of the load output by the vertical actuator 10.

[0034] To precisely define the clamping positions of the two single-sided specimens 14 and the intermediate specimen 15, the vertical dynamic loading system 4 includes a loading cap 12. The upper end of the loading cap 12 is connected to the vertical actuator 10, and the lower end is provided with two parallel upper limit spacers. The output end of the vertical actuator 10 is connected to the loading cap 12 via a ball joint to compensate for possible minor alignment errors. The two upper limit spacers are respectively aligned with the sides of the two single-sided specimens 14 and the intermediate specimen 15 that are in contact. The two upper limit spacers on the bottom surface of the loading cap 12 align the tops of the sides of the two single-sided specimens 14 and the intermediate specimen 15 that are in contact. In addition, a lower limit spacer can be provided on the side of each horizontal support platform 7 near the clearance groove 8. The lower limit spacer is used to separate the single-sided specimens 14 and the intermediate specimen 15. The two lower limit spacers are aligned with the bottoms of the sides of the two single-sided specimens 14 and the intermediate specimen 15 that are in contact.

[0035] The contact surfaces of the horizontal bearing platform 7 and the single-sided specimen 14, the lateral constraint plate 11 and the single-sided specimen 14, and the loading cap 12 and the single-sided specimen 14 are all provided with friction contact layers. The friction contact layers are embedded in the contact surfaces and have a low coefficient of friction to minimize the interference of lateral friction on the shear test. The static coefficient of friction of the friction contact layer is generally no greater than 0.15, and more preferably no greater than 0.10. For example, in this embodiment, the friction contact layer is selected from 2mm thick polytetrafluoroethylene (PTFE) sheets.

[0036] In some embodiments, to simultaneously acquire mechanical response data on two shear planes, the measurement and control system 5 further includes a vertical displacement sensor and a vertical force sensor mounted on the vertical actuator 10, and a lateral force sensor mounted on the horizontal actuator 9. The vertical displacement sensor can acquire vertical displacement, the vertical force sensor can acquire the total vertical load, and the lateral force sensor can acquire two lateral constraint force data.

[0037] Furthermore, embodiments of the present invention also provide a dynamic shear performance testing method, using the aforementioned three-sample dynamic double shear testing equipment, and including the following steps: S1. Two single-sided specimens 14 are respectively installed on the two horizontal support platforms 7, and the intermediate specimen 15 is placed between the two single-sided specimens 14. The intermediate specimen 15 and the two single-sided specimens 14 are both standard specimens in the shape of cuboids.

[0038] S2. The two lateral dynamic constraint systems 3 move toward each other through the two horizontal actuators 9 to clamp the two single-sided specimens 14 with a preset force, so that the intermediate specimen 15 is clamped by the two single-sided specimens 14.

[0039] S3. The vertical dynamic loading system 4 applies a vertical load to the two single-sided specimens 14 and the intermediate specimen 15 through the vertical actuator 10, causing relative shear between the intermediate specimen 15 and the two single-sided specimens 14. Figure 2 As shown, the red "X" indicates the contact surface where the relative motion occurs between the middle sample 15 and the two side samples. These two surfaces are the double shear surfaces being measured.

[0040] During shearing, any torque attempting to rotate the intermediate specimen 15 and the two side specimens will be resisted by the strong, synchronized lateral constraint forces provided by the horizontal actuators 9 on both sides. This symmetrical rigid constraint strictly limits the movement of the intermediate specimen 15 and the two side specimens to vertical translation, completely eliminating deflection.

[0041] S4. Collect the total load, vertical displacement, and lateral constraint force data of the two horizontal actuators 9 of the vertical actuator 10; S5. Based on the collected data, calculate the shear stress (τ) and shear strain (γ) on the two shear surfaces of the two single-sided specimens 14, plot the stress-strain curves, and calculate the dynamic shear modulus, damping ratio and shear strength parameters of the material accordingly.

[0042] Furthermore, to effectively assess the reliability of the testing process and the uniformity of the samples, the dynamic shear performance testing method of this invention also includes S6: evaluating the consistency of the data from the two shear surfaces by comparing the two stress-strain curves of the two shear surfaces. The measurement and control system 5 described here can automatically calculate and display the average value, standard deviation, or coefficient of variation of the results from the two shear surfaces, intuitively reflecting the consistency of the test.

[0043] The present invention also verifies the fundamental improvements of the three-sample dynamic double-shear test equipment in this embodiment in suppressing sample rotation and ensuring test accuracy.

[0044] The comparative equipment is existing traditional dynamic shear testing equipment, specifically as follows: Figure 4 The model shown in the lower middle section.

[0045] Measurement method: A high-precision non-contact displacement measurement system (such as a video strain gauge or laser displacement meter) is installed on the specimens of both types of equipment to accurately measure the normal stress deflection (%) of the specimen in the vertical plane. This parameter is defined as the percentage of lateral displacement of the specimen's central axis due to rotation to the specimen height, and is a direct indicator of the degree of specimen rotation.

[0046] Testing process: Standard sand samples with identical geometric and physical properties were installed on two different devices.

[0047] The same constant normal stress is applied to the specimen.

[0048] The shear chambers are driven separately to produce a series of increasing shear displacements in the sample (e.g., 0.5 cm, 1.0 cm, 1.5 cm...).

[0049] At each fixed shear displacement, after the deformation stabilizes, record the corresponding normal stress deflection (%) value.

[0050] Results and Analysis: The core test results are shown in the attached instruction manual. Figure 4 As shown in the figure, the shear displacement is the implicit test condition, and the Y-axis clearly shows the corresponding normal stress deflection (%).

[0051] Curve Comparison Analysis: Test curves of traditional dynamic shear testing equipment (before improvement) (e.g., marked 0.5cm before improvement): as shown in the attached figure. Figure 4 As shown, the curve measured by the conventional equipment is at a higher position. This indicates that even with a small shear displacement (e.g., 0.5 cm), the specimen exhibits significant rotational deflection (a large percentage of normal stress deflection). Furthermore, as the shear displacement increases, the percentage of deflection rises sharply, reflecting increased instability and a rapid deterioration of the stress state.

[0052] The test curve of the three-sample dynamic double shear test equipment (after improvement) (as indicated by the 0.5cm mark after improvement): In stark contrast, the test curve of the three-sample dynamic double shear test equipment of this invention is located extremely low, almost touching the horizontal axis of the coordinate system. Throughout the entire shear displacement test range, the percentage of normal stress deflection remains at an extremely low level close to zero and does not change significantly with the increase of shear displacement.

[0053] This sufficiently demonstrates that the three-sample dynamic double-shear testing equipment provided by this invention, through its innovative "three-sample double-shear surface" design, constructs an inherently stable testing system capable of actively preventing sample rotation. It not only solves the long-standing accuracy problem in dynamic shear testing but also greatly improves the reliability of results through data self-verification, while simultaneously increasing testing efficiency, providing a groundbreaking tool for the refined study of the dynamic properties of soil and materials.

[0054] In this document, the directional terms such as front, back, top, and bottom are defined based on the location of the components in the accompanying drawings and their relative positions to each other, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that these are relative concepts and can vary depending on different methods of use and placement; the use of these directional terms should not limit the scope of protection claimed in this application.

[0055] Where there is no conflict, the embodiments and features described above can be combined with each other. The above descriptions are merely preferred embodiments of the present invention and are not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A triaxial dynamic simple shear test apparatus, characterized by, include: Rigid load-bearing frame; The three-sample clamping system includes two horizontal support platforms, which are fixedly and spaced apart on the rigid support frame, so that a downward recessed clearance groove is formed between the two horizontal support platforms. The two horizontal support platforms are used to support two single-sided samples, and the middle sample clamped by the two single-sided samples is placed above the clearance groove. Two lateral dynamic constraint systems are respectively disposed on both sides of the clearance groove. The lateral dynamic constraint system includes a horizontal actuator. The two horizontal actuators are respectively disposed on the outside of the two horizontal bearing platforms to clamp the two single-sided specimens by moving towards each other. A vertical dynamic loading system includes a vertical actuator, which is disposed above the two horizontal support platforms and the clearance groove; The system includes a measurement and control system that connects the two horizontal actuators and the vertical actuator. The system controls the two horizontal actuators to clamp the intermediate sample between the two single-sided samples and controls the vertical actuator to apply a vertical load to the two single-sided samples and the intermediate sample, so that the intermediate sample moves downward relative to the two single-sided samples, thereby forming two parallel shear surfaces on the sides where the two single-sided samples and the intermediate sample are in contact.

2. A triaxial dynamic simple shear test apparatus as claimed in claim 1, wherein: The three-sample fixture system also includes two lateral constraint plates, each of which is slidably disposed on a horizontal support platform, such that each horizontal actuator can drive one of the lateral constraint plates to move horizontally toward the other lateral constraint plate.

3. The three-sample dynamic double-shear testing equipment as described in claim 2, characterized in that: The three-sample fixture system also includes two constraint frames, each of which is fixedly connected to a horizontal support platform and fits over the lateral constraint plate above the horizontal support platform, so that the lateral constraint plate can only move horizontally toward the other lateral constraint plate.

4. The three-sample dynamic double-shear testing equipment as described in claim 2, characterized in that: The vertical dynamic loading system includes a loading cap, the upper end of which is connected to the vertical actuator, and the lower end is provided with two parallel upper limit spacers, which are respectively aligned with the sides of the two single-sided samples that are in contact with the middle sample.

5. The three-sample dynamic double-shear testing equipment as described in claim 4, characterized in that: Each of the horizontal support platforms is provided with a lower limit spacer on the side near the clearance groove, and the lower limit spacer is used to separate the single-sided sample and the intermediate sample.

6. The three-sample dynamic double-shear testing equipment as described in claim 5, characterized in that: The contact surfaces of the horizontal bearing platform and the single-sided specimen, the contact surfaces of the lateral constraint plate and the single-sided specimen, and the contact surfaces of the loading cap and the single-sided specimen are all provided with friction contact layers.

7. The three-sample dynamic double-shear testing equipment as described in claim 6, characterized in that: The static friction coefficient of the friction contact layer is no greater than 0.

15.

8. The three-sample dynamic double-shear testing equipment as described in claim 1, characterized in that: The measurement and control system also includes a vertical displacement sensor and a vertical force sensor installed on the vertical actuator, and a lateral force sensor installed on the horizontal actuator.

9. A method for testing dynamic shear properties, characterized in that: Using a three-sample dynamic double-shear test apparatus as described in any one of claims 1-8, and comprising the following steps: S1. Install two single-sided specimens on the two horizontal support platforms respectively, and place the middle specimen between the two single-sided specimens. S2. The two lateral dynamic constraint systems move toward each other through the two horizontal actuators to clamp the two single-sided specimens with a preset force, so that the middle specimen is clamped by the two single-sided specimens. S3. The vertical dynamic loading system applies vertical loads to the two single-sided specimens and the intermediate specimen through a vertical actuator, causing relative shear between the intermediate specimen and the two single-sided specimens. S4. Collect the total load, vertical displacement, and lateral constraint force data of the two horizontal actuators of the vertical actuator; S5. Based on the collected data, calculate the shear stress and shear strain on the two shear surfaces of the two single-sided specimens respectively, and calculate the dynamic shear modulus, damping ratio and shear strength parameters of the material accordingly.

10. The dynamic shear performance testing method as described in claim 9, characterized in that: It also includes S6, which assesses the consistency of data for two shear surfaces by comparing the two stress-strain curves of the two shear surfaces.

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