Rock mass dilatancy angle in-situ test method and system under action of real stress

Abstract

The invention provides a rock mass dilatancy angle in-situ test method and system under the action of real stress, and belongs to the technical field of rock mechanics tests.A hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module are installed at the engineering position of a rock mass test piece; the in-situ testing device for the rock mass test piece solves the problem of in-situ testing of the fractured rock mass test piece on the engineering scale, meanwhile, a damage model of the rock mass test piece is obtained by carrying out a damage test under the true triaxial condition, the usability and the damage state of the rock mass test piece are judged and evaluated, and finally, the rock mass test piece is tested. Through differentiated loading of the axial pressure loading module and the lateral pressure loading module, the influence of middle principal stress and principal stress axis rotation on the rock mass dilatancy angle is considered, and through fitting of a relation curve of plastic axial strain and plastic body strain, the rock mass dilatancy angle is obtained. The problem that the nonlinear change of the dilatancy angle at different pressure stages is difficult to consider in a conventional indoor test is solved.

Description

Technical Field

[0001] The invention relates to the technical field of rock mechanics testing, and in particular to an in-situ testing method and system for rock mass dilatancy angle under real stress. Background Art

[0002] As underground engineering advances deeper, the volume expansion caused by large deformation of rock mass under high stress leads to large-volume collapse, which has become a new type of engineering disaster that has occurred frequently in recent years. Under high stress, deep rock mass will produce significant irreversible volume expansion before failure, which is called rock mass expansion phenomenon. The results of a large number of triaxial tests on indoor rock specimens show that when the external force exceeds the peak strength, the volume of the rock specimen does not decrease, but increases significantly, and the growth rate increases with the stress, which will eventually lead to rock expansion failure. The engineering rock mass is in a complex triaxial stress state. After the cavern is excavated, its near-field surrounding rock will experience the rotation of the principal stress axis and the change of stress path. If the original principal stress direction before excavation is parallel to the cave axis, the radial stress will be unloaded quickly after excavation, while the tangential principal stress will increase rapidly. Its shear dilation angle will be affected by the stress path, stress history and stress state. Therefore, studying the expansion characteristics of rock mass during loading is the premise for revealing the deformation and failure mechanism of the loose fracture zone of the surrounding rock and the interaction mechanism between the support structure and the surrounding rock. It is of great significance to reveal the deformation and failure mechanism of rock mass under high stress.

[0003] However, rock mass is composed of geological units with certain primary or secondary joints, fissures or structural surfaces and other discontinuities. It is generally believed that rock mass is equal to complete rock + joints. In the prior art, the process of obtaining the dilatancy angle of rock uses complete rock indoors, and there is still a lack of dilatancy angle test determination methods for in-situ rock mass with cracks on an engineering scale. Secondly, before the test, it is impossible to judge the integrity and damage state of the rock. Finally, during the measurement process, it is also impossible to solve the problem of nonlinear changes in the dilatancy angle under different pressure stages. Summary of the invention

[0004] In order to solve the problems in the above-mentioned prior art, the present invention provides an in-situ testing method and system for rock mass dilatancy angle under real stress. The invention obtains an in-situ testing device for rock mass specimens by installing a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module at the engineering position of the rock mass specimen, thereby solving the in-situ testing problem of rock mass specimens with cracks on an engineering scale. At the same time, a damage model of the rock mass specimen is obtained by conducting a damage test, and the availability and damage state of the rock mass specimen are judged to ensure the reliability of the test data of the rock mass specimen. Finally, through the differentiated loading of the axial pressure loading module and the lateral pressure loading module, the influence of the intermediate principal stress and the rotation of the principal stress axis on the rock mass dilatancy angle is considered. By fitting the relationship curve between the plastic axial strain and the plastic volume strain, the problem of nonlinear change of the dilatancy angle under different pressure stages is solved. To achieve the above-mentioned purpose, the technical scheme is as follows:

[0005] In one aspect, the present invention provides an in-situ testing method for rock mass dilatancy angle under real stress, the method comprising:

[0006] S1. Select the test cave wall in the underground project, and obtain the rock specimen and its location information by manual excavation or mechanical cutting;

[0007] S2. According to the location information of the rock mass specimen, the stress level to be applied by the in-situ test device and the stress cycle path of the in-situ test device are calculated by the Heok-Brown strength criterion;

[0008] S3, according to the rock mass specimen, installing a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module to obtain an in-situ testing device for the rock mass specimen;

[0009] S4, according to the stress level that the in-situ test device needs to apply, a damage test is performed and the test data is input into the damage model for processing to obtain damage information. If the damage information is normal, the next step S5 is performed; if the damage information is an alarm, the test is terminated;

[0010] S5. According to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, a cyclic test is performed by the in-situ testing device of the rock specimen to obtain a pressure data set and a strain data set of the rock specimen;

[0011] S6. According to the pressure data set and the strain data set of the rock mass specimen, the dilatancy angle and the change law of the dilatancy angle under different pressure stages are obtained through the control processing module.

[0012] Optionally, the hydraulic servo module comprises:

[0013] Oil pump unit, used to provide stable loading pressure,

[0014] PLC pressure controller is used to achieve precise control of the loading pressure.

[0015] The pressure regulating device is used to adjust the magnitude of the loading pressure.

[0016] The pressure sensor is used to monitor the change of the loading pressure.

[0017] Pipeline, used for the delivery of hydraulic oil,

[0018] RS485 hub, used for data transmission between the hydraulic servo module and the control processing module.

[0019] Optionally, the lateral pressure loading module comprises:

[0020] The X-direction reaction force frame is used to provide the constraint reaction force in the X direction.

[0021] The Y-direction reaction force frame is used to provide the constraint reaction force in the Y direction.

[0022] Hydraulic pillow, used to simulate the real rock lateral stress conditions,

[0023] The outer rigid pad is used to ensure that the forces of the X-direction reaction frame and the Y-direction reaction frame are evenly applied to the hydraulic pillow.

[0024] The inner rigid pad is used to ensure that the hydraulic pillow applies uniform pressure to the rock specimen.

[0025] Friction reduction device, used to reduce the impact of friction during the test;

[0026] The X-direction reaction frame and the Y-direction reaction frame are both rectangular steel frames, the short sides of the X-direction reaction frame and the short sides of the Y-direction reaction frame are in contact with the hydraulic pillow respectively, and the long sides of the X-direction reaction frame and the long sides of the Y-direction reaction frame are not in contact with the hydraulic pillow. The X-direction reaction frame and the Y-direction reaction frame are stacked and arranged up and down, and the short sides of the X-direction reaction frame and the long sides of the Y-direction reaction frame are staggered at an angle of 90°.

[0027] Optionally, the axial pressure loading module comprises:

[0028] The jack is used to provide the axial pressure required for loading.

[0029] The force transfer column is used to transfer the axial pressure to the leveling ellipsoid.

[0030] The leveling ellipsoid is used to adjust the loading angle and eliminate the eccentric load generated during the loading process.

[0031] The bottom plate is used to disperse the reaction force exerted by the jack on the surrounding rock.

[0032] A pad, used to disperse the reaction force applied by the jack to the rock specimen;

[0033] The bottom plate is arranged on the upper part of the leveling ellipsoid, and the bottom plate contacts the surrounding rock. The leveling ellipsoid comprises a convex ellipsoid and a concave ellipsoid, and the convex ellipsoid and the concave ellipsoid are butted against each other to support rotation in any direction.

[0034] Optionally, the deformation measurement module includes:

[0035] The vertical displacement sensor is used to measure the vertical deformation of the rock specimen.

[0036] The horizontal displacement sensor is used to measure the horizontal deformation of the rock specimen.

[0037] A bracket, used for fixing the vertical displacement sensor and the horizontal displacement sensor,

[0038] The L-shaped fixing seat is used to adjust the position of the horizontal displacement sensor.

[0039] Optionally, in S2, according to the position information of the rock mass specimen, the stress level to be applied by the in-situ test device and the stress cycle path of the in-situ test device are calculated by the Heok-Brown strength criterion, including:

[0040] S21, obtaining the buried depth of the rock mass specimen according to the position information of the rock mass specimen;

[0041] S22, obtaining the initial lateral pressure of the rock mass specimen according to the burial depth of the rock mass specimen;

[0042] S23. According to the initial lateral pressure of the rock specimen, the triaxial peak strength of the rock specimen is calculated by the Heok-Brown strength criterion;

[0043] S24. According to the triaxial peak strength of the rock specimen, the axial pressure applied by the in-situ testing device to the rock specimen is obtained by formula (1).

[0044] (1)

[0045] Where: is the axial pressure applied by the in-situ test device to the rock specimen, is the triaxial peak strength of the rock specimen;

[0046] S25, obtaining a stress level that needs to be applied by the in-situ testing device according to the initial lateral pressure of the rock specimen and the axial pressure applied to the rock specimen by the in-situ testing device;

[0047] S26. According to the initial lateral pressure of the rock specimen and the axial pressure applied by the in-situ test device to the rock specimen, the stress cycle path of the in-situ test device is obtained by formula (2):

[0048] (2)

[0049] Where: is the lateral pressure of the i-th step loading of the in-situ test device, is the initial lateral pressure of the rock specimen, i is the step number, i∈n, n is the total number of steps, n≥5.

[0050] Optionally, the training method of the damage model includes:

[0051] S41, according to the stress level applied to the training rock, a constant initial lateral pressure of the training rock is loaded in the X, Y and Z directions of the training rock by the in-situ testing device of the rock mass specimen and measured to obtain strain data of the training rock;

[0052] S42, repeatedly loading and unloading the initial lateral pressure of the training rock, observing the failure state of the training rock and the characteristic points of the strain curve, and obtaining damage information of the training rock;

[0053] S43, replace the training rock, repeat S41 to S43, and obtain a data set of training rocks;

[0054] S44, obtaining an initialized damage model by setting an initialized reinforcement learning environment;

[0055] S45, inputting the training rock data set into the initialized damage model, and obtaining the parameters of the damage model through the isolation forest learning method;

[0056] S46. Update the parameters of the damage model to the initialized damage model to obtain a damage model.

[0057] Optionally, in S5, according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, a cyclic test is performed by the in-situ testing device of the rock specimen to obtain a pressure data set and a strain data set of the rock specimen, including:

[0058] S51. According to the stress level required to be applied by the in-situ testing device, the in-situ testing device of the rock specimen applies an axial pressure at a rate of 0.1 MPa / s to the stress level required to be applied by the in-situ testing device and keeps it constant, so as to obtain a rock specimen with a constant axial pressure;

[0059] S52, the stress cycle path of the in-situ test device is loaded to the lateral side of the rock specimen with constant axial pressure through the in-situ test device of the rock specimen, and data is collected through the control processing module according to the cycle rule to obtain the lateral pressure and corresponding lateral deformation and axial pressure and corresponding axial deformation of the rock specimen, and the cycle rule is as follows:

[0060] like , then the rock specimen has no yield. , then the rock mass specimen has yielded.

[0061] If the rock mass specimen has no yield, the lateral pressure is unloaded to the predetermined At the same time, the maximum value of the step number i is the total number of steps n, and the cycle unloading and loading is performed.

[0062] If the rock mass specimen yields, the lateral pressure is unloaded and the lateral pressure of the i-th step loading of the in-situ test device is maintained. The minimum value of is always not less than the corresponding lateral pressure value when there is yield during unloading , in subsequent unloading, the pressure is always kept greater than ,At the same time, the maximum value of the step number i is the total number of steps n, and cyclic unloading and loading are performed;

[0063] S53, repeating the previous step S52 for a set number of times, and obtaining a pressure data set and a strain data set of the rock specimen by collecting the lateral pressure and the corresponding lateral deformation and the axial pressure and the corresponding axial deformation of the rock specimen.

[0064] Optionally, in S6, according to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen, the dilatancy angle and the change law of the dilatancy angle under different pressure stages are obtained through the control processing module, including:

[0065] S61, obtaining a deviatoric stress data set of the rock mass specimen by calculating through the control processing module according to the pressure data set of the rock mass specimen;

[0066] S62, obtaining a volume strain data set of the rock mass specimen by calculation through the control processing module according to the strain data set of the rock mass specimen and the deviator stress data set of the rock mass specimen;

[0067] S63, obtaining a plastic strain data set of the rock mass specimen by calculating through the control processing module according to the volume strain data set of the rock mass specimen and the strain data set of the rock mass specimen;

[0068] S64, according to the plastic strain data set of the rock mass specimen, a piecewise smooth curve or function fitting is used to obtain a fitting curve of the relationship between the plastic axial strain and the plastic volume strain;

[0069] S65. According to the fitting curve of the relationship between the plastic axial strain and the plastic volume strain, the pressure stage is finitely discretized, and the dilatancy angle under the corresponding pressure stage is obtained by formula (3):

[0070] (3)

[0071] Where: is the dilatancy angle of the rock specimen, is the plastic axial strain of the rock specimen, is the plastic volume strain of the rock specimen;

[0072] S66. According to the dilatancy angle at the corresponding pressure stage, the pressure stage is changed to obtain the dilatancy angle at different pressure stages and the change law of the dilatancy angle.

[0073] On the other hand, the present invention provides an in-situ testing system for rock mass dilatancy angle under real stress, the system is applied to an in-situ testing method for rock mass dilatancy angle under real stress, the system comprising:

[0074] The first acquisition module is used to select the test cave wall in the underground project, and obtain the rock specimen and the location information of the rock specimen by manual excavation or mechanical cutting;

[0075] The second acquisition module is used to obtain the stress level that needs to be applied by the in-situ test device and the stress cycle path of the in-situ test device according to the position information of the rock mass specimen and the Heok-Brown strength criterion calculation;

[0076] A device installation module is used to install a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module according to the rock mass specimen to obtain an in-situ test device for the rock mass specimen;

[0077] A damage module is used to perform a damage test according to the stress level to be applied by the in-situ test device and input the test data into the damage model for processing to obtain damage information. If the damage information is normal, the data collection module is applied; if the damage information is an alarm, the test is terminated;

[0078] A data collection module is used to perform a cyclic test on the rock specimen through the in-situ testing device according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, so as to obtain a pressure data set and a strain data set of the rock specimen;

[0079] The data processing module is used to obtain the dilatancy angle and the change law of the dilatancy angle under different pressure stages through the control processing module according to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen.

[0080] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects:

[0081] On the one hand, the above scheme obtains an in-situ test device for the rock specimen by installing a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module at the engineering position of the rock specimen, thereby solving the problem of in-situ testing of rock specimens with cracks on an engineering scale. On the other hand, a damage model of the rock specimen is obtained by conducting a damage test, and the availability and damage state of the rock specimen are judged to ensure the reliability of the test data of the rock specimen. On the third hand, through the differentiated loading of the axial pressure loading module and the lateral pressure loading module, the influence of the intermediate principal stress and the rotation of the principal stress axis on the dilatancy angle of the rock mass is considered, and the problem of nonlinear change of the dilatancy angle under different pressure stages is solved by fitting the relationship curve between the plastic axial strain and the plastic volume strain. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0083] Figure 1 It is a flow chart of an embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention;

[0084] Figure 2 Schematic diagram of an in-situ testing device in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0085] Figure 3 Schematic diagram of a hydraulic servo module in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0086] Figure 4 It is a cross-sectional schematic diagram of a lateral pressure loading module in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0087] Figure 5 Schematic diagram of an axial pressure loading module in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0088] Figure 6 Schematic diagram of a leveling ellipsoid in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0089] Figure 7Schematic diagram of a deformation measurement module in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0090] Figure 8 It is a flow chart of obtaining the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device in the embodiment of the in-situ testing method of the rock mass dilatancy angle under the real stress of the present invention;

[0091] Fig. 9 It is a flow chart of a method for training a damage model in an embodiment of an in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0092] Fig.10 It is a flow chart of obtaining a pressure data set and a strain data set of a rock mass specimen in an embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention;

[0093] Fig.11 It is a flow chart of obtaining the dilatancy angle and the change law of the dilatancy angle at different pressure stages in the embodiment of the in-situ testing method of the rock mass dilatancy angle under the real stress of the present invention;

[0094] Fig.12 is a curve diagram of the change of deviator stress and lateral stress with time in an embodiment of the in-situ testing method for rock mass dilatancy angle under the action of real stress of the present invention;

[0095] Fig.13 is a curve diagram of the relationship between axial strain, lateral strain and deviator stress in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0096] Fig.14 is a curve diagram of the relationship between axial strain and volume strain in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0097] Fig.15 is a curve diagram of the relationship between plastic axial strain and plastic volume strain in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention;

[0098] Fig.16 It is a system block diagram of an embodiment of the in-situ testing system for rock mass dilatancy angle under real stress of the present invention.

[0099] Explanation of the numbers in the figure: hydraulic servo module 1, lateral pressure loading module 2, axial pressure loading module 3, deformation measurement module 4, control processing module 5, rock specimen 6, surrounding rock 7, oil pump unit 101, PLC pressure controller 102, pressure control device 103, pressure sensor 104, pipeline 105, RS485 hub 106, X-direction reaction frame 201, Y-direction reaction frame 202, hydraulic pillow 203, outer rigid pad 204, inner rigid pad 205, friction reduction device 206, jack 301, force transmission column 302, leveling ellipsoid 303, bottom plate 304, pad 305, convex ellipsoid 3031, concave ellipsoid 3032, vertical displacement sensor 401, horizontal displacement sensor 402, bracket 403, L-shaped fixing seat 404. DETAILED DESCRIPTION

[0100] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0101] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0102] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0103] like Figure 1 The flowchart of the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown in FIG. Figure 2 The schematic diagram of the in-situ testing device in the embodiment of the in-situ testing method of rock mass dilatancy angle under the action of real stress of the present invention is shown. The present invention provides an in-situ testing method of rock mass dilatancy angle under the action of real stress. The method is implemented by an in-situ testing system of rock mass dilatancy angle under the action of real stress. The method comprises:

[0104] S1. Select a test cave wall in an underground project and obtain a rock specimen 6 and its location information by artificial digging or mechanical cutting;

[0105] Specifically, the length and width of the rock specimen 6 are equal, the side length is not less than 30 cm, the height is twice the length, the bottom surface of the rock specimen 6 is connected to the surrounding rock 7, and the side and top surfaces of the rock specimen 6 need to be polished and smooth.

[0106] S2. According to the position information of the rock mass specimen 6, the stress level to be applied by the in-situ test device and the stress cycle path of the in-situ test device are calculated by the Heok-Brown strength criterion;

[0107] Specifically, Figure 8 The flowchart of obtaining the stress level required to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device in the embodiment of the in-situ testing method of the rock mass dilatancy angle under the real stress of the present invention shown in S2 is obtained by calculating the stress level required to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device according to the position information of the rock mass specimen 6 by the Heok-Brown strength criterion, including:

[0108] S21, obtaining the buried depth of the rock mass specimen 6 according to the position information of the rock mass specimen 6;

[0109] S22, obtaining the initial lateral pressure of the rock mass specimen 6 according to the buried depth of the rock mass specimen 6;

[0110] S23, according to the initial lateral pressure of the rock specimen 6, the triaxial peak strength of the rock specimen 6 is calculated by the Heok-Brown strength criterion;

[0111] S24. According to the triaxial peak strength of the rock specimen 6, the axial pressure applied by the in-situ testing device to the rock specimen 6 is obtained by formula (1).

[0112] (1)

[0113] Where: is the axial pressure applied by the in-situ test device to the rock specimen, is the triaxial peak strength of the rock specimen;

[0114] S25, obtaining a stress level that needs to be applied by the in-situ testing device according to the initial lateral pressure of the rock specimen 6 and the axial pressure applied to the rock specimen 6 by the in-situ testing device;

[0115] S26. According to the initial lateral pressure of the rock specimen 6 and the axial pressure applied by the in-situ testing device to the rock specimen 6, the stress cycle path of the in-situ testing device is obtained by formula (2):

[0116] (2)

[0117] Where: is the lateral pressure of the i-th step loading of the in-situ test device, is the initial lateral pressure of the rock specimen, i is the step number, i∈n, n is the total number of steps, n≥5.

[0118] S3, according to the rock specimen 6, installing the hydraulic servo module 1, the lateral pressure loading module 2, the axial pressure loading module 3, the deformation measurement module 4 and the control processing module 5 to obtain an in-situ testing device for the rock specimen;

[0119] Specifically, Figure 3 The schematic diagram of the hydraulic servo module in the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown, and the hydraulic servo module 1 includes:

[0120] The oil pump unit 101 is used to provide a stable loading pressure.

[0121] The PLC pressure controller 102 is used to achieve precise control of the loading pressure.

[0122] The pressure regulating device 103 is used to adjust the magnitude of the loading pressure.

[0123] The pressure sensor 104 is used to monitor the change of the loading pressure.

[0124] Pipeline 105 is used for the delivery of hydraulic oil.

[0125] RS485 hub 106, used for data transmission between the hydraulic servo module 1 and the control processing module 5;

[0126] Furthermore, the oil pump unit 101 is composed of three independent motors and oil pumps, which provide stable loading pressure in the X, Y and Z directions respectively;

[0127] The PLC pressure controller 102 receives the pressure instruction of the control processing module 5 through the RS485 hub 106, and sends a pressure adjustment instruction to the pressure control device 103;

[0128] The pressure regulating device 103 is installed at the output end of the oil pump unit 101, and regulates the output pressure of the oil pump unit 101 according to the received pressure regulating instruction;

[0129] The pressure sensor 104 is installed at the front end of the pipeline 105 to monitor the pressure change of the pipeline 105 in real time and send it to the pressure control device 103;

[0130] The pipeline 105 connects the hydraulic servo module 1 with the lateral pressure loading module 2 and the axial pressure loading module 3 .

[0131] Specifically, Figure 4 The cross-sectional schematic diagram of the lateral pressure loading module in the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown, and the lateral pressure loading module 2 includes:

[0132] The X-direction reaction force frame 201 is used to provide the constraint reaction force in the X-direction.

[0133] The Y-direction reaction force frame 202 is used to provide the constraint reaction force in the Y direction.

[0134] Hydraulic pillow 203, used to simulate the real rock lateral stress conditions,

[0135] The outer rigid pad 204 is used to ensure that the forces of the X-direction reaction frame 201 and the Y-direction reaction frame 202 are uniformly applied to the hydraulic pillow.

[0136] The inner rigid pad 205 is used to ensure that the hydraulic pillow 203 applies uniform pressure to the rock specimen 6.

[0137] A friction reducing device 206 is used to reduce the effect of friction during the test;

[0138] Further, the X-direction reaction force frame 201 and the Y-direction reaction force frame 202 provide reaction forces for the hydraulic pillow 203 in the X-direction and the Y-direction respectively;

[0139] The X-direction reaction frame 201 and the Y-direction reaction frame 202 are both rectangular steel frames, the short sides of the X-direction reaction frame 201 and the short sides of the Y-direction reaction frame 202 are in contact with the hydraulic pillow 203 respectively, and the long sides of the X-direction reaction frame 201 and the long sides of the Y-direction reaction frame 202 are not in contact with the hydraulic pillow 203, the X-direction reaction frame 201 and the Y-direction reaction frame 202 are stacked and arranged up and down, and the short sides of the X-direction reaction frame 201 and the long sides of the Y-direction reaction frame 202 are staggered at an angle of 90°;

[0140] The friction reducing device 206 is formed by overlapping two plastic plates with lubricating oil applied in the middle, and is used to reduce the friction between the hydraulic pillow 203 and the rock sample 6.

[0141] Specifically, Figure 5 The schematic diagram of the axial pressure loading module in the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown, and the axial pressure loading module 3 includes:

[0142] Jack 301 is used to provide the axial pressure required for loading.

[0143] The force transmission column 302 is used to transmit the axial pressure to the leveling ellipsoid 303.

[0144] The leveling ellipsoid 303 is used to adjust the loading angle and eliminate the eccentric load generated during the loading process.

[0145] The bottom plate 304 is used to disperse the reaction force exerted by the jack 301 on the surrounding rock 7.

[0146] A pad 305, used to disperse the reaction force applied by the jack 301 to the rock specimen 6;

[0147] Furthermore, the lower end of the jack 301 is connected to the rock specimen 6 through the pad 305, and the force transmission column 302 is arranged at the upper end;

[0148] like Figure 6 The schematic diagram of the leveling ellipsoid in the embodiment of the in-situ testing method of rock shear dilatancy angle under the real stress of the present invention is shown, the base plate 304 is arranged on the upper part of the leveling ellipsoid 303, and the base plate 304 is in contact with the surrounding rock 7. The leveling ellipsoid 303 includes a convex ellipsoid 3031 and a concave ellipsoid 3032, and the convex ellipsoid 3031 and the concave ellipsoid 3032 are connected to each other to support rotation in any direction.

[0149] Specifically, Figure 7 The schematic diagram of the deformation measurement module in the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown, and the deformation measurement module 4 includes:

[0150] The vertical displacement sensor 401 is used to measure the vertical deformation of the rock specimen 6.

[0151] The horizontal displacement sensor 402 is used to measure the horizontal deformation of the rock specimen 6.

[0152] The bracket 403 is used to fix the vertical displacement sensor 401 and the horizontal displacement sensor 402.

[0153] An L-shaped fixing seat 404 is used to adjust the position of the horizontal displacement sensor 402;

[0154] Furthermore, the vertical displacement sensor 401 and the horizontal displacement sensor 402 are connected to the bracket 403 via the L-shaped fixing seat 404; the end of the bottom surface of the L-shaped fixing seat 404 is connected to the bracket 403 via screws;

[0155] The horizontal displacement sensor 402 is arranged at the center of the four sides of the rock sample 6, and the vertical displacement sensor 401 is arranged symmetrically on both sides of the upper end of the rock sample 6.

[0156] The vertical displacement sensor 401 and the horizontal displacement sensor 402 are connected to the RS485 hub 106 , and the data of the vertical displacement sensor 401 and the data of the horizontal displacement sensor 402 are transmitted to the control processing module 5 through the RS485 hub 106 .

[0157] S4, according to the stress level that the in-situ test device needs to apply, a damage test is performed and the test data is input into the damage model for processing to obtain damage information. If the damage information is normal, the next step S5 is performed; if the damage information is an alarm, the test is terminated;

[0158] Specifically, Fig. 9 The flowchart of the damage model training method in the embodiment of the in-situ testing method of rock mass dilatancy angle under real stress of the present invention is shown, and the damage model training method comprises:

[0159] S41, according to the stress level applied to the training rock, a constant initial lateral pressure of the training rock is loaded in the X, Y and Z directions of the training rock by the in-situ testing device of the rock mass specimen and measured to obtain strain data of the training rock;

[0160] S42, repeatedly loading and unloading the initial lateral pressure of the training rock, observing the failure state of the training rock and the characteristic points of the strain curve, and obtaining damage information of the training rock;

[0161] S43, replace the training rock, repeat S41 to S43, and obtain a data set of training rocks;

[0162] S44, obtaining an initialized damage model by setting an initialized reinforcement learning environment;

[0163] S45, inputting the training rock data set into the initialized damage model, and obtaining the parameters of the damage model through the isolation forest learning method;

[0164] S46. Update the parameters of the damage model to the initialized damage model to obtain a damage model.

[0165] S5. According to the stress level of the in-situ testing device and the stress cycle path of the in-situ testing device, a cyclic test is performed through the in-situ testing device of the rock specimen to obtain a pressure data set and a strain data set of the rock specimen;

[0166] Specifically, Fig.10 The flowchart of obtaining a pressure data set and a strain data set of a rock specimen in the embodiment of the in-situ testing method for rock mass dilatancy angle under the action of real stress of the present invention is shown, and S5 performs a cyclic test through the in-situ testing device of the rock specimen 6 according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device to obtain the pressure data set and the strain data set of the rock specimen 6, including:

[0167] S51, according to the stress level that needs to be applied by the in-situ testing device, the in-situ testing device of the rock specimen 6 applies an axial pressure to the stress level that needs to be applied by the in-situ testing device at a rate of 0.1 MPa / s and keeps it constant, to obtain a rock specimen with a constant axial pressure;

[0168] S52, the stress cycle path to be applied by the in-situ test device is loaded to the lateral side of the rock specimen 6 with constant axial pressure through the in-situ test device of the rock specimen 6, and data is collected through the control processing module according to the cycle rule to obtain the lateral pressure and the corresponding lateral deformation and the axial pressure and the corresponding axial deformation of the rock specimen 6. The cycle rule is as follows:

[0169] like , then the rock specimen 6 has no yield. , then the rock specimen 6 has yielded,

[0170] If the rock mass specimen 6 does not yield, the lateral pressure is unloaded to the predetermined At the same time, the maximum value of the step number i is the total number of steps n, and the cycle unloading and loading is performed.

[0171] If the rock specimen 6 yields, the lateral pressure is unloaded and the lateral pressure of the i-th step loading of the in-situ test device is maintained. The minimum value of is always not less than the corresponding lateral pressure value when there is yield during unloading , in subsequent unloading, the pressure is always kept greater than ,At the same time, the maximum value of the step number i is the total number of steps n, and cyclic unloading and loading are performed;

[0172] S53, repeating the previous step S52 for a set number of times, and obtaining a pressure data set and a strain data set of the rock specimen 6 by collecting the lateral pressure and the corresponding lateral deformation and the axial pressure and the corresponding axial deformation of the rock specimen 6.

[0173] S6. According to the pressure data set of the rock mass specimen 6 and the strain data set of the rock mass specimen 6, the dilatancy angle and the change law of the dilatancy angle under different pressure stages are obtained through the control processing module.

[0174] Specifically, Fig.11 The flowchart of obtaining the dilatancy angle and the change law of the dilatancy angle at different pressure stages in the embodiment of the in-situ testing method of the rock mass dilatancy angle under the real stress of the present invention is shown, and S6 obtains the dilatancy angle and the change law of the dilatancy angle at different pressure stages through the control processing module according to the pressure data set of the rock mass specimen 6 and the strain data set of the rock mass specimen 6, including:

[0175] S61, according to the pressure data set of the rock mass specimen 6, the control processing module calculates and obtains the deviator stress data set of the rock mass specimen 6;

[0176] Furthermore, the deviatoric stress calculation method is shown in formula (4):

[0177] (4)

[0178] Where: is the deviatoric stress, is the axial stress, is the lateral stress;

[0179] like Fig.12 As shown in the curve diagram of the deviator stress and lateral stress changing with time in the embodiment of the in-situ testing method for rock mass dilatancy angle under the real stress of the present invention, the control processing module draws the curve diagram of the deviator stress and lateral stress changing with time.

[0180] S62, obtaining a volume strain data set of the rock mass specimen 6 by calculating through the control processing module according to the strain data set of the rock mass specimen 6 and the deviator stress data set of the rock mass specimen 6;

[0181] Furthermore, if Fig.13 The curve diagram of the relationship between the axial strain, the lateral strain and the deviator stress in the embodiment of the in-situ testing method of the rock mass dilatancy angle under the real stress of the present invention is shown, and the control processing module draws the curve diagram of the relationship between the axial strain, the lateral strain and the deviator stress;

[0182] The calculation method of volume strain is shown in formula (5):

[0183] (5)

[0184] Where: is the total axial strain, is the total lateral strain in the X direction, is the total lateral strain in the Y direction, is the body strain;

[0185] like Fig.14 As shown is a curve diagram of the relationship between axial strain and volume strain in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention, the control processing module draws a curve diagram of the relationship between axial strain and volume strain.

[0186] S63, obtaining a plastic strain data set of the rock mass specimen 6 by calculating through the control processing module according to the volume strain data set of the rock mass specimen 6 and the strain data set of the rock mass specimen 6;

[0187] Furthermore, according to the characteristics of irreversible strain increment, in the in-situ test of rock dilatancy angle under real stress, the irreversible strain at the end of each cycle is the plastic strain corresponding to the cycle.

[0188] S64, according to the plastic strain data set of the rock mass specimen 6, a piecewise smooth curve or function fitting is used to obtain a fitting curve of the relationship between the plastic axial strain and the plastic volume strain;

[0189] Furthermore, if Fig.15 As shown is a curve diagram of the relationship between plastic axial strain and plastic volume strain in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention, the plastic strain can be obtained based on the curve diagram of the relationship between axial strain and volume strain.

[0190] S65. According to the fitting curve of the relationship between the plastic axial strain and the plastic volume strain, the pressure stage is finitely discretized, and the dilatancy angle under the corresponding pressure stage is obtained by formula (3):

[0191] (3)

[0192] Where: is the dilatancy angle of the rock specimen, is the plastic axial strain of the rock specimen, is the plastic volume strain of the rock specimen;

[0193] Furthermore, if Fig.15 As shown is a curve diagram of the relationship between plastic axial strain and plastic volume strain in an embodiment of the in-situ testing method for rock mass dilatancy angle under real stress of the present invention, the control processing module draws a curve diagram of the relationship between plastic axial strain and plastic volume strain.

[0194] S66. According to the dilatancy angle at the corresponding pressure stage, the pressure stage is changed to obtain the dilatancy angle at different pressure stages and the change law of the dilatancy angle.

[0195] like Fig.16 The system block diagram of the embodiment of the in-situ testing system of rock mass dilatancy angle under real stress of the present invention is shown. The present invention provides an in-situ testing system of rock mass dilatancy angle under real stress. The system is applied to an in-situ testing method of rock mass dilatancy angle under real stress. The system includes a first acquisition module, a second acquisition module, a device installation module, a damage module, a data collection module and a data processing module. Specifically,

[0196] The first acquisition module is used to select the test cave wall in the underground project, and obtain the rock specimen and the location information of the rock specimen by manual excavation or mechanical cutting;

[0197] The second acquisition module is used to obtain the stress level that needs to be applied by the in-situ test device and the stress cycle path of the in-situ test device according to the position information of the rock mass specimen and the Heok-Brown strength criterion calculation;

[0198] A device installation module is used to install a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module according to the rock mass specimen to obtain an in-situ test device for the rock mass specimen;

[0199] A damage module is used to perform a damage test according to the stress level to be applied by the in-situ test device and input the test data into the damage model for processing to obtain damage information. If the damage information is normal, the data collection module is applied; if the damage information is an alarm, the test is terminated;

[0200] A data collection module is used to perform a cyclic test on the rock specimen through the in-situ testing device according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, so as to obtain a pressure data set and a strain data set of the rock specimen;

[0201] The data processing module is used to obtain the dilatancy angle and the change law of the dilatancy angle under different pressure stages through the control processing module according to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen.

[0202] The present invention provides an in-situ testing method and system for rock mass dilatancy angle under real stress. The invention obtains an in-situ testing device for rock mass specimens by installing a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module at the engineering position of the rock mass specimen, thereby solving the in-situ testing problem of rock mass specimens with cracks on an engineering scale. At the same time, a damage model of the rock mass specimen is obtained by conducting a damage test, and the availability and damage state of the rock mass specimen are judged to ensure the reliability of the test data of the rock mass specimen. Finally, through the differentiated loading of the axial pressure loading module and the lateral pressure loading module, the influence of the intermediate principal stress and the rotation of the principal stress axis on the rock mass dilatancy angle is considered, and the problem of nonlinear change of the dilatancy angle under different pressure stages is solved by fitting the relationship curve between the plastic axial strain and the plastic volume strain.

[0203] It is to be understood that the present invention is described by the above embodiments and should not be construed as limiting the embodiments of the present invention and the scope of the present invention. It is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. An in-situ testing method for rock mass dilatancy angle under real stress, characterized in that: The method comprises: S1. Select the test cave wall in the underground project, and obtain the rock specimen and its location information by manual excavation or mechanical cutting; S2. According to the position information of the rock mass specimen, the stress level to be applied by the in-situ test device and the stress cycle path of the in-situ test device are calculated by the Heok-Brown strength criterion; S3, according to the rock mass specimen, installing a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module to obtain an in-situ testing device for the rock mass specimen; S4, according to the stress level that the in-situ test device needs to apply, a damage test is performed and the test data is input into the damage model for processing to obtain damage information. If the damage information is normal, the next step S5 is performed; if the damage information is an alarm, the test is terminated; S5. According to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, a cyclic test is performed by the in-situ testing device of the rock specimen to obtain a pressure data set and a strain data set of the rock specimen; S6. According to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen, the dilatancy angle and the change law of the dilatancy angle under different pressure stages are obtained through the control processing module.

2. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1, characterized in that: The hydraulic servo module comprises: Oil pump unit, used to provide stable loading pressure, PLC pressure controller, used to achieve precise control of the loading pressure, A pressure regulating device is used to adjust the magnitude of the loading pressure. A pressure sensor for monitoring changes in the loading pressure, Pipeline for the delivery of hydraulic oil, RS485 hub, used for data transmission between the hydraulic servo module and the control processing module.

3. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1, characterized in that: The lateral pressure loading module comprises: The X-direction reaction force frame is used to provide the constraint reaction force in the X direction. The Y-direction reaction force frame is used to provide the constraint reaction force in the Y direction. Hydraulic pillow, used to simulate the real rock lateral stress conditions, The outer rigid pad is used to ensure that the forces of the X-direction reaction frame and the Y-direction reaction frame are evenly applied to the hydraulic pillow. The inner rigid pad is used to ensure that the hydraulic pillow applies uniform pressure to the rock specimen. Friction reduction device, used to reduce the impact of friction during the test; The X-direction reaction frame and the Y-direction reaction frame are both rectangular steel frames, the short sides of the X-direction reaction frame and the short sides of the Y-direction reaction frame are in contact with the hydraulic pillow respectively, and the long sides of the X-direction reaction frame and the long sides of the Y-direction reaction frame are not in contact with the hydraulic pillow, the X-direction reaction frame and the Y-direction reaction frame are stacked and arranged up and down, and the short sides of the X-direction reaction frame and the long sides of the Y-direction reaction frame are staggered at an angle of 90°.

4. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1 is characterized in that: The axial pressure loading module comprises: The jack is used to provide the axial pressure required for loading. The force transmission column is used to transmit the axial pressure to the leveling ellipsoid. The leveling ellipsoid is used to adjust the loading angle and eliminate the eccentric load generated during the loading process. The bottom plate is used to disperse the reaction force exerted by the jack on the surrounding rock. A pad, used to disperse the reaction force applied by the jack to the rock specimen; The bottom plate is arranged on the upper part of the leveling ellipsoid, and the bottom plate is in contact with the surrounding rock. The leveling ellipsoid comprises a convex ellipsoid and a concave ellipsoid, and the convex ellipsoid and the concave ellipsoid are connected to support rotation in any direction.

5. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1, characterized in that: The deformation measurement module comprises: A vertical displacement sensor is used to measure the vertical deformation of the rock specimen. The horizontal displacement sensor is used to measure the horizontal deformation of the rock specimen. A bracket, used to fix the vertical displacement sensor and the horizontal displacement sensor, The L-shaped fixing seat is used to adjust the position of the horizontal displacement sensor.

6. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1, characterized in that: In S2, according to the position information of the rock mass specimen, the stress level to be applied by the in-situ test device and the stress cycle path of the in-situ test device are calculated by the Heok-Brown strength criterion, including: S21, obtaining the buried depth of the rock mass specimen according to the position information of the rock mass specimen; S22, obtaining an initial lateral pressure of the rock mass specimen according to the burial depth of the rock mass specimen; S23. According to the initial lateral pressure of the rock specimen, the triaxial peak strength of the rock specimen is calculated by the Heok-Brown strength criterion; S24. According to the triaxial peak strength of the rock specimen, the axial pressure applied by the in-situ testing device to the rock specimen is obtained by formula (1). （1） Where: is the axial pressure applied by the in-situ test device to the rock specimen, is the triaxial peak strength of the rock specimen; S25, obtaining a stress level that needs to be applied by the in-situ testing device according to the initial lateral pressure of the rock specimen and the axial pressure applied by the in-situ testing device to the rock specimen; S26. According to the initial lateral pressure of the rock specimen and the axial pressure applied by the in-situ testing device to the rock specimen, the stress cycle path of the in-situ testing device is obtained by formula (2): （2） Where: is the lateral pressure of the i-th step loading of the in-situ test device, is the initial lateral pressure of the rock specimen, i is the step number, i∈n, n is the total number of steps, n≥5.

7. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 1, characterized in that: The damage model training method comprises: S41, according to the stress level applied to the training rock, a constant initial lateral pressure of the training rock is loaded in the X, Y and Z directions of the training rock by the in-situ testing device of the rock mass specimen and measured to obtain strain data of the training rock; S42, repeatedly loading and unloading the initial lateral pressure of the training rock, observing the failure state of the training rock and the characteristic points of the strain curve, and obtaining damage information of the training rock; S43, replace the training rock, repeat S41 to S43, and obtain a data set of training rocks; S44, obtaining an initialized damage model by setting an initialized reinforcement learning environment; S45, inputting the training rock data set into the initialized damage model, and obtaining the parameters of the damage model through the isolation forest learning method; S46. Update the parameters of the damage model to the initialized damage model to obtain a damage model.

8. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 6, characterized in that: In S5, according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, a cyclic test is performed by the in-situ testing device of the rock specimen to obtain a pressure data set and a strain data set of the rock specimen, including: S51. According to the stress level required to be applied by the in-situ testing device, the in-situ testing device of the rock specimen applies an axial pressure to the stress level required to be applied by the in-situ testing device at a rate of 0.1 MPa / s and keeps it constant, so as to obtain a rock specimen with a constant axial pressure; S52, the stress cycle path of the in-situ test device is loaded to the lateral side of the rock specimen with constant axial pressure through the in-situ test device of the rock specimen, and data is collected through the control processing module according to the cycle rule to obtain the lateral pressure and corresponding lateral deformation and axial pressure and corresponding axial deformation of the rock specimen, and the cycle rule is as follows: like , then the rock specimen has no yield. , then the rock mass specimen has yielded, If the rock mass specimen does not yield, the lateral pressure is unloaded to the predetermined At the same time, the maximum value of the step number i is the total number of steps n, and the cycle unloading and loading is performed. If the rock mass specimen yields, the lateral pressure is unloaded and the lateral pressure of the i-th step loading of the in-situ test device is maintained. The minimum value of is always not less than the corresponding lateral pressure value when there is yield during unloading , in subsequent unloading, the pressure is always kept greater than ,At the same time, the maximum value of the step number i is the total number of steps n, and cyclic unloading and loading are performed; S53, repeating the previous step S52 for a set number of times, and obtaining a pressure data set and a strain data set of the rock specimen by collecting the lateral pressure and the corresponding lateral deformation and the axial pressure and the corresponding axial deformation of the rock specimen.

9. The in-situ testing method for rock mass dilatancy angle under real stress according to claim 8, characterized in that: In S6, according to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen, the dilatancy angle and the change law of the dilatancy angle under different pressure stages are obtained through the control processing module, including: S61, obtaining a deviatoric stress data set of the rock mass specimen by calculating through the control processing module according to the pressure data set of the rock mass specimen; S62, obtaining a volume strain data set of the rock mass specimen by calculation through the control processing module according to the strain data set of the rock mass specimen and the deviator stress data set of the rock mass specimen; S63, obtaining a plastic strain data set of the rock mass specimen by calculating through the control processing module according to the volume strain data set of the rock mass specimen and the strain data set of the rock mass specimen; S64, according to the plastic strain data set of the rock mass specimen, using piecewise smooth curve or function fitting to obtain a fitting curve of the relationship between the plastic axial strain and the plastic volume strain; S65, according to the relationship fitting curve between the plastic axial strain and the plastic volume strain, the pressure stage is finitely discretized, and the dilatancy angle under the corresponding pressure stage is obtained by formula (3), （3） Where: is the dilatancy angle of the rock specimen, is the plastic axial strain of the rock specimen, is the plastic volume strain of the rock specimen; S66. According to the dilatancy angle at the corresponding pressure stage, the pressure stage is changed to obtain the dilatancy angle at different pressure stages and the change law of the dilatancy angle.

10. An in-situ testing system for rock mass dilatancy angle under real stress, used to implement the in-situ testing method for rock mass dilatancy angle under real stress as claimed in any one of claims 1 to 9, characterized in that: The system comprises: The first acquisition module is used to select the test cave wall in the underground project, and obtain the rock specimen and the location information of the rock specimen by manual excavation or mechanical cutting; A second acquisition module is used to obtain the stress level that needs to be applied by the in-situ test device and the stress cycle path of the in-situ test device according to the position information of the rock mass specimen and the Heok-Brown strength criterion calculation; A device installation module is used to install a hydraulic servo module, a lateral pressure loading module, an axial pressure loading module, a deformation measurement module and a control processing module according to the rock specimen to obtain an in-situ test device for the rock specimen; A damage module is used to perform a damage test according to the stress level to be applied by the in-situ test device and input the test data into the damage model for processing to obtain damage information. If the damage information is normal, a data collection module is applied; if the damage information is an alarm, the test is terminated; a data collection module, configured to perform a cyclic test on the rock specimen through the in-situ testing device according to the stress level to be applied by the in-situ testing device and the stress cycle path of the in-situ testing device, so as to obtain a pressure data set and a strain data set of the rock specimen; The data processing module is used to obtain the dilatancy angle and the change law of the dilatancy angle under different pressure stages through the control processing module according to the pressure data set of the rock mass specimen and the strain data set of the rock mass specimen.

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