Shearing-seepage orthogonal coupling loading rock mass structural surface testing device, system and method

Abstract

The invention relates to a shear-seepage orthogonal coupling loading rock mass structural plane testing device, system and method, and the system comprises the shear-seepage orthogonal coupling loading rock mass structural plane testing device which comprises a transparent glass panel located on the front surface of a rock sample; the shearing dislocation unit comprises tangential shearing applying structures which are symmetrically distributed on the upper side and the lower side of the structural plane; the seepage unit is transversely arranged on the structural surface in the tangential shearing direction and is used for applying seepage fluid to the rock sample along the structural surface in the direction perpendicular to the tangential shearing direction; the water stop unit comprises a first water stop structure and a second water stop structure, the first water stop structure is arranged between the rock sample and the transparent glass panel, and the second water stop structure is located between the tangential shear applying structures; the system is used for performing, observing and analyzing the whole test, and the method is realized by means of the system. Compared with the prior art, visualization and sealing performance in the test process are considered, and the interaction relation between a complex stress field and a seepage field is reflected more truly.

Description

Technical Field

[0001] The invention relates to the technical field of civil engineering, in particular to a rock mass structural surface testing device for shear-seepage orthogonal coupling loading. Background Art

[0002] Strong geological tectonic activities and engineering disturbances lead to strong unloading and other internal and external dynamic effects, which cause defects of different scales such as structural planes, joints, and intermittent cracks to develop inside the rock mass. These defects become key internal factors affecting the mechanical behavior and stability of the rock mass. In addition, in extremely heavy rainfall, large-scale hydropower projects, and underground engineering construction, these internal defects become the dominant seepage channels for rainwater and groundwater. Under the combined effects of stress field and seepage field, the shear strength of the rock mass structural plane is significantly reduced, and the rock mass gradually deteriorates, which may have an adverse impact on engineering construction or cause geological disasters such as collapse and landslides. Therefore, studying the shear-seepage coupling characteristics of the rock mass structural plane has important engineering significance and academic value.

[0003] Traditional research on the mechanical properties of structural surfaces has focused on the shear strength and morphological damage degradation of structural surfaces with different roughness and structural surfaces containing filling materials under different normal stresses, normal stiffness, shear rates, etc., and has fully reported the research results on strength indicators and their influencing factors under non-coupled conditions. The relevant test equipment and methods are relatively mature, which has also become an important basis for conducting shear-seepage coupling test research.

[0004] In the experimental study of the shear-seepage coupling characteristics of the structural surface, the sealing and water-stopping problem of the test device is the primary concern. The existing technology is mainly reflected in the two aspects of radiation seepage and through-joint seepage. The radiation seepage test device mainly achieves the sealing effect by wrapping a layer of rubber ring around the joint, and injects water pressure in the rock mass above the joint to achieve the purpose of seepage. This test method destroys the integrity of the rock mass on the upper side of the joint, and is inconsistent with the original seepage conditions of the structural surface, and cannot truly and objectively reflect the shear-seepage coupling characteristics of the structural surface. The through-joint seepage test device mainly achieves sealing by pressing a silicone waterstop, rubber strip or other waterstop material on both sides of the structural surface parallel to the shear direction, and applies a stable water flow along the shear direction to achieve the purpose of seepage. This method has obvious improvements and advantages over joint radiation seepage. However, the effective sealing of the test device leads to the complete wrapping of the rock mass, and it is impossible to effectively observe the deformation and destruction process of the structural surface under the shear-seepage coupling in real time. The test data is relatively limited, and it is impossible to fully reveal the shear-seepage coupling mechanism of the structural surface.

[0005] In addition, in the real working condition where the stress field and the seepage field interact with each other, the stress field and the seepage field borne by the structural surface come from all directions. The complex and changeable stress conditions also make the research on the mechanical properties of the structural surface a hot topic and a difficult point. The existing technology mostly applies a stable seepage field along the shear direction, and there is no experimental research on the structural surface under the three-way orthogonal coupling loading conditions of normal stress, tangential stress, and seepage stress. In summary, the existing technology lacks a visual test device for the rock mass structural surface under the shear-seepage orthogonal coupling loading condition. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a rock structure surface test system and method with shear-seepage orthogonal coupling loading with good visualization and sealing.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] According to a first aspect of the present invention, a rock mass structural surface test device for shear-seepage orthogonal coupling loading is provided, the device comprising:

[0009] The transparent glass panel is located on the front side of the rock sample; the shear dislocation unit includes tangential shear applying structures symmetrically distributed on the upper and lower sides of the structural surface; the seepage unit is arranged transversely along the tangential shear direction of the structural surface, and is used to apply seepage fluid to the rock sample along the structural surface perpendicular to the tangential shear direction; the water-stop unit includes a first water-stop structure and a second water-stop structure, the first water-stop structure is arranged between the rock sample and the transparent glass panel, and the second water-stop structure is located between the tangential shear applying structures.

[0010] As a preferred technical solution, the tangential shear applying structure includes a loading pad located on one side of the rock sample and a compression spring located on the opposite side of the loading base.

[0011] As a preferred technical solution, the seepage unit is located on the back of the rock sample and includes a water inlet communication channel; the water inlet communication channel is provided with a plurality of water inlets distributed at equal intervals.

[0012] As a preferred technical solution, the seepage unit also includes a silicone sealing strip and a water inlet sealing strip baffle matching the water inlet communication channel, and the thickness of the silicone sealing strip is greater than the water inlet sealing strip baffle and the water inlet communication channel.

[0013] As a preferred technical solution, the first water-stop structure includes an elastic water-blocking belt, and the elastic water-blocking belt includes a concave sealing strip and a convex sealing strip; the concave sealing strip is fixedly connected to the loading pad; the convex sealing strip is fixedly connected to the transparent glass panel; the concave sealing strip and the convex sealing strip are movably connected by bite.

[0014] As a preferred technical solution, the shear dislocation device also includes a group of normal shear application structures, and the normal shear application structure includes a loading base pad; the elastic water barrier is provided with a directional drainage outlet near the edge of the loading base pad.

[0015] As a preferred technical solution, the second water-stopping structure includes an elastic sealing strip and a pressing device; the elastic sealing strip is located between the tangential shear application structures and is tightly covered on the left and right sides of the structural surface by the pressing device.

[0016] As a preferred technical solution, the pressing device includes a reaction force support spring, a rotating bearing and a rolling compression rod; the rotating bearing is arranged between the loading pad and the elastic sealing strip on one side of the rock sample, and is composed of a plurality of groups of spherical balls; the reaction force support spring is connected to the elastic sealing strip through the rolling compression rod provided at the end, and the other end is connected to the side plate of the device;

[0017] According to the second aspect of the present invention, there is provided a rock structure surface test system for shear-seepage orthogonal coupling loading, comprising an image observation device, a multifunctional reaction frame, a seepage pressurizing device and an electro-hydraulic servo loading device, the above-mentioned rock structure surface test device for shear-seepage orthogonal coupling loading; the image observation device is operated through the transparent glass panel observation system; the multifunctional reaction frame is connected to the shear dislocation unit; the seepage pressurizing device is connected to the seepage unit; the electro-hydraulic servo loading device is connected to the shear dislocation unit and drives the shear dislocation unit.

[0018] According to a third aspect of the present invention, a rock mass structural surface test method for shear-seepage orthogonal coupling loading is provided. The method is implemented by the above-mentioned rock mass structural surface test system for shear-seepage orthogonal coupling loading, and comprises the following steps:

[0019] S1. Install the rock sample containing the structural surface tightly in the rock mass structural surface test device for shear-seepage orthogonal coupling loading, connect the water inlet pipe to the water inlet, connect the water outlet pipe to the water outlet, and inject the fluid medium of the shear-seepage coupling test into the water inlet pipe;

[0020] S2. Start the test machine, apply the normal load to the target value according to the set loading program, start the shear-seepage coupling test, collect the change data of the outlet flow velocity and flow rate, the normal and tangential load-displacement data, and the cloud map data of the strain field and displacement field during the loading process in real time, and calculate the true shear stress value of the rock mass structure surface under the shear-seepage coupling until the end of the test. The calculation expression is as follows:

[0021]

[0022] Among them, τ represents the true shear stress value of the rock mass structural surface, F0 represents the original test data of the tangential load, k represents the total elastic coefficient of the compression spring, k is a constant, s represents the tangential displacement generated during the loading process, and A represents the tangential load area of ​​the specimen and is a constant value;

[0023] S3. Remove the transparent glass panel and the device side panel, take out the rock samples, and conduct further analysis on the structural surface.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1) Visual observation and structural surface sealing are ensured at the same time. A transparent glass panel is provided on the front of the test device, and a special elastic water-blocking belt is provided between the rock sample and the glass panel. A directional drain port is provided on the elastic water-blocking belt, which ensures the sealing of the test device while achieving visual observation;

[0026] 2) It more realistically shows the working conditions of the interaction between the stress field and the seepage field. Different from the traditional shear dislocation device in which the seepage direction is consistent with the tangential shear direction, the present invention is provided with a seepage transposition on the back of the transposition, so that the seepage fluid penetrates into the rock sample perpendicular to the tangential shear direction, and provides a shear-seepage coupling loading test device that can realize the orthogonality of the tangential, normal and seepage directions, which truly reflects the interaction relationship between the complex stress field and the seepage field;

[0027] 3) Effective sealing is achieved during the shear displacement process. The present invention provides elastic sealing strips on the left and right sides of the structural surface. When the test device performs a shear displacement experiment, the reaction force support spring is forced to squeeze the rolling pressure rod, and the rolling pressure rod presses the rotating bearing. The balls in the rotating bearing are dislocated so that the elastic sealing strip is tightly attached to the structural surface, thereby avoiding the elastic sealing strip from falling off due to shear dislocation and causing the seepage liquid to overflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention is being attempted;

[0029] Figure 2 It is a schematic cross-sectional view of a rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0030] Figure 3 It is a left view of the rock structure surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0031] Figure 4 It is a longitudinal section schematic diagram of the rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0032] Figure 5It is a rear view of the rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0033] Figure 6 A detailed view of the seepage unit of the rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0034] Figure 7 This is a structural diagram of the elastic water-blocking belt of the rock structure surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0035] Figure 8 A detailed view of the rotating bearing of the rock mass structural surface test device for shear-seepage orthogonal coupling loading of the present invention;

[0036] Fig. 9 This is a structural diagram of the rock mass structural surface test system for shear-seepage orthogonal coupling loading of the present invention.

[0037] Reference numerals:

[0038] 1- Image observation system, 2- Multifunctional reaction frame, 3- Rock structure surface test device for shear-seepage orthogonal coupling loading, 4- Normal loading end, 5- Tangential loading end, 6- Tangential loading end, 7- Normal loading base, 8- Seepage pressurization device, 9- Water inlet storage tank, 10- Water inlet flow rate monitoring device, 11- Water inlet pipe, 12- Water outlet pipe, 13- Water outlet storage tank, 14 Electro-hydraulic servo loading device, 15- Computer data acquisition system, 16- Normal loading pad, 17- Loading base pad, 18- Tangential loading pad, 19- Tangential loading pad, 20- Tangential displacement meter, 21- Device side plate, 22- Side panel fixing bolts, 23-elastic water-proof belt, 24-transparent glass panel, 25-fixing bolts, 26-elastic silicone pad, 27-reaction support spring, 28-compression spring, 29-water outlet, 30-rock sample, 31-structural surface, 32-elastic sealing strip, 33-rotating bearing, 34-rolling pressure rod, 35-water inlet sealing strip baffle, 36-water inlet, 37-annular silicone gasket, 38-annular silicone pad, 39-glass pad, 40-silicone sealing strip, 41-water inlet connecting channel, 42-spherical ball, 43-concave sealing strip, 44-convex sealing strip, 45-bolt gasket, 46-waterproof glass glue, 47-small bolt. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0040] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent.

[0041] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation, and may represent the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0042] Embodiment 1:

[0043] The present embodiment provides a rock structure surface test device for shear-seepage orthogonal coupling loading, aiming to solve the technical problem that the prior art cannot accurately and in real time observe the deformation and destruction process of the rock structure surface under the shear-seepage coupling action, and provide a test device that can overcome the conflict between the sealing of the structure surface and visual observation, and realize the real-time quantitative observation of key data such as the strain field, displacement field, and destruction process of the rock structure surface under the shear-seepage coupling loading condition. The test device is suitable for the study of the shear-seepage coupling action mechanism of the structure surface in rock engineering construction and geological disaster prevention and control.

[0044] Combination Figure 1 and Figure 2 The test device includes four device side panels 21, and the device side panels 21 are fixed by side fixing bolts 22 to form a test device frame. The test device specifically includes: a transparent glass panel 24, a shear dislocation unit, a seepage unit and a water stop unit. The detailed structure is as follows:

[0045] 1. Transparent glass panel:

[0046] The transparent glass panel 24 is located on the front side of the rock sample 30 , and the transparent glass panel 24 is tightly fixed to the transfer side panel 21 by fixing bolts 25 .

[0047] In order to avoid damage to the transparent glass panel 24 during the installation process, an annular silicone gasket 37 is provided at the contact point between the head of the fixing bolt 25 and the transparent glass panel 24. Figure 3 As shown, an annular silicone pad 38 is provided between the device side panel 21 and the transparent glass panel 24 .

[0048] Because the transparent glass panel 24 is fixed on the upper and lower device side panels 21, there is a gap between the rock sample 30 and the transparent glass panel. This gap will make it impossible for the rock sample 30 to be placed firmly in the test device during the test. In order to avoid this phenomenon, a glass gasket 39 is provided between the gap between the rock sample 30 and the transparent glass panel 24 for fastening the rock sample 30.

[0049] 2. Shear dislocation unit:

[0050] The shear dislocation unit includes a tangential shear applying structure and a set of normal shear applying structures.

[0051] The tangential shear applying structure includes a tangential loading pad located on one side of the rock sample 30 and a compression spring 28 located on the opposite side of the tangential loading pad, wherein the compression spring 28 is located on the device side plate 21 and connected to the rigid member that compresses the rock sample 20;

[0052] The tangential shear application structure is divided into two groups and is symmetrically distributed on the upper and lower sides of the structural surface 31; wherein the tangential loading pads include a tangential upward loading pad 18 and a tangential downward loading pad 19, and a tangential displacement meter 20 is provided on the tangential loading pads for the convenience of force analysis;

[0053] The normal shear applying structure includes a normal loading pad 16 and a loading base pad 17. An elastic silicone pad is provided between the normal shear applying structure and the rock sample 30 to fix the rock sample 30 to prevent the rock sample 30 from moving in the normal direction during the experiment.

[0054] In order to prevent the rock sample 30 from being significantly displaced during the shear-dislocation process of the test device, elastic silicone pads 26 are placed in the gap between the device side plate 21 and the shear device, that is, at the four corners of the test device.

[0055] 3. Seepage unit:

[0056] The seepage unit is arranged transversely on the structural surface 31 along the tangential shear direction and is located on the back of the rock sample 30, and is used to apply seepage fluid to the rock sample 30. Figure 4The cross-sectional view shown is for the reference object. The seepage direction is along the structural surface 31 from Figure 4 Seepage from the left side to the right side, that is, seepage along the structural surface 31 perpendicular to the tangential shear direction.

[0057] The specific seepage unit includes a water inlet communication channel 41 , a silicone sealing strip 40 matching the water inlet communication channel 41 , and a water inlet sealing strip baffle 35 .

[0058] The water inlet communication channel 41 is provided with a plurality of water inlets 36 distributed at equal intervals, such as Figure 5 As shown, when the test device is working, the seepage liquid penetrates into the structural surface 31 through the water inlet 36 at a certain pressure.

[0059] The thickness of the silicone seal strip 40 is greater than that of the water inlet seal strip baffle 35 and the water inlet communication channel 41. Figure 6 As shown, the seepage unit is tightly mounted on the device side plate 21 by fixing bolts 25 to prevent seepage of seepage liquid due to incomplete sealing when the seepage unit is working. An annular silicone gasket 37 is arranged between the fixing bolts 25 and the water inlet sealing strip baffle 35 to avoid damage to the baffle.

[0060] 4. Water stop unit:

[0061] The water-stop unit includes a first water-stop structure and a second water-stop structure. The detailed structures of the first water-stop structure and the second water-stop structure are explained as follows:

[0062] The first water-stop structure is located between the rock sample 30 and the transparent glass panel 24 and includes an elastic water-blocking strip 23 composed of a concave sealing strip 43 and a convex sealing strip 44. Figure 7 As shown, the concave sealing strip 43 and the convex sealing strip 44 are movably connected by bite;

[0063] The concave sealing strip 43 is fixedly connected to the tangential loading pad by a small bolt 47. In order to avoid damage, a bolt gasket 45 is provided between the small bolt 47 and the concave sealing strip;

[0064] The convex sealing strip 44 and the transparent glass panel 24 are fixedly connected by a waterproof glass glue 46;

[0065] When the test device is subjected to shear dislocation force, since the concave sealing strip 43 and the convex sealing strip 44 are connected by bite, the structure allows the elastic watertight strip 23 to be twisted and deformed to a certain extent when the structural surfaces 31 are dislocated relative to each other, without affecting the watertight effect;

[0066] A directional drainage outlet 29 is provided on the elastic water-blocking strip 23 near the loading base pad 17 , thereby ensuring that water is discharged in a directional manner through the outlet 29 on the lower side when it seeps out from the front of the structural surface 31 .

[0067] The second water-stopping structure is located between the tangential shear applying structures and includes an elastic sealing strip 32 and a pressing device;

[0068] The elastic sealing strip 32 is located between the tangential shear applying structures and is tightly covered on the left and right sides of the structural surface 31 by a pressing device; the pressing device includes a reaction force support spring 27, a rotating bearing 33 and a rolling compression rod 34 having a plurality of spherical balls 42;

[0069] The details of the rotating bearing 33 are as follows Figure 8 As shown, it is arranged between the loading pad located on one side of the rock sample 30 and the elastic sealing strip 32. When the tangential loading pad applies force to the rock sample 30, the tangential loading pad squeezes the rotating bearing 33, and the spherical ball 42 in the rotating bearing 33 is displaced by the force, so that the elastic sealing strip is deformed;

[0070] The reaction force support spring 27 is connected to the elastic sealing strip 32 through a rolling compression rod 34 provided at the end, and the other end is connected to the device side plate 21. When the test device starts working, the reaction force support spring 27 is subjected to force, causing the rolling compression rod 34 to compress the elastic sealing strip 32, so that the elastic sealing strip 32 is displaced and always fits tightly with the structural surface.

[0071] Embodiment 2:

[0072] This embodiment provides a rock mass structural surface test system for shear-seepage orthogonal coupling loading, the structure of which is as follows Fig. 9 As shown, it includes an image observation device 1, a multifunctional reaction frame 2, a shear-seepage orthogonal coupling loading rock structure surface test device 3, a loading end, a normal loading base 7, a seepage pressurizing device 8, a water inlet storage tank 9, a water inlet flow rate monitoring device 10, a water inlet pipe 11, a water outlet pipe 12, a water outlet storage tank 13, an electro-hydraulic servo loading device 14 and a computer data acquisition system 15;

[0073] The image observation device 1 observes the experimental operation through the transparent glass panel 24;

[0074] The multifunctional reaction frame 2 is provided with a loading end and a normal loading base 7, the loading end is placed in the shear dislocation unit of the rock structure surface test device 3 for shear-seepage orthogonal coupling loading and connected with a loading pad, and the normal loading base 7 is connected with the loading base pad 17;

[0075] The seepage liquid is stored in the water inlet tank 9, and the seepage liquid is injected into the seepage unit through the seepage pressurizing device 8 and the water inlet pipe 11, and the seepage liquid flows to the water outlet tank 13 through the water outlet pipe 12;

[0076] The system visually monitors the state of the seepage fluid entering the test device through the water inlet flow rate monitoring device 10, and adjusts the water inlet flow rate according to the specified requirements to achieve the target water pressure;

[0077] The electro-hydraulic servo loading device 14 is connected to the shearing dislocation unit and drives the shearing dislocation unit;

[0078] The computer data acquisition system 15 collects the data generated by the system during the experiment and displays it.

[0079] Among them, the structure of the rock structure surface test device 3 for shear-seepage orthogonal coupling loading is as described in Example 1. Technical personnel in the relevant field can clearly understand that for the convenience and conciseness of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0080] Embodiment 3:

[0081] The above is an introduction to the system embodiment. The following is a method embodiment to further illustrate the solution of the present invention.

[0082] A rock mass structural surface test method for shear-seepage orthogonal coupling loading is implemented by means of the above-mentioned rock mass structural surface test system for shear-seepage orthogonal coupling loading, and comprises the following steps:

[0083] S1. Install the rock sample 30 with the structural surface 31 into the test device, ensure that the surface of the rock sample 30 is in close contact with the loading pad, and ensure that the elastic sealing strip 32 is in close contact with the left and right sides of the structural surface 31;

[0084] S2. Fix the side plates 21 of the device in four directions, up, down, left, and right, by means of the side plate fixing bolts 22 to ensure that the rock sample 30 is tightly wrapped in the test device;

[0085] S3, install the water inlet communication channel 41, the silicone sealing strip 40 and the water inlet sealing strip baffle 35, and fix the water inlet sealing strip baffle 35 to the left and right side plates of the shear box by fixing bolts 25, so that the silicone sealing strip 40 is closely attached to the surface of the rock sample 30;

[0086] S4, install the transparent glass panel 24, put the glass pad 39, press the elastic watertight strip 23 connecting the transparent glass panel 24 and the loading pad, ensure that the concave sealing strip 43 and the convex sealing strip 44 are completely and tightly engaged, and fix the transparent glass panel 24 to the upper and lower side panels of the shear box by fixing bolts 25;

[0087] S5, connecting the water inlet pipe 11 and the water outlet pipe 12, and injecting the fluid medium of the shear-seepage coupling test into the water inlet storage tank 9;

[0088] S6, start the test machine, apply the normal load to the target value according to the set loading program, and officially start the shear-seepage coupling test, and collect the change data of the outlet flow velocity and flow rate, the normal and tangential load-displacement data, and the cloud map data of the strain field and displacement field during the loading process in real time through the computer data acquisition system 15 until the test is completed;

[0089] S7, dismantle the transparent glass panel 24 and the device side panel 21, take out the rock sample 30, and further analyze its shear surface.

[0090] In data processing, the tangential load generated by the compression spring between the loading pad and the shear box side plate needs to be eliminated. Therefore, the true shear stress value of the rock mass structure surface under the shear-seepage coupling should be:

[0091]

[0092] Where: τ represents the true shear stress value of the rock mass structural surface, unit Pa; F0 represents the original test data of the tangential load, unit N; k represents the total elastic coefficient of the compression spring, k is a constant, unit N / m; s represents the tangential displacement generated during the loading process, unit m; A represents the tangential load area of ​​the specimen, A is a constant, unit m 2 .

[0093] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A rock mass structural surface test device for shear-seepage orthogonal coupling loading, characterized in that: The device includes: A transparent glass panel (24) is located on the front side of the rock sample (30); The shear dislocation unit comprises a tangential shear applying structure symmetrically distributed on both sides of the structural surface (31); The seepage unit is arranged transversely on the structural surface (31) along the tangential shear direction, and is used to apply seepage fluid to the rock sample (30) along the structural surface (31) perpendicular to the tangential shear direction; The water-stopping unit comprises a first water-stopping structure and a second water-stopping structure. The first water-stopping structure is arranged between the rock sample (30) and the transparent glass panel (24), and the second water-stopping structure is located between the tangential shear applying structures.

2. A rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 1, characterized in that: The tangential shear applying structure comprises a loading pad located on one side of the rock sample (30) and a compression spring (28) located on the opposite side of the loading base.

3. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 1 is characterized in that: The seepage unit is located on the back side of the rock sample (30), and comprises a water inlet communication channel (41); the water inlet communication channel (41) is provided with a plurality of water inlets (36) distributed at equal intervals.

4. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 3 is characterized in that: The seepage unit further comprises a silicone seal strip (40) and a water inlet seal strip baffle (35) matched with the water inlet communication channel (41), and the thickness of the silicone seal strip (40) is greater than that of the water inlet seal strip baffle (35) and the water inlet communication channel (41).

5. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 1 is characterized in that: The first water-stopping structure comprises an elastic water-blocking strip (23), and the elastic water-blocking strip (23) comprises a concave sealing strip (43) and a convex sealing strip (44); the concave sealing strip (43) is fixedly connected to the loading pad; the convex sealing strip (44) is fixedly connected to the transparent glass panel (24); the concave sealing strip (43) and the convex sealing strip (44) are movably connected by bite.

6. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 5 is characterized in that: The shear dislocation device also includes a group of normal shear application structures, and the normal shear application structure includes a loading base pad (17); the elastic water barrier (23) is provided with a directional drainage outlet (29) near the loading base pad (17).

7. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 1 is characterized in that: The second water-stopping structure comprises an elastic sealing strip (32) and a pressing device; the elastic sealing strip (32) is located between the tangential shear applying structures and is tightly covered on the left and right sides of the structural surface (31) by the pressing device.

8. The rock mass structural surface test device for shear-seepage orthogonal coupling loading according to claim 7 is characterized in that: The pressing device comprises a reaction force support spring (27), a rotating bearing (33) and a rolling compression rod (34); The rotating bearing (33) is arranged between a loading pad located on one side of the rock sample (30) and the elastic sealing strip (32), and is composed of a plurality of groups of spherical balls (42); The reaction force support spring (27) is connected to the elastic sealing strip (32) via a rolling compression rod (34) provided at the end, and the other end is connected to the device side plate (21).

9. A rock mass structural surface test system for shear-seepage orthogonal coupling loading, comprising an image observation device (1), a multifunctional reaction frame (2), a seepage pressurizing device (8) and an electro-hydraulic servo loading device (14), characterized in that: It also comprises a rock mass structural surface test device (3) for shear-seepage orthogonal coupling loading as described in any one of claims 1 to 8; The image observation device (1) operates through the transparent glass panel (24) observation system; The multifunctional reaction frame (2) is connected to the shear dislocation unit; The seepage pressure device (8) is connected to the seepage unit; The electro-hydraulic servo loading device (14) is connected to the shearing dislocation unit and drives the shearing dislocation unit.

10. A rock mass structural surface test method with shear-seepage orthogonal coupling loading, characterized in that: The method is implemented by the rock mass structural surface test system for shear-seepage orthogonal coupling loading as claimed in claim 9, comprising the following steps: S1. tightly install the rock sample (30) containing the structural surface (31) in a rock structural surface test device (3) for shear-seepage orthogonal coupling loading, connect the water inlet pipe (11) to the water inlet (36), connect the water outlet pipe (12) to the water outlet (29), and inject the fluid medium of the shear-seepage coupling test into the water inlet pipe (11); S2, start the test machine, apply the normal load to the target value according to the set loading program, start the shear-seepage coupling test, collect the change data of the flow velocity and flow rate of the outlet (29), the load-displacement data in the normal and tangential directions, and the cloud map data of the strain field and displacement field during the loading process in real time, and calculate the real shear stress value of the rock mass structural surface under the shear-seepage coupling effect until the end of the test. The calculation expression is as follows: Among them, τ represents the true shear stress value of the rock mass structural surface, F0 represents the original test data of the tangential load, k represents the total elastic coefficient of the compression spring, k is a constant, s represents the tangential displacement generated during the loading process, and A represents the tangential load area of ​​the specimen and is a constant value; S3, dismantle the transparent glass panel (24) and the device side panel (21), take out the rock sample (30), and further analyze the structural surface (31).

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