In-situ compression and shear test device and test method for slope rock and soil

Abstract

This invention discloses an in-situ compression-shear testing device and method for slope soil and rock, belonging to the field of in-situ shear testing technology for soil and rock. The device includes a fixed base, a multi-link structure, a pressure application component, sensors, an analog-to-digital converter, and an industrial computer. The testing method includes soil sample preparation, device installation, data acquisition and pressure application, shear failure recording, data analysis, and parameter calculation. The shear strength parameters of the soil are determined through in-situ testing. During the test, a laser scanner is used to create a three-dimensional model of the shear surface, accurately calculating the shear surface area and inclination angle. The accuracy of the results is verified by combining machine learning and finite element analysis. This invention avoids sampling disturbance, improves test accuracy, enables multi-angle shear characteristic research, enhances reliability through intelligent data acquisition and analysis, reduces test costs, and increases efficiency. It provides a scientific basis for slope stability analysis and support design, is applicable to various complex geological conditions, and has significant engineering application value.

Description

Technical Field

[0001] This invention relates to the field of in-situ shear testing technology for soil and rock masses, and particularly to an in-situ compression-shear testing device and method for slope soil and rock masses. Background Technology

[0002] Slope stability is a crucial research topic in geotechnical engineering, and the accuracy of its evaluation directly impacts the safety and economic efficiency of slope engineering projects. In slope stability analysis, the shear strength parameters of the slope's soil and rock mass play a decisive role in the analysis and design of the support structure. Current national standards provide corresponding recommendations for selecting testing methods for different types of slope soil and rock masses:

[0003] 1. Saturated soft soil: Direct shear test, triaxial unconsolidated undrained test, or vane shear test are recommended. 2. Clay and silty clay: Direct shear test, consolidated shear test, or triaxial consolidated undrained shear test are recommended. 3. Silt, sand and gravelly soil: Effective stress strength index is recommended. 4. Rock mass structural plane: Shear strength is usually determined by laboratory tests combined with experience from similar projects.

[0004] However, the aforementioned traditional testing methods have the following prominent problems in practical applications, affecting the accuracy and reliability of the test results:

[0005] 1. Disturbance of soil and rock samples: Soil and rock samples are easily disturbed during drilling, sampling and transportation to the laboratory, especially highly sensitive soils such as saturated soft soil. They are easily damaged by external forces, which can lead to deviations in test data and make it difficult to reflect the true mechanical properties.

[0006] 2. Difficulty in obtaining undisturbed samples: For coarse-grained soils such as silt, sand, and gravelly soil, it is difficult to obtain complete undisturbed samples during drilling. Gravelly soil, in particular, contains large stones, making it impossible to prepare regular samples, further limiting the applicability of laboratory tests.

[0007] 3. Limitations of sampling rock mass structural surfaces: During drilling, rock mass structural surfaces are easily disturbed or damaged. Typically, drilling can only obtain well-cemented rock masses (such as calcareous, siliceous, and ferruginous cemented surfaces), while it is difficult to obtain complete samples from muddy cemented structural surfaces that are detrimental to slope stability. This results in test results that cannot fully reflect the true condition of the slope.

[0008] 4. Limitations of the applicability of the field vane shear test: While the field vane shear test is suitable for soft clay, it is not applicable to stiff plastic clay or soils containing gravel and debris. Conducting the test under these conditions may damage the vane head, thus affecting the accuracy of the test results.

[0009] 5. Shear surface problem in in-situ large shear test: The shear surface in the in-situ large shear test is limited to the space between the upper and lower boxes. This artificially set shear surface is often not the actual weakest surface of the soil. Therefore, the obtained shear strength index is usually too large and cannot truly reflect the shear performance of the slope soil and rock. Summary of the Invention

[0010] To address the aforementioned problems, this invention provides an in-situ compression-shear test device and method for slope rock and soil, aiming to solve the problems of disturbance, sampling difficulties, and test data deviation in traditional test methods.

[0011] The technical solution adopted in this invention is as follows:

[0012] An in-situ compression-shear test device for slope soil and rock includes a fixed base horizontally fixed to the foundation soil by anchor bolts. A pressure-applying component is installed on the fixed base via a multi-link structure, extending to the test soil sample side to apply pressure to the sample. The device also includes a pressure sensor, an inclination sensor, a laser displacement rangefinder, a laser scanner, an analog-to-digital converter (ADC), and an industrial computer. The pressure sensor and inclination sensor are mounted on the pressure-applying component, while the laser scanner and ADC are independently mounted near the test soil sample. The pressure sensor, inclination sensor, laser displacement rangefinder, and ADC are wired to each other, and the industrial computer is wired to the ADC, laser scanner, and pressure-applying component.

[0013] Furthermore, the fixed base is a rectangular plate structure with a spirit level embedded in the center of its top surface and mounting holes at its four corners for anchor bolts to pass through.

[0014] Furthermore, the multi-link structure includes three first support rods arranged in a triangle. One end of each first support rod is mounted on a fixed base via a hinged seat. The other ends of the three first support rods converge at a point and are hinged to one end of a third support rod. A pressure-applying component is installed at the other end of the third support rod. The multi-link structure also includes a second support rod. One end of the second support rod is hinged to the middle section of the third support rod, and the hinge point position can be changed. Its other end is hinged to one of the three first support rods.

[0015] Furthermore, the pressure application assembly includes a hydraulic jack installed at the other end of the third support rod, and a hydraulic servo system connected to the hydraulic jack pipeline; a pressure plate is installed on the telescopic rod of the hydraulic jack; the hydraulic servo system is wired to an industrial computer.

[0016] A method for in-situ compression-shear testing of slope rock and soil, the method being based on the aforementioned in-situ compression-shear testing apparatus for slope rock and soil, is characterized by comprising the following steps:

[0017] S1 soil sample preparation: Excavate a platform on the slope and prepare 3 sets of test soil samples in the shape of a truncated pyramid; trim the pressure surface on the slope side of each set of test soil samples, with the inclination angle of the pressure surface of each set of soil samples differing by 10° to 15° to ensure that it can fit flat and adhere to the pressure plate.

[0018] S2 device installation: Install the fixed base on the foundation soil and adjust the fixed base to be level; install the multi-link structure and pressure application component based on the fixed base, and adjust the angle of the pressure application component through the multi-link structure; turn on the tilt sensor, laser displacement rangefinder and laser scanner to ensure normal operation of the equipment.

[0019] S3 Data Acquisition and Pressurization: The hydraulic servo system is activated by an industrial computer to apply pressure at a constant speed, and pressure data, test soil sample displacement data and pressure component tilt angle data are recorded in real time.

[0020] S4 Shear Failure and Recording: Apply pressure continuously until the test soil sample fails in shear, record the maximum pressure data and the displacement data of the test soil sample at failure; use a laser scanner to measure the geometric parameters of the shear surface, and calculate the shear surface area and inclination angle;

[0021] S5 Data Analysis and Parameter Calculation: The compressive stress and shear stress on the shear surface of the test soil sample are calculated by an industrial computer, the σ-τ line is fitted, and the internal friction angle and cohesion are extracted.

[0022] S6 Test Termination and Dismantling: After the data analysis system issues a test termination message, stop the test; dismantle the test equipment and clean up the site.

[0023] Furthermore, during the S3 data acquisition and pressurization process, the pressure sensor measures the pressure data F applied by the hydraulic jack, the tilt sensor measures the tilt data θ1 of the pressure plate, and the laser displacement rangefinder measures the displacement data S of the test soil during pressurization. The pressure data F, tilt data θ1, and displacement data S of the test soil are converted into digital signals by an analog-to-digital converter and transmitted to the industrial computer.

[0024] Furthermore, S4 shearing destruction and recording include the following steps:

[0025] Step 4.1: Continue to apply pressure until the test soil sample fails under shear. Record the pressure and displacement changes during the pressure application process until the test soil sample fails under shear. Generate a curve showing the change in pressure on the pressure plate versus the displacement of the test soil during the pressure application process. Record the maximum pressure F based on the curve. max and displacement S at failure max ;

[0026] Step 4.2: After the soil sample fails under shear, remove the pressure plate, remove the soil above the shear surface, use a laser scanner to create a three-dimensional model of the shear surface, measure the side lengths a, b, c, d and the diagonal length L of the shear surface, and calculate the area A of the shear surface.

[0027] The formula for calculating the cross-sectional area A is as follows:

[0028] A=[P1×(P1-a)×(P1-b)×(P1-L)] 0.5 +[P2×(P2-c)×(P2-d)×(P2-L)] 0.5

[0029] In the formula, P1 and P2 are intermediate variables, P1 = (a + b + L) / 2, P2 = (c + d + L) / 2;

[0030] Step 4.3: Attach the pressure plate to the shear surface, measure the inclination angle θ2 of the shear surface normal, calculate the inclination angle α of the shear surface, and the pressure angle β between the shear surface and the pressure plate;

[0031] The formula for calculating the shear plane inclination angle α is as follows:

[0032] α = 90° - θ²

[0033] The formula for calculating the angle β between the shear plane and the pressure of the pressure plate is as follows:

[0034] β = θ1 - α.

[0035] Furthermore, S5 data analysis and parameter calculation include the following steps:

[0036] Step 5.1, calculate the compressive stress σ and shear stress τ on the shear plane:

[0037]

[0038] In the formula, σ represents the normal stress on the shear plane; F n The maximum pressure F applied to the pressure plate max The normal component along the shear plane; A is the area of ​​the shear plane; β is the angle between the shear plane and the pressure plate; F max Maximum pressure during pressurization; τ represents the tangential stress on the shear plane; F t The maximum pressure F applied to the pressure plate max Tangential components decomposed along the shear plane;

[0039] Step 5.2: Conduct compression-shear tests on soil samples with different inclination angles to obtain multiple sets of σ. i τ i data;

[0040] Step 5.3: Use a multi-parameter fitting model to fit the σ-τ line and calculate the internal friction angle φ and cohesion c of the soil.

[0041] The calculation formula is: τ=c+σ·tanφ;

[0042] In the formula, φ is the angle between the abscissa of the straight line and the fitted σ-τ line, i.e., the internal friction angle; c is the intersection of the ordinate of the straight line and the fitted σ-τ line, i.e., the cohesion.

[0043] Furthermore, the in-situ compression-shear test method for this slope soil and rock mass also includes:

[0044] S7 Machine Learning and Numerical Simulation: Historical test data, including hydraulic jack pressure data F, soil displacement data S, pressure plate inclination data θ1, measured shear surface normal inclination angle θ2, shear surface area A, compressive stress σ on the shear surface, and shear stress τ on the shear surface, are imported into a machine learning model to train an algorithm to predict soil shear failure modes and mechanical properties. Then, combined with finite element analysis, the accuracy of the test results is verified, and slope stability is evaluated.

[0045] The beneficial effects of this invention are:

[0046] 1. Intelligent and automated: Real-time acquisition, transmission and analysis of test data are achieved through intelligent sensor networks and automated control systems, reducing human error.

[0047] 2. High-precision measurement: Laser scanning technology is used to create a three-dimensional model of the shear surface and accurately calculate the area of ​​the shear surface.

[0048] 3. Multi-source data fusion: Combining data such as pressure, displacement, and tilt angle, to comprehensively analyze the shear failure process of soil.

[0049] 4. Improved test accuracy and reliability: The on-site shear test is performed by shearing along the weakest surface of the specimen, avoiding errors caused by shearing along a limited shear plane.

[0050] 5. High adaptability: The device is flexibly designed and is suitable for shear tests on different slope soil and rock structures. It can effectively cope with the test problems caused by difficult-to-sample strata and sampling disturbances.

[0051] 6. Machine learning and numerical simulation: Verify the accuracy of experimental results using historical experimental data and finite element analysis.

[0052] In summary, the in-situ compression-shear test device and method for slope rock and soil provided by this invention have significant advantages such as high precision, low cost, high efficiency, and strong adaptability, providing reliable technical support for slope stability analysis and support design. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the in-situ compression-shear test device for slope rock and soil of the present invention;

[0054] Figure 2 This is a flowchart of the in-situ compression-shear test method for slope rock and soil of the present invention;

[0055] Figure 3 This is a schematic diagram of the pressure variation curve of the pressure plate of the present invention with displacement;

[0056] Figure 4 This is a schematic diagram of the shearing surface of the present invention;

[0057] Figure 5 This is a schematic diagram illustrating the decomposition of pressure along the shear plane in the pressure plate of the present invention;

[0058] Figure 6 This is a schematic diagram of the fitting line for the shear strength of soil under different compression-shear angles according to the present invention;

[0059] In the figure, 1—foundation soil, 2—fixed base, 3—level bubble, 4—anchor bolt, 5—multi-link structure, 6—first support rod, 7—second support rod, 8—third support rod, 9—pressure application component, 10—hydraulic jack, 11—pressure plate, 12—hydraulic servo system, 13—test soil sample, 14—shear surface. Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0061] For ease of explanation, spatial relative terms such as “above,” “below,” “left,” and “right” may be used herein to describe the relationship of one element or feature shown in the figure relative to another element or feature. It should be understood that, in addition to dealing with the orientation shown in the figure, spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figure is inverted, an element described as being “below” other elements or features would be defined as being “above” other elements or features. Therefore, the exemplary term “below” can encompass both above and below. The device may be positioned in other ways, and the spatial relative descriptions used herein can be interpreted accordingly.

[0062] To address the problems of disturbance, sampling difficulties, and data deviation in traditional testing methods, this embodiment proposes an in-situ compression-shear testing device for slope soil and rock. For example... Figure 1As shown, the in-situ compression-shear test device for slope soil includes a fixed base 2 that is horizontally fixed to the foundation soil 1 by anchor bolts 4. A pressure application component 9 is installed on the fixed base 2 by a multi-link structure 5, and the pressure application component 9 extends to the side of the test soil sample 13 to apply pressure to the test soil sample 13.

[0063] like Figure 1 As shown, the fixed base 2 in this embodiment is a rectangular plate structure with a spirit level 3 embedded in the center of its top surface and mounting holes for the anchor bolts 4 to pass through at its four corners. The fixed base 2 is used to support the entire test device and is fixed to the foundation soil 1. The spirit level 3 is used to detect whether the test base is level. The anchor bolts 4 can firmly fix the fixed base 2 to the foundation soil 1. The fixed base 2 ensures the levelness of the test device and provides a stable reaction force foundation for the subsequent pressure system.

[0064] like Figure 1 As shown, the multi-link structure 5 in this embodiment includes three first support rods 6 arranged in a triangle. One end of each first support rod 6 is mounted on the fixed base 2 via a hinged seat. The other ends of the three first support rods 6 converge at a point and are hinged to one end of a third support rod 8. A pressure application component 9 is mounted on the other end of the third support rod 8. The multi-link structure 5 also includes a second support rod 7. One end of the second support rod 7 is hinged to the middle section of the third support rod 8, and the hinge point position can be changed. Its other end is hinged to one of the three first support rods 6. The multi-link structure 5 provides support and angle adjustment functions, allowing the pressure application component 9 to flexibly adapt to the test requirements of different tilt angles.

[0065] like Figure 1 As shown, the pressure application component 9 in this embodiment includes a hydraulic jack 10 installed at the other end of the third support rod 8, and a hydraulic servo system 12 connected to the hydraulic jack 10 via pipelines; a pressure plate 11 is installed on the telescopic rod of the hydraulic jack 10. The hydraulic servo system 12 provides stable pressurizing power; the hydraulic jack 10 applies pressure; the pressure plate 11 directly contacts the test soil sample 13 to apply pressure; the pressure application component 9, through the multi-link structure 5, can apply pressure to the test soil at different angles until the soil undergoes shear failure.

[0066] Furthermore, the in-situ compression-shear test device for slope soil and rock also includes a pressure sensor, an inclination sensor, a laser displacement rangefinder, a laser scanner, an analog-to-digital converter, and an industrial computer. The pressure sensor is mounted on the hydraulic jack 10, the inclination sensor is mounted on the connecting pipe between the pressure plate 11 and the hydraulic jack 10, and the laser scanner and analog-to-digital converter are independently mounted near the test soil sample 13. The pressure sensor, inclination sensor, laser displacement rangefinder, and analog-to-digital converter are wired together, and the industrial computer is wired together with the analog-to-digital converter, laser scanner, and pressure application component 9. The hydraulic servo system 12 is wired together with the industrial computer.

[0067] The system includes a pressure sensor to measure the pressure applied by the pressure plate 11; an inclination sensor to measure the inclination angle of the pressure plate 11; a laser displacement rangefinder to measure the displacement of the test soil during pressurization; pressure data, inclination angle data, and displacement data of the test soil are converted into digital signals by an analog-to-digital converter and transmitted to an industrial computer; a laser scanner for three-dimensional modeling of the shear surface and calculation of the shear surface area; and an industrial computer for real-time processing and analysis of the data collected by the sensors, as well as for controlling the hydraulic servo system 12. By collecting pressure, displacement, inclination angle, and other data in real time during the test, accurate basic data is provided for subsequent analysis. Simultaneously, automated control of the test process reduces human error and improves test accuracy.

[0068] Based on the aforementioned in-situ compression-shear test device for slope rock and soil, this embodiment also proposes an in-situ compression-shear test method for slope rock and soil, such as... Figure 2 As shown, the in-situ compression-shear test method for this slope soil and rock mass includes the following steps:

[0069] S1 soil sample preparation:

[0070] First, an experimental platform was excavated on the experimental slope;

[0071] Then, three sets of truncated pyramidal soil samples were prepared on the same geological layer:

[0072] The bottom and top surfaces of test soil sample 13 are similar quadrilaterals, and the sides are trapezoidal; the height of the truncated pyramid is 20cm to 40cm; one of the axes of test soil sample 13 is consistent with the slope direction.

[0073] Finally, the pressure surface was trimmed on the upper slope side of each group of test soil samples 13:

[0074] The inclination angles of the pressure surfaces of the soil samples in each group differ by 10° to 15°; the pressure surfaces are repaired and leveled to ensure close contact with the pressure plate 11.

[0075] Prepare a truncated pyramid shape for the soil sample 13 to prevent it from breaking at the bottom during compression and shearing. Set up pressure surfaces with different inclination angles to study the mechanical properties of the soil under different shear angles. Ensure that the soil sample 13 is undisturbed to reflect the true mechanical properties of the soil.

[0076] S2 device installation:

[0077] First, install the fixed base 2. Install the fixed base 2 on the slope side of the test soil sample 13 and adjust the level bubble 3 to make the base horizontal. Tighten the anchor bolts 4 to firmly fix the fixed base 2 on the foundation soil 1.

[0078] Then follow Figure 1 As shown, the three first support rods 6 of the multi-link structure 5 are installed. After the first support rods 6 are installed, the second support rods 7 and the third support rods 8 and the pressure application component 9 are installed. After the multi-link structure 5 and the pressure application component 9 are installed, the angle of the pressure application component 9 is adjusted by the multi-link structure 5 so that the pressure plate 11 is in close contact with the pressure surface of the test soil sample 13.

[0079] Finally, install the pressure sensor, tilt sensor, laser displacement rangefinder, laser scanner, analog-to-digital converter, and industrial computer; turn on the tilt sensor, laser displacement rangefinder, and laser scanner to ensure the equipment is operating normally.

[0080] The fixed base 2 ensures the stability of the test apparatus, providing a reliable reaction force foundation for subsequent pressurization. The multi-link structure 5 and the pressure application component 9 work together to ensure that the pressurization direction and angle meet the test requirements. Pressure sensors, tilt sensors, and laser displacement rangefinders collect test data in real time, providing accurate basic information for subsequent analysis.

[0081] S3 Data Acquisition and Pressurization:

[0082] Start the hydraulic servo system 12, and control the hydraulic servo system 12 of the pressure application component 9 through the industrial computer, so that the hydraulic jack 10 of the pressure application component 9 applies pressure to the test soil sample 13 at a uniform speed.

[0083] During data acquisition and pressurization, the following data are recorded in real time:

[0084] The pressure sensor measures the pressure data F applied by the hydraulic jack 10, the tilt sensor measures the tilt data θ1 of the pressure plate 11, and the laser displacement rangefinder measures the displacement data S of the test soil during the pressurization process. The pressure data F, tilt data θ1, and displacement data S of the test soil are converted into digital signals by an analog-to-digital converter and transmitted to an industrial computer.

[0085] Uniform pressure is applied to simulate the stress conditions under actual engineering conditions. Pressure, displacement, and tilt angle data are collected in real time to comprehensively record the stress and deformation process of the soil.

[0086] S4 Shear Destruction and Recording:

[0087] Continuously apply pressure until test soil sample 13 fails in shear, and record the maximum pressure data and the displacement data of test soil sample 13 at failure; measure the geometric parameters of shear surface 14 using a laser scanner and calculate the area of ​​shear surface 14; the specific steps are as follows:

[0088] Step 4.1: Continue applying pressure until test soil sample 13 fails in shear. Record the pressure and displacement changes during the pressure application process until test soil sample 13 fails in shear. Generate a curve showing the change in pressure on the pressure plate 11 and the displacement of the test soil during the pressure application process. The curve is shown in Figure 4.1. Figure 3 As shown, the maximum pressure F recorded in the variation curve is... max and displacement S at failure max .

[0089] Step 4.2: After the test soil sample 13 fails under shear, remove the pressure plate 11; remove the soil above the shear surface 14, and use a laser scanner to create a 3D model of the shear surface 14, as shown in the image. Figure 4 As shown, measure the side lengths a, b, c, d and the diagonal length L of the shear surface 14, and calculate the area A of the shear surface 14.

[0090] The formula for calculating the cross-sectional area A is as follows:

[0091] A=[P1×(P1-a)×(P1-b)×(P1-L)] 0.5 +[P2×(P2-c)×(P2-d)×(P2-L)] 0.5

[0092] In the formula, P1 and P2 are intermediate variables, P1 = (a + b + L) / 2, P2 = (c + d + L) / 2;

[0093] Step 4.3: Attach the pressure plate 11 to the shear surface 14, measure the inclination angle θ2 of the normal of the shear surface 14, calculate the inclination angle α of the shear surface 14, and the pressure angle β between the shear surface 14 and the pressure plate 11.

[0094] The formula for calculating the inclination angle α of the shear plane 14 is as follows:

[0095] α = 90° - θ²

[0096] The formula for calculating the pressure angle β between the shear plane 14 and the pressure plate 11 is as follows:

[0097] β=θ1-α

[0098] Recording key parameters of soil shear failure provides a basis for subsequent mechanical analysis. Precise measurement of the geometric characteristics of shear plane 14 using laser scanning technology ensures data accuracy. Calculating the inclination angle and pressure angle of shear plane 14 lays the foundation for calculating mechanical parameters.

[0099] S5 Data Analysis and Parameter Calculation:

[0100] The compressive and shear stresses on the shear surface 14 of the test soil sample 13 are calculated using an industrial computer, and a σ-τ straight line is fitted to extract the internal friction angle and cohesion. The specific steps are as follows:

[0101] Step 5.1, the decomposed schematic diagram of the pressure of the pressure plate 11 along the shear plane 14 is shown below. Figure 5 As shown, firstly, the compressive stress σ and shear stress τ on shear plane 14 are calculated:

[0102]

[0103] In the formula, σ represents the normal stress on the shear plane 14; F n The maximum pressure F applied to the pressure plate 11 max The normal component along the shear plane; A is the area of ​​shear plane 14; β is the angle between shear plane 14 and the pressure of pressure plate 11; F max Maximum pressure during pressurization; τ represents the tangential stress on shear plane 14; F t The maximum pressure F applied to the pressure plate 11 max Tangential components decomposed along the shear plane.

[0104] Step 5.2: Perform compression-shear tests on soil samples 13 with different inclination angles to obtain multiple sets of σ. i τ i data;

[0105] Step 5.3: Use a multi-parameter fitting model to fit the σ-τ line, as shown in Figure 5.3. Figure 6 As shown; then, calculate the internal friction angle φ and cohesion c of the soil;

[0106] The calculation formula is: τ=c+σ·tanφ;

[0107] In the formula, φ is the angle between the fitted σ-τ line and the abscissa, i.e., the internal friction angle; c is the intersection of the fitted σ-τ line and the ordinate, i.e., the cohesion.

[0108] By fitting the σ-τ line to multiple sets of experimental data, the key mechanical parameters of the soil, namely the internal friction angle and cohesion, are extracted, enabling data analysis and parameter calculation to provide accurate shear strength indicators for slope stability analysis.

[0109] S6 Test Termination and Dismantling:

[0110] The test will be stopped after the data analysis system issues a test termination message. The test equipment will be dismantled, and the site cleaned up. Ensure the test is completed safely to avoid impacting the slope environment.

[0111] This in-situ compression-shear test method for slope soil and rock masses achieves in-situ testing of the shear strength of slope soil and rock masses through the above steps, specifically including soil sample preparation, device installation, data acquisition, shear failure recording, data analysis, numerical simulation, and test termination. Each step has a clear function and together constitutes a complete test procedure. This method can effectively solve problems such as sampling disturbance and shear plane deviation existing in traditional tests, providing scientific and reliable technical support for slope stability analysis.

[0112] Furthermore, this in-situ compression-shear test method for slope soil and rock can be combined with numerical simulation technology to verify the accuracy of the test results through finite element analysis and provide more comprehensive mechanical parameters.

[0113] Specifically, historical test data, including the pressure data F applied by the hydraulic jack 10, the displacement data S of the test soil, the inclination data of the pressure plate 11, the inclination angle of the normal of the shear surface 14, the area A of the shear surface 14, the compressive stress on the shear surface 14, and the shear stress on the shear surface 14, are imported into a machine learning model to train an algorithm to predict the shear failure mode and mechanical properties of the soil. Then, combined with finite element analysis, the accuracy of the test results is verified, and the slope stability is evaluated.

[0114] Machine learning models are used to uncover patterns in data, improving our understanding of soil mechanical properties. Finite element analysis is used to verify the reliability of experimental results, providing a scientific basis for slope stability assessment.

[0115] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An in-situ compression-shear test device for slope rock and soil, characterized in that: The in-situ compression-shear test device for slope soil and rock includes a fixed base horizontally fixed to the foundation soil by anchor bolts. A pressure-applying component is installed on the fixed base via a multi-link structure, extending to the test soil sample side to apply pressure. The device also includes a pressure sensor, an inclination sensor, a laser displacement rangefinder, a laser scanner, an analog-to-digital converter (ADC), and an industrial computer. The pressure sensor and inclination sensor are mounted on the pressure-applying component, while the laser scanner and ADC are independently mounted near the test soil sample. The pressure sensor, inclination sensor, and laser displacement rangefinder are wired to the ADC. The laser displacement rangefinder is used to measure the displacement of the test soil during pressurization. The industrial computer is wired to the ADC, laser scanner, and pressure-applying component. The multi-link structure includes three first support rods arranged in a triangle. One end of each first support rod is mounted on a fixed base via a hinged seat. The other ends of the three first support rods converge at a point and are hinged to one end of a third support rod. A pressure-applying component is mounted on the other end of the third support rod. The multi-link structure also includes a second support rod. One end of the second support rod is hinged to the middle section of the third support rod, and the hinge point position can be changed. Its other end is hinged to one of the three first support rods. The pressure application assembly includes a hydraulic jack installed at the other end of the third support rod, and a hydraulic servo system connected to the hydraulic jack pipeline; a pressure plate is installed on the telescopic rod of the hydraulic jack.

2. The in-situ compression-shear test device for slope rock and soil according to claim 1, characterized in that: The fixed base is a rectangular plate structure with a spirit level embedded in the center of its top surface and mounting holes at its four corners for anchor bolts to pass through.

3. The in-situ compression-shear test device for slope rock and soil according to claim 1, characterized in that: The hydraulic servo system is wired to an industrial computer.

4. A method for in-situ compression-shear testing of slope rock and soil, wherein the method is based on the in-situ compression-shear testing apparatus for slope rock and soil as described in any one of claims 1-3, characterized in that, Includes the following steps: S1 Soil Sample Preparation: Excavate a platform on the slope and prepare 3 sets of test soil samples in the shape of a truncated pyramid. Trim the pressure surface on the slope side of each set of test soil samples. The inclination angle of the pressure surface of each set of soil samples differs by 10°~15° to ensure that it can fit flat and adhere to the pressure plate. S2 device installation: Install the fixed base on the foundation soil and adjust the fixed base to be level; install the multi-link structure and pressure application component based on the fixed base, and adjust the angle of the pressure application component through the multi-link structure; turn on the tilt sensor, laser displacement rangefinder and laser scanner to ensure normal operation of the equipment; S3 Data Acquisition and Pressurization: The hydraulic servo system is activated by an industrial computer to apply pressure at a constant speed, and pressure data, test soil sample displacement data and pressure component tilt angle data are recorded in real time. S4 Shear Failure and Recording: Apply pressure continuously until the test soil sample fails in shear, record the maximum pressure data and the displacement data of the test soil sample at failure; use a laser scanner to measure the geometric parameters of the shear surface, and calculate the shear surface area and inclination angle; S5 Data Analysis and Parameter Calculation: The compressive stress σ and shear stress τ on the shear surface of the test soil sample are calculated by an industrial computer, the σ-τ line is fitted, and the internal friction angle and cohesion are extracted. S6 Test Termination and Dismantling: After the data analysis system issues a test termination message, stop the test; dismantle the test equipment and clean up the site.

5. The in-situ compression-shear test method for slope rock and soil according to claim 4, characterized in that: During S3 data acquisition and pressurization, the pressure sensor measures the pressure data F applied by the hydraulic jack, and the tilt sensor measures the tilt angle data of the pressure plate. A laser displacement rangefinder was used to measure the displacement data S, pressure data F, and inclination angle data of the test soil during the pressurization process. The displacement data S of the test soil is converted into a digital signal by an analog-to-digital converter and transmitted to an industrial computer.

6. The in-situ compression-shear test method for slope rock and soil according to claim 5, characterized in that: S4 shear destruction and recording, including the following steps: Step 4.1: Continue applying pressure until the test soil sample fails under shear. Record the pressure and displacement changes during the pressure application process until the test soil sample fails under shear. Generate a curve showing the change in pressure on the pressure plate versus the displacement of the test soil during the pressure application process. Based on the maximum pressure recorded in the curve... and displacement at the time of failure ; Step 4.2: After the soil sample fails under shear, remove the pressure plate, remove the soil above the shear surface, use a laser scanner to create a 3D model of the shear surface, and measure the side length of the shear surface. Given b, c, d and the diagonal length L, calculate the area A of the shear surface; The formula for calculating the cross-sectional area A is as follows: ； In the formula, , As an intermediate variable, , ; Step 4.3: Attach the pressure plate to the shear surface and measure the angle of inclination of the normal to the shear surface. Calculate the shear plane inclination angle And the angle between the shear plane and the pressure of the pressure plate. ; Shear plane inclination angle The calculation formula is as follows: ； Angle between the shear plane and the pressure plate The calculation formula is as follows: 。 7. The in-situ compression-shear test method for slope rock and soil according to claim 5, characterized in that: S5 data analysis and parameter calculation include the following steps: Step 5.1, calculate the compressive stress on the shear plane. and shear stress : ； ； In the formula, This represents the normal stress on the shear plane; Maximum pressure applied to the pressure plate The normal components of the decomposition; The area of ​​the shear surface; The angle between the shear plane and the pressure of the pressure plate; This is the maximum pressure during the pressurization process; This represents the tangential stress on the shear plane; Maximum pressure applied to the pressure plate The tangential component of the decomposition; Step 5.2: Conduct compression-shear tests on soil samples with different inclination angles to obtain multiple sets of results. , data; Step 5.3: Use a multi-parameter fitting model to fit the data. - Straight line, calculate the internal friction angle of the soil. and cohesion c; The calculation formula is: ; In the formula, For fitting - The angle between the straight line and the x-axis is the angle of internal friction; c is the fitted angle. - The intersection of the straight line and the vertical axis represents the cohesion.

8. The in-situ compression-shear test method for slope rock and soil according to claim 5, characterized in that: The in-situ compression-shear test method for slope soil and rock also includes: S7 Machine Learning and Numerical Simulation: This involves combining historical experimental data such as the pressure F applied by the hydraulic jack, the displacement S of the test soil, and the inclination angle data of the pressure plate. Measure the inclination angle of the shear plane normal Shear surface area A, compressive stress on the shear surface and shear stress on the shear plane A machine learning model was imported to train an algorithm that predicts soil shear failure modes and mechanical properties. Then, finite element analysis was used to verify the accuracy of the test results and to evaluate slope stability.

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