Rock-soil mass seepage-stress coupling visualization device and test method thereof

Abstract

The invention relates to the technical field of rock / soil mass seepage-stress coupling, and discloses a rock-soil mass seepage-stress coupling visualization device and a test method thereof. The rock-soil body seepage-stress coupling visualization device integrates a seepage pressure system controlled by a high-precision plunger pump, a confining pressure and back pressure control system, a loading and measuring device and a visualization observation system composed of a PIV particle image measuring instrument and a three-dimensional XTDIC full-field strain measuring system, and an experiment platform with comprehensive and accurate functions is formed. The device not only can accurately control and measure the seepage pressure, but also can carry out permeability research on the rock / soil body in various stress states, and directly observes and records the seepage field and the structural evolution process in the rock / soil body through an intuitive visual means. The device not only improves the experiment efficiency, but also greatly enhances the intuition and accuracy of research, and provides powerful support for deeply understanding the microscopic and macroscopic behaviors of the rock / soil body under the seepage-stress coupling action.

Description

Technical Field

[0001] The present invention belongs to the technical field of seepage-stress coupling of rock / soil mass, and particularly relates to a visualization device for seepage-stress coupling of rock and soil mass and an experimental method thereof. Background Technique

[0002] In practical engineering, rock / soil mass and its interface (some special places where structures are adjacent to soil mass) are weak surfaces in engineering (the material properties of soil and structures are very different), and are extremely prone to seepage failure. Seepage is often accompanied by particle migration, which usually causes structural instability and water inrush disasters. Particle migration and porosity evolution have a significant impact on the formation of seepage channels. There is a relationship between the change of rock mass fissures and the unloading amount: after the rock mass is unloaded, the internal cracks will merge, develop, converge, and finally form large fissures, which are basically perpendicular to the unloading direction of the rock mass, forming the main controlled single fissure, that is, the seepage channel of the rock mass, resulting in a large increase in the permeability of the rock mass. Once seepage occurs in rock / soil mass and its interface, it may be irreparable. However, there are few studies on the analysis of the seepage mechanism of rock / soil mass and its interface. Therefore, it is very important to explore the seepage mechanism of rock / soil mass. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above problems, and provide a visualization device for seepage-stress coupling of rock and soil mass and an experimental method thereof, which can directly observe the action process of seepage-stress coupling in rock / soil mass and its junction, provide basic data for obtaining numerical simulation and mechanism analysis of seepage-stress coupling of rock / soil mass and its interface, and provide support for studying the evolution of seepage characteristics and stress-strain constitutive mathematical models of rock / soil mass and its interface.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions: The present invention provides a visualization device for seepage-stress coupling of rock and soil mass, including a seepage pressure control device, a confining pressure and back pressure control device, a loading and measuring device, and a visualization observation device; The seepage pressure control device includes a high-precision plunger pump and a seepage inlet and outlet pipeline system, and the high-precision plunger pump is connected to the seepage inlet and outlet pipeline system for controlling and measuring the seepage pressure; The confining pressure and back pressure control device includes a confining pressure control device and a back pressure control device, and both the confining pressure control device and the back pressure control device are connected to a transparent confining chamber for applying and adjusting the confining pressure and back pressure; The loading and measuring device includes a transparent confining chamber and an axial loading device, the transparent confining chamber is arranged below the axial loading device, and a transparent specimen is arranged in the transparent confining chamber; The visualization observation device includes a PIV particle image measurement instrument and a three-dimensional XTDIC full-field strain measurement system. Both the PIV particle image measurement instrument and the three-dimensional XTDIC full-field strain measurement system are arranged outside the transparent confining chamber and are used to observe and record the seepage field and structural evolution inside the rock / soil mass.

[0005] A further improvement of the present invention lies in that the seepage inlet and outlet pipeline system includes a bottom seepage channel, a top seepage channel and an external water tank communicated therewith. The bottom seepage channel, the top seepage channel and the external water tank are all connected to a high-precision plunger pump.

[0006] A further improvement of the present invention lies in that pressure and displacement sensors are arranged below the axial loading device.

[0007] A further improvement of the present invention lies in that it further includes a pressurizing top cap and a three-way converter. The pressurizing top cap is arranged above the transparent specimen, and the three-way converter is connected to the bottom of the transparent specimen.

[0008] A further improvement of the present invention lies in that the confining pressure control device is connected to the hydraulic oil inside the transparent confining chamber through a hydraulic pipeline system; the back pressure control device enters the transparent confining chamber through a pipeline and applies an axial back pressure to the top of the transparent specimen through the pressurizing top cap on the upper part of the transparent specimen.

[0009] A further improvement of the present invention lies in that a catcher is arranged on the outer side of the transparent confining chamber. A CCD camera and a three-dimensional XTDIC full-field strain measurement system are arranged on one side of the catcher away from the transparent confining chamber; both the CCD camera and the three-dimensional XTDIC full-field strain measurement system are connected to a computer.

[0010] A further improvement of the present invention lies in that the PIV particle image measurement instrument includes a CCD camera and a laser emission light source.

[0011] The present invention also provides a test method for a rock and soil mass seepage-stress coupling visualization device, including the following steps: S1, collecting rock / soil mass specimens and making transparent specimens based on the replicated transparent fracture technology and the transparent soil technology; S2, placing the transparent specimen in the transparent confining chamber, injecting the prepared pore fluid into the water supply device and adding a fluorescent agent; S3, opening the seepage inlet and outlet pipeline system to enable the pore fluid to enter the device interior and starting the PIV particle image measurement instrument; S4, adjusting the confining pressure control device and the back pressure control device, applying a preset confining pressure and back pressure, and starting the axial loading device to apply an axial load to the transparent specimen; S5, using the PIV particle image measurement instrument and the three-dimensional XTDIC full-field strain measurement system to record the seepage field and structural evolution.

[0012] A further improvement of the present invention lies in that the steps for preparing the transparent specimen are as follows: S11, obtaining the rock / soil structure characteristics, including fracture structure, pore characteristics, mineral composition, and fracture surface characteristics; S12, fabricating a transparent fractured rock specimen and a transparent soil specimen, and combining the transparent soil specimen with the transparent fractured rock specimen to form a transparent specimen of the rock / soil interface.

[0013] A further improvement of the present invention lies in that the multi-phase and multi-directional seepage experiment of the rock / soil and the interface under triaxial stress conditions is carried out by using this test method, with the confining pressure set at 0 - 20 MPa, the axial displacement at 0 - 20 mm, and the osmotic pressure at 0 - 40 MPa.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a visualization device for the seepage-stress coupling of rock and soil. By integrating a seepage pressure system controlled by a high-precision plunger pump, a confining pressure and back pressure control system, a loading and measuring device, and a visualization observation system composed of a PIV particle image measuring instrument and a three-dimensional XTDIC full-field strain measuring system, a comprehensive and accurate experimental platform is formed. This device can not only accurately control and measure the seepage pressure, but also study the permeability of rock / soil under various stress states. Through intuitive visualization means, the seepage field and the structural evolution process inside the rock / soil can be directly observed and recorded. This device not only improves the experimental efficiency, but also greatly enhances the intuitiveness and accuracy of the research, providing strong support for deeply understanding the microscopic and macroscopic behaviors of rock / soil under the seepage-stress coupling effect.

[0015] The present invention also provides a test method for the visualization device of the seepage-stress coupling of rock and soil. This method is simple to operate and can efficiently record the structural evolution process of the soil / rock mass, and can more intuitively and efficiently study the seepage-stress coupling effect of the rock / soil and the interface to obtain the evolution process of the permeability characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present invention disclosure in any way. Additionally, the shapes and proportional dimensions of the components in the drawings are only schematic and are used to assist in understanding the present invention, rather than specifically limiting the shapes and proportional dimensions of the components of the present invention.

[0017] Figure 1 is the visualization test device for the seepage-stress coupling of the rock / soil of the present invention; Figure 2(a) is a schematic diagram of the production of the transparent replicated rock sample of the present invention; Figure 2(b) is a schematic diagram of the production of the transparent replicated soil sample of the present invention; Figure 2(c) is a schematic diagram for fabricating a transparent replicated interlayer geotechnical specimen of the present invention; Figure 2(d) is a schematic diagram for fabricating a transparent replicated rock mass / concrete slab - soil interface specimen of the present invention; Figure 3 is a flowchart for preparing the transparent specimen of the present invention; Figure 4(a) is a schematic diagram of a transparent soil material of the present invention; Figure 4(b) is a schematic diagram of another transparent soil material of the present invention.

[0018] Wherein: 1. High-precision plunger pump; 2. Seepage inlet and outlet pipeline system; 3. Transparent confining pressure chamber; 4. Confining pressure control device; 5. Axial loading device; 6. CCD camera; 7. Laser emission light source; 8. Three-dimensional XTDIC full-field strain measurement system; 9. Catcher; 10. Computer; 11. Back pressure control device; 12. Pressing top cap; 13. Hydraulic pipeline system; 14. Pressure and displacement sensors; 15. Three-way converter; 16. External water tank. Detailed implementation manners

[0019] The present invention will be further described in detail below with reference to the accompanying drawings: As Figure 1 shown, the present invention provides a geotechnical seepage - stress coupling visualization device, including a seepage pressure control device, a confining pressure and back pressure control device, a loading and measurement device, and a visualization observation device. The seepage pressure control device includes a high-precision plunger pump 1 and a seepage inlet and outlet pipeline system 2; the confining pressure and back pressure control device includes a confining pressure control device 4 and a back pressure control device 11; the loading and measurement device includes a transparent confining pressure chamber 3 and an axial loading device 5; the visualization observation device includes a PIV particle image measurement instrument and a three-dimensional XTDIC full-field strain measurement system 8.

[0020] The high-precision plunger pump 1 is located on one side of the device. Through a precise sealing design, it ensures a stable output of flow under high pressure. The output end of the high-precision plunger pump 1 is connected to the seepage inlet and outlet pipeline system 2 through a pipeline for controlling and measuring the seepage pressure; the seepage inlet and outlet pipeline system 2 includes a bottom seepage channel, a top seepage channel, and an external water tank 16 connected thereto. They are responsible for introducing or discharging the liquid medium into or out of the high-precision plunger pump 1 to achieve the liquid circulation; in particular, the bottom seepage channel and the top seepage channel are connected to the external water tank 16, and the external water tank 16 provides sufficient seepage liquid for the seepage inlet and outlet pipeline system 2.

[0021] The transparent confining pressure chamber 3 is located at the center of the device and is used to accommodate the transparent specimen in the test. The four walls of the transparent confining pressure chamber 3 are transparent, facilitating observation and measurement. An axial loading device 5 is provided at the top of the transparent confining pressure chamber 3. By starting the motor, the transparent confining pressure chamber 3 is lifted or lowered to apply or release the axial force. In addition, a pressure cap 12 is located above the transparent specimen and is connected to the pipeline of the back pressure control device 11. The pipeline of the back pressure control device 11 directly enters the interior of the transparent confining pressure chamber 3, and an axial back pressure is applied to the top of the transparent specimen through the pressure cap 12 on the upper part of the transparent specimen.

[0022] The confining pressure control device 4 is connected to the hydraulic oil in the transparent confining pressure chamber 3 through the hydraulic pipeline system 13. The hydraulic pipeline system 13 ensures that the confining pressure can act on the specimen evenly and stably. It should be noted that the controls of the confining pressure control device 4 and the back pressure control device 11 are independent of each other, but they act together on the specimen to simulate the real stress environment.

[0023] A three-dimensional XTDIC full-field strain measurement system 8 and a matching CCD camera 6 are provided on the right side of the transparent confining pressure chamber 3. The three-dimensional XTDIC full-field strain measurement system 8 is used to record the evolution process of the soil / rock mass structure. This system captures the deformation images on the surface of the specimen and calculates the three-dimensional coordinates, displacements, and strain results. At the same time, the CCD camera 6 and the laser emission light source 7 form a PIV particle image measuring instrument. They illuminate the fluorescent particles in the seepage field and capture their images to realize the visualization of the seepage field.

[0024] Specifically, the specific operation steps for the visualization of the seepage field and the strain field are as follows: Step 1, system preparation: Use the PIV particle image measuring instrument to add fluorescent particles with a diameter of 5 - 10 μm as tracers to the seepage liquid. The seepage liquid uses distilled water, and it is ensured that the seepage liquid will not react with the fluorescent particles. Step 2, during the loading process of the transparent specimen, the three-dimensional XTDIC full-field strain measurement system 8 synchronously collects images and synchronously records the analog signals transmitted by the testing machine. When measuring, a double-pulse green Nd:YAG laser with a maximum energy of 30 mJ / pulse is used to form a laser sheet with a thickness of about 0.8 mm to illuminate the tracer particles in the flow domain and display them on the screen of the catcher 9. Step 3, calculation and analysis: The three-dimensional XTDIC full-field strain measurement system 8 automatically calculates the three-dimensional coordinates of the transparent specimen in all loading stages, obtains the geometric surface, displacement, and strain results, calculates the material property parameters, imports them into CAD for comparison and analysis, calculates the geometric elements, calculates the external analog signals, imports the finite element theory to calculate the numerical values, and compares and analyzes them with the measured results, and outputs the results on the computer 10. Step 4, Seepage field visualization: Use relevant methods and combine with dynamic simulation evolution to achieve the visualization goal of the seepage field. Mainly use methods such as vector line method, feature method, texture method, and point arrow method to realize the visualization of the seepage field; Step 5, Measurement report: The three-dimensional XTDIC full-field strain measurement system 8 generates a measurement report, including three-dimensional views, curves, charts, and videos, etc., and exports the test data in a standard format. During the experiment, turn on the data acquisition system to collect data such as axial force, deformation pictures of the transparent specimen surface, and top and bottom flow rates until the rock / soil transparent specimen is damaged and the test ends.

[0025] In addition, the pressure and displacement sensors 14 are connected to the top of the transparent specimen and are located below the axial loading device 5 for real-time monitoring of the pressure and displacement changes of the transparent specimen; the three-way converter 15 is connected to the bottom of the transparent specimen for connecting different pipeline systems to provide flexible pipeline connection options for the device.

[0026] A catcher 9 is arranged outside the transparent confining chamber 3. The catcher 9 is located behind the CCD camera 6 and is used to receive and display the images captured by the CCD camera 6. Both the CCD camera 6 and the three-dimensional XTDIC full-field strain measurement system 8 are connected to the computer 10 for storing, processing, and analyzing the measurement data.

[0027] The PIV particle image measuring instrument includes a CCD camera 6 and a laser emission light source 7. The CCD camera 6 is used to capture the fluorescence particle images in the seepage field, while the laser emission light source 7 is responsible for illuminating the seepage field; among them, the CCD camera 6, the laser emission light source 7, and the three-dimensional XTDIC full-field strain measurement system 8 are all arranged outside the transparent confining chamber 3 for observing and recording the seepage field and structural evolution inside the rock / soil body.

[0028] The present invention also provides a test method for a rock / soil seepage-stress coupling visualization device, including the following steps: Step S1, Specimen preparation: Collect rock / soil specimens for typical projects. Perform Brazilian splitting (MTS 815) on the cuboid rock specimen to obtain the fracture structure in the rock formation; use the replica transparent fracture technology and transparent soil technology to produce a visualization test transparent specimen; Step S2, Place the transparent specimen in the transparent confining chamber 3, inject the prepared pore fluid into the water supply device and add a fluorescent agent; Step S3, Open the inlet valve and outlet valve of the seepage inlet and outlet pipeline system 2 to allow the pore fluid to enter the inside of the transparent confining chamber 3 through the permeable plate. Start the PIV particle image measuring instrument, turn on the laser emission light source 7 and adjust the laser section angle so that it vertically enters the saturated transparent specimen to form a speckle field and projects onto the catcher 9; Step S4: Adjust the confining pressure control device 4 and the back pressure control device 11, set the confining pressure of the transparent specimen to a fixed value, and apply axial pressure to the top of the specimen through the upper pressure cap 12 of the specimen. Step S5: Turn on the CCD camera 6 and adjust the visual range to include the entire transparent specimen. Then, move the laser emission light source 7 slowly and uniformly along the guide rail slider to take pictures, and extract the cross-sectional slice images for the later three-dimensional reconstruction of the transparent specimen. Step S6: Turn on the water pump, control the height of the external water tank 16 so that the saturated transparent specimen undergoes piping under a constant water head. At the same time, transmit the data of the flowmeter and the pore pressure gauge to the computer 10 for data processing and analysis, and reveal the seepage-stress coupling mechanism of the rock / soil body transparent specimen.

[0029] As a preferred solution, the light source of the laser emission light source 7 is an X-ray light source.

[0030] The steps for preparing the transparent specimen are as follows: Step S11: Obtain the structural characteristics of the rock / soil body, specifically including using a non-contact 3D profile scanner (OKIO 5MPlus) and a CT scanner to obtain the roughness and spatial aperture of the rock sample fracture wall surface; obtaining the internal pore structure and distribution characteristics of the rock / soil body through MRI scanning technology; using an X-ray diffractometer (XRD) and a three-dimensional laser scanner to measure the mineral composition, content, distribution, and wetting characteristics of the fracture surface of the rock / soil body; using MATLAB to reconstruct the three-dimensional image of the rock / soil body from the scanned data, and statistically analyzing the characteristic parameters of the fractures and pores. Step S12: Fabricate a transparent fractured rock mass specimen and a transparent soil specimen, and combine the transparent soil specimen with the transparent fractured rock mass specimen to form a transparent specimen of the rock / soil body interface. Specifically, the fabrication of the transparent specimen of the rock / soil body interface includes a transparent replicated rock sample, a transparent replicated soil sample, a transparent replicated interlayer rock and soil specimen, and a transparent replicated rock mass / concrete slab - soil interface specimen.

[0031] The transparent replicated rock sample uses 3D printing to reconstruct the transparent fractured rock mass specimen. The distribution in the fracture network is generated by the Monte Carlo method. The fracture length and dip angle follow the statistical distribution proposed by the study of natural fracture characterization, as shown in Figure 2(a). The midpoints of the fractures are evenly distributed within the region. The fracture length follows a lognormal distribution, and the dip angle follows a normal distribution. The aperture of the fractures is 200 ± 1 mm and is within the range of natural fractures. A vertical downward pressure load is applied to the upper cap at the top of the transparent replicated rock sample, and the base maintains the stability of the transparent replicated rock sample. A fracture is set in the middle of the transparent replicated rock sample, and an infiltration chamber is connected to the fracture for fluid infiltration during the test to simulate the seepage process of the rock mass.

[0032] The transparent replica soil sample is filled with transparent soil sample in the middle, as shown in FIG2 (b). The production process is to put crystal beads of different particle sizes into the porous fluid, measure the refractive index with the help of Abbe refractometer, and adjust the ratio of anhydrous ethanol and distilled water by dichotomy until the refractive index of the mixed liquid is basically consistent with that of the crystal beads.

[0033] The transparent replica sandwich rock and soil test sample is placed between two transparent rock samples, as shown in Figure 2 (c), or a concrete slab / transparent replica rock mass is inserted into a transparent soil sample, as shown in Figure 2 (d), to form a soft contact surface.

[0034] Furthermore, if Figure 3 As shown, the preparation of the transparent sample of the rock / soil interface includes raw material screening, aggregate optimization and fluid configuration, experimental proportioning, mixing and stirring, casting and vacuum treatment cycle, graded loading, consolidation molding, graded unloading, and finally demolding.

[0035] See Figure 4 (a) and Figure 4 (b), schematic diagrams of the successful preparation of transparent samples at the rock / soil interface. It can be seen from the figure that the transparent samples contain particles of various shapes and sizes. These larger particles are rock fragments with irregular shapes. The transparent samples also contain the following smaller particles, which are soil particles or fine sand. There are some fibrous soil or plant roots at the bottom of the transparent samples, which are slender. These transparent samples show the mixed state of rock and soil, which contain rock fragments, soil particles and some plant roots. These transparent samples are of great help in studying the interface characteristics of rock and soil, such as permeability and stability.

[0036] It should be noted that the seepage-stress coupling test requires the use of Matlab image toolbox to intercept the video shot by CCD camera 6 to obtain a two-dimensional slice set of transparent soil samples. Based on the MRI principle, Avizo software is used to stack and denoise the two-dimensional slice set in an orderly manner, perform binary segmentation on the bright pore fluid and dark particles, and use the volume rendering command to perform three-dimensional reconstruction on the processed two-dimensional slice set to obtain detailed information on the porosity and pore structure of the actual model.

[0037] It should be noted that the permeable plate, flow meter and piezometer mentioned in the present invention are all structures in the rock and soil seepage-stress coupling visualization device, and all three are arranged inside the seepage pressure control device, wherein the permeable plate is arranged above the flow meter, and the flow meter and piezometer are arranged side by side to measure flow data and water pressure.

[0038] To provide basic data for the numerical simulation and mechanism analysis of seepage-stress coupling in rock / soil masses and their interfaces, and to support the research on the evolution of the permeability characteristics and the constitutive mathematical models of stress-strain in rock / soil masses and their interfaces, based on the above-mentioned visualization test device and test method for seepage-stress coupling in rock / soil masses, multi-phase and multi-directional seepage experiments of rock / soil masses and their interfaces under triaxial stress conditions are carried out. Considering conditions such as muddy water seepage, consolidation stress, hydraulic gradient, and seepage direction, experimental studies on the permeability characteristics during the large deformation process of a series of main dam materials are carried out, and a series of triaxial compression-seepage coupling experiments on rocks under different confining pressure conditions are carried out. Contact seepage experiments are carried out after the contact surface of different dam construction soil materials is deformed under force, to study the permeability characteristics and anti-seepage characteristics after considering the shear deformation of multi-media contact surfaces such as soil-rock contact surfaces and soil-concrete contact surfaces, and to explore the seepage change law of dam construction soil materials under the action of unequal-directional stresses.

[0039] The technical indicators of this test system are: confining pressure 0 - 20 MPa, axial displacement 0 - 20 mm, and osmotic pressure 0 - 40 Mpa. According to the permeability of the rock and the requirements of the test time, the transient pressure pulse method or the steady-state method can be flexibly selected for the permeability test method, and distilled water can be selected as the seepage fluid. Radial strain rate is used for loading control until the specimen deforms and fractures, obtaining a series of stress-strain process curves and permeability-stress process curves of rock / soil masses and their interfaces under different confining pressure conditions, etc., to provide basic data for the numerical simulation and mechanism analysis of seepage-stress coupling in rock / soil masses and their interfaces, and to support the research on the evolution of the permeability characteristics and the constitutive mathematical models of stress-strain in rock / soil masses and their interfaces.

[0040] Table 1 Triaxial compression-seepage coupling experimental scheme for rock / soil masses and their interfaces

[0041] The present invention uses a visualization test system, combined with the numerical simulation results of the Fluent-EDEM finite element-discrete element coupling software, to reveal the strain stiffness trend and failure mode of geotechnical samples from a macroscopic scale, and to reveal the evolution process of seepage path evolution and strain damage distribution under the action of stress-seepage from a mesoscopic scale. The whole process dynamic critical conditions of crack initiation, propagation to instability of fractured rock masses under hydraulic coupling action are revealed. Focus on studying the influence of fine particle content and relative density on the occurrence conditions of piping in soils lacking intermediate gradation, study the changes in soil porosity, permeability, stiffness, and strength indexes caused by the loss of fine particles, construct characteristic hydraulic parameters that lead to the collapse and breakdown of soil masses and their interfaces, describe the spatio-temporal distribution characteristics of the evolution of the permeability of rock / soil masses and their interfaces, and comprehensively expound the mechanism of seepage-stress coupling action of rock / soil masses.

[0042] Upon reading the above description, many embodiments and many applications beyond the provided examples will be obvious to those skilled in the art. Therefore, the scope of this teaching should not be determined with reference to the above description, but rather should be determined with reference to the foregoing claims and the full scope of equivalents to which those claims are entitled. For completeness, all articles and references including patent applications and publications of announcements are incorporated herein by reference. Omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended to abandon such subject matter, nor should it be considered that the applicant has not considered such subject matter as part of the disclosed inventive subject matter.

[0043] The above is a further detailed description of the present invention. It cannot be determined that the specific implementation of the present invention is limited thereto. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should all be regarded as falling within the protection scope determined by the claims submitted for the present invention.

Claims

1. A visualization device for seepage-stress coupling of rock and soil masses, characterized in that, It includes an osmotic pressure control device, a confining pressure and back pressure control device, a loading and measuring device, and a visualization observation device; The osmotic pressure control device includes a high-precision plunger pump (1) and a seepage inlet and outlet pipeline system (2). The high-precision plunger pump (1) is connected to the seepage inlet and outlet pipeline system (2) for controlling and measuring the osmotic pressure; The confining pressure and back pressure control device includes a confining pressure control device (4) and a back pressure control device (11). The confining pressure control device (4) and the back pressure control device (11) are both connected to the transparent confining pressure chamber (3) for applying and adjusting the confining pressure and back pressure; The loading and measuring device includes a transparent confining pressure chamber (3) and an axial loading device (5). The transparent confining pressure chamber (3) is arranged below the axial loading device (5), and a transparent specimen is arranged inside the transparent confining pressure chamber (3); The visualization observation device includes a PIV particle image measuring instrument and a three-dimensional XTDIC full-field strain measuring system (8). The PIV particle image measuring instrument and the three-dimensional XTDIC full-field strain measuring system (8) are both arranged outside the transparent confining pressure chamber (3) for observing and recording the seepage field and structural evolution inside the rock / soil mass; 2. The seepage-stress coupling visualization device for rock and soil mass according to claim 1, characterized in that The seepage inlet and outlet pipeline system (2) includes a bottom seepage channel, a top seepage channel, and an external water tank (16) communicated therewith. The bottom seepage channel, the top seepage channel, and the external water tank (16) are all connected to the high-precision plunger pump (1); 3. A seepage-stress coupling visualization device for rock and soil masses according to claim 1, characterized in that A pressure and displacement sensor (14) is arranged below the axial loading device (5); 4. The visualization device for seepage-stress coupling of rock and soil mass according to claim 1, wherein It also includes a pressurizing top cap (12) and a three-way converter (15). The pressurizing top cap (12) is arranged above the transparent specimen, and the three-way converter (15) is connected to the bottom of the transparent specimen; 5. A seepage-stress coupling visualization device for rock and soil masses according to claim 1 or 4, characterized in that, The confining pressure control device (4) is connected to the hydraulic oil inside the transparent confining pressure chamber (3) through a hydraulic pipeline system (13); the back pressure control device (11) enters the transparent confining pressure chamber (3) through a pipeline and applies an axial back pressure to the top of the transparent specimen through the upper pressurizing top cap (12) of the transparent specimen; 6. The visualization device for seepage-stress coupling of rock and soil mass according to claim 1, characterized in that A catcher (9) is arranged on the outer side of the transparent confining pressure chamber (3). A CCD camera (6) and a three-dimensional XTDIC full-field strain measuring system (8) are arranged on one side of the catcher (9) away from the transparent confining pressure chamber (3); both the CCD camera (6) and the three-dimensional XTDIC full-field strain measuring system (8) are connected to a computer (10); 7. A seepage-stress coupling visualization device for rock and soil masses according to claim 1, characterized in that The PIV particle image measuring instrument includes a CCD camera (6) and a laser emission light source (7); 8. A test method for a seepage-stress coupling visualization device of rock and soil masses, characterized in that, It includes the following steps: S1, Collect rock / soil mass specimens and make transparent specimens based on the replicated transparent fracture technology and transparent soil technology; S2, Place the transparent specimen inside the transparent confining pressure chamber (3), inject the prepared pore fluid into the water supply device and add a fluorescent agent; S3, Open the seepage inlet and outlet pipeline system (2) to allow the pore fluid to enter the device interior and start the PIV particle image measuring instrument; S4, Adjust the confining pressure control device (4) and the back pressure control device (11) to apply the preset confining pressure and back pressure, and start the axial loading device (5) to apply an axial load to the transparent specimen; S5, use a PIV particle image velocimetry instrument and a three-dimensional XTDIC full-field strain measurement system (8) to record the seepage field and structural evolution.

9. The test method of a seepage-stress coupling visualization device for rock and soil mass according to claim 8, characterized in that, The steps for preparing the transparent specimen are as follows: S11, obtain the structural characteristics of the rock / soil mass, including fracture structure, pore characteristics, mineral composition, and fracture surface properties; S12, fabricate a transparent fractured rock mass specimen and a transparent soil specimen, and combine the transparent soil specimen with the transparent fractured rock mass specimen to form a transparent specimen of the rock / soil mass interface.

10. The test method of a geotechnical seepage-stress coupling visualization device according to claim 8, characterized in that, Use this test method to conduct multi-phase and multi-directional seepage experiments on the rock / soil mass and its interface under triaxial stress conditions, setting the confining pressure at 0 - 20 MPa, the axial displacement at 0 - 20 mm, and the osmotic pressure at 0 - 40 MPa.

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