Method for simulating fracture development and fragmentation process of fractured rock mass and simulation device

Abstract

The invention particularly relates to a method for simulating the fracture development and fragmentation process of fractured rock mass and a simulation device, and belongs to the technical field of rock fracture simulation. The method comprises the following steps: S1, preparing cement mortar with proper strength, and putting the cement mortar into a cubic mold; s2, after initial setting of the cement mortar, a crack combination is arranged on the pressed face of the cement mortar block to form a sample, a first reference axis and a second reference axis which are perpendicular are arranged on the face of the cement mortar block, the crack combination comprises a first crack group and a second crack group, two cracks of the first crack group are arranged on the two sides of the first reference axis, and two cracks of the second crack group are arranged on the two sides of the second reference axis; the included angles between the first reference axis and the second reference axis are # imgabs 0 # and # imgabs 1 # respectively. The second fissure group is arranged on the two sides of the second reference axis respectively, the included angles between the second fissure group and the second reference axis are # imgabs2 # and # imgabs3 # respectively, and the middle parts of all fissures intersect at the midpoint of the plane. And S3, cyclic stress loading is carried out on the pressed surface. And S4, adjusting the magnitude of the loaded stress, and then circularly loading the stress until the sample is broken.

Description

Technical Field

[0001] The invention belongs to the technical field of rock fracture simulation, and in particular relates to a method and a simulation device for simulating the fracture development and fragmentation process of a fractured rock mass. Background Art

[0002] The failure mechanism and crack extension mechanism of fractured rock mass are important research topics in the field of geotechnical engineering. The instability of many rock mass projects is related to the extension and penetration of cracks in the rock mass. Numerous rock mass engineering practices and a large number of experimental studies at home and abroad have shown that the instability and destruction of rock mass projects are mostly caused by the evolution, extension and penetration of the original joint surface under the action of changes in the stress environment. For example, the instability of the Mipasse Dam in France was caused by the extension of microcracks in the gneiss of the dam foundation. Accidents such as the slope slip in Vaion, Italy, and the landslide in the Fengjie section of the Three Gorges Dam on the Yangtze River in China are all related to the extension of their own cracks. In short, the development and evolution laws of fractured rock mass and the fragmentation process of jointed rock mass are crucial to the stability of the rock mass.

[0003] Conjugate joints are a common structural phenomenon in rock mass. Conjugate joints refer to two or more groups of nearly vertical and intersecting joints (or cracks). These joints usually have similar causes and characteristics, but their strike and inclination are perpendicular or nearly perpendicular to each other, forming a unique "X" shape or "conjugate" relationship. When current technology simulates the development of rock mass cracks, it mostly uses samples with smooth surfaces. There is a lack of simulation process for samples with conjugate joints, which reduces the degree of simulation and may lead to errors in the research results. Summary of the invention

[0004] The purpose of the present invention is to provide a method and a simulation device for simulating the crack development and fragmentation process of a fractured rock mass, by which the development of conjugate cracks in the rock mass under complex ground stress conditions can be studied.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: on the one hand, the embodiment of the present application provides a method for simulating the crack development and fragmentation process of a fractured rock mass, comprising: S1: Prepare cement mortar with appropriate strength and place the cement mortar into a cubic mold; S2: After the cement mortar is initially set, a crack combination is set on the compression surface of the cement mortar block to form a specimen. A vertical first reference axis and a second reference axis are set on the surface of the cement mortar block. The crack combination includes a first crack group and a second crack group. The two cracks of the first crack group are set on both sides of the first reference axis, and the angles with the first reference axis are respectively and The second crack groups are respectively arranged on both sides of the second reference axis, and the angles between them and the second reference axis are and , the middles of all cracks intersect at the midpoint of the surface; S3: Cyclic stress loading on the compression surface; S4: Adjust the loading stress and then cyclically load the stress until the sample breaks.

[0006] In some embodiments, the size of the sample is 30*30*30 cm, and the length of the crack is 26 cm.

[0007] In some embodiments, the sample is a cube, the length of the sample is L, the depth of the crack is H, and 0.45≤H / L≤0.55 is satisfied.

[0008] In some embodiments, the number of pressure-bearing surfaces is three, and the three pressure-bearing surfaces are adjacent to each other.

[0009] In some embodiments, the cyclic loading stress comprises: S31: Initial state, the three compression surfaces are subjected to the same stress; S32: setting a stress variable Δσ, selecting any two of the three pressure surfaces, and adjusting the stress states of the two surfaces. Adjusting the stress state means that the stress of one of the pressure surfaces is increased by Δσ, and the stress of the other pressure surface is reduced by Δσ; S33: subjecting the three pressure surfaces to the same stress and restoring them to their initial state; S34: Change the two selected pressure surfaces and adjust the stress states of the two surfaces until the cycle of all pressure surfaces is completed.

[0010] In some embodiments, adjusting the magnitude of the loaded stress means adjusting the stress variable Δσ to 2Δσ after each stress loading cycle is completed.

[0011] On the other hand, an embodiment of the present application further provides a simulation device, which is applied to the method in the above embodiment, including a reaction angle and three pushing components. The reaction angle includes three abutting walls, and the normals of the three abutting walls extend along the first direction, the second direction and the third direction respectively, and the first direction, the second direction and the third direction are perpendicular to each other. Three pushing components are arranged at the reaction angle for applying pressure to the sample, and the pushing component includes a moving end, and among the three pushing components, the moving end of one of them moves along the first direction, the moving end of another one moves along the second direction, and the moving end of the third one moves along the third direction.

[0012] In some embodiments, the pushing component includes a first cavity and a first piston portion. The first cavity is arranged at the reaction angle. The first piston portion is movably accommodated in the first cavity along the axial direction of the first cavity, the first piston portion divides the interior of the first cavity into two parts, and the movable end is connected to the first piston portion.

[0013] In some embodiments, a control component is also included, the control component includes the control component, the control component includes a second cavity and a second piston part, the second cavity is arranged at the reaction angle, the axial direction of the second cavity extends along the axial direction of the drive shaft, the second piston part is movably accommodated in the second cavity along the axial direction of the second cavity, the second piston part divides the interior of the second cavity into two parts, and the two parts of the second chamber are connected to the two parts of the first chamber in a one-to-one correspondence.

[0014] In some embodiments, the control assembly further includes a drive shaft, a drive sleeve and a transmission component. The drive shaft is rotatably connected to the reaction angle, the drive sleeve is sleeved outside the peripheral wall of the drive shaft, the drive sleeve is provided with a spiral groove, and the axial direction of the spiral groove extends along the axial direction of the drive shaft. The transmission component is used to adjust the transmission state of the drive shaft and the drive sleeve, the connecting portion is connected to the second piston portion, and the connecting portion is inserted into the spiral groove.

[0015] The present invention has the following beneficial effects: This method can simulate the crack development and fragmentation process of fractured rock mass under complex geostress conditions. It can also be used to analyze rock stability and predict rock deformation, and provide reliable parameter recommendations for structural design and optimization in geotechnical engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 A schematic diagram of the crack setting of the sample of the present invention; Figure 3 It is a structural schematic diagram of the simulation device of the present invention; Figure 4 It is a structural schematic diagram of the control component of the present invention; Figure 5 It is a schematic diagram of the cooperation of the drive shaft, the drive sleeve and the connecting cable (the drive shaft and the drive sleeve move in opposite directions) of the present invention; Figure 6 It is a schematic diagram of the cooperation of the drive shaft, the drive sleeve and the connecting cable (the drive shaft and the drive sleeve move in the same direction) of the present invention; Figure 7 It is a structural schematic diagram of the driving sleeve of the present invention; Figure 8 It is a structural schematic diagram of the transmission component of the present invention; Fig. 9 It is a schematic diagram of the cooperation between the limiting tooth and the limiting part (the limiting tooth is between the two limiting parts) of the present invention; Fig.10It is a schematic diagram of the cooperation between the limiting teeth and the limiting part (the limiting teeth are arranged between the elastic arms) of the present invention.

[0017] Figure numbers: 1-reaction angle, 2-against the wall, 3-pushing component, 4-sample, 5-first cavity, 6-first piston part, 7-moving end, 8-driving sleeve, 9-adjusting column, 10-driving shaft, 11-second piston part, 12-second cavity, 13-connecting part, 14-spiral groove, 15-limiting tooth, 16-transmission ring, 17-connecting rope, 18-push ring, 19-limiting part, 20-elastic arm. DETAILED DESCRIPTION

[0018] 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 only part of the embodiments of the present invention, not all of the embodiments. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0019] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0020] On the one hand, an embodiment of the present application provides a method for simulating the crack development and fragmentation process of a fractured rock mass, comprising: S1: Prepare cement mortar with appropriate strength and place the cement mortar into a cubic mold. In the cubic mold, the cement mortar can form a cubic specimen 4 structure; S2: After the cement mortar is initially set, a crack combination is set on the pressure surface of the cement mortar block to form a sample 4. A vertical first reference axis and a second reference axis are set on the surface of the cement mortar block. The crack combination includes a first crack group and a second crack group. The two cracks of the first crack group are set on both sides of the first reference axis, and the angles with the first reference axis are respectively and The second crack groups are respectively arranged on both sides of the second reference axis, and the angles between them and the second reference axis are and , the middles of all cracks intersect at the midpoint of the surface; The crack combination can be set on multiple surfaces of the cement mortar. For example, the sample 4 may include three pressure-bearing surfaces, and the crack combinations can be respectively set on the three pressure-bearing surfaces; In rock mechanics, cracks are often formed along the direction of maximum shear stress. For rocks subjected to bidirectional compressive stress or shear stress, the direction of maximum shear stress is usually at an angle of 45° to the direction of principal stress. However, due to the heterogeneity of rocks and the complexity of stress state, the actual crack direction may deviate from the direction of the principal stress. Therefore, by introducing By adjusting the angle of the , it is possible to simulate small changes in the crack direction under different stress conditions. It can be the internal friction angle of sample 4. Further, the angles of the two cracks are set to and The symmetry of the crack system is also maintained; The middle of all cracks intersect at the midpoint of the surface. On the one hand, the stress is highly concentrated at the intersection, and placing the intersection at the midpoint increases the uniformity of stress distribution. On the other hand, it is convenient to simulate the extension process of cracks under different stress environments; The midpoint is located at the intersection of the first reference axis and the second reference axis; S3: Cyclic stress loading on the compression surface; By cyclically loading stress, on the one hand, the complex stress environment of sample 4 can be simulated, which increases the degree of simulation. On the other hand, stress difference can be generated in sample 4, thereby allowing cracks to develop; S4: adjusting the applied stress and then cyclically applying the stress until the sample 4 breaks; This method can simulate the crack development and fragmentation process of fractured rock mass under complex geostress conditions. It can also be used to analyze rock stability and predict rock deformation, and provide reliable parameter recommendations for structural design and optimization in geotechnical engineering.

[0021] In some embodiments, the size of the sample 4 is 30*30*30 cm, and the length of the crack is 26 cm.

[0022] Longer cracks make the expansion, intersection and conjugation of the cracks more obvious, making it easier for experimenters to observe and record, thereby improving the accuracy and reliability of experimental data.

[0023] In some embodiments, the sample 4 is a cube, the length of the sample 4 is L, the depth of the crack is H, and 0.45≤H / L≤0.55 is satisfied.

[0024] For example, when the size of sample 4 is 30*30*30 cm, the crack depth can be set to 13.5 cm, 15 cm or 16.5 cm. The advantage of this setting is that the crack will not be too shallow to observe its expansion process, nor will it be too deep to control its impact range.

[0025] In some embodiments, the number of pressure-bearing surfaces is three, and the three pressure-bearing surfaces are adjacent to each other.

[0026] The three pressure surfaces are adjacent to each other, that is, the three pressure surfaces intersect at a vertex of the sample 4.

[0027] By setting three compression surfaces and applying pressure to the compression surfaces, the multi-directional stresses on the specimen 4 in three-dimensional space can be simulated, making the stress state of the specimen 4 closer to the actual stress condition and increasing the simulation degree of the development of the conjugate joints.

[0028] In some embodiments, the cyclic loading stress comprises: S31: Initial state, the three compression surfaces are subjected to the same stress; S32: setting a stress variable Δσ, selecting any two of the three pressure surfaces, and adjusting the stress states of the two surfaces. Adjusting the stress state means that the stress of one of the pressure surfaces is increased by Δσ, and the stress of the other pressure surface is reduced by Δσ; S33: subjecting the three pressure surfaces to the same stress and restoring them to their initial state; S34: changing the two selected pressure surfaces and adjusting the stress states of the two surfaces until all the pressure surfaces are cycled; On the one hand, sample 4 is often subjected to complex and variable stresses in the real environment, and these stresses may come from different directions. By selecting two of the three pressure surfaces for stress adjustment, the different stress states of sample 4 in different directions can be simulated. On the other hand, the stress variable Δσ can produce a stress difference between the two surfaces of sample 4, thereby allowing cracks in sample 4 to develop. On the other hand, rock mechanics research shows that rock failure is often related to stress concentration and stress difference in a specific direction. By selecting two surfaces for pressure adjustment, the effects of such stress concentration and stress difference on rock failure can be simulated more directly.

[0029] In some embodiments, adjusting the magnitude of the loaded stress means adjusting the stress variable Δσ to 2Δσ after each stress loading cycle is completed.

[0030] By increasing the value of Δσ, on the one hand, the development process of cracks in specimen 4 under different stress levels can be simulated. On the other hand, specimen 4 can reach the limit state, and thus specimen 4 can be destroyed.

[0031] It should be noted that adjusting the stress variable Δσ to 2Δσ means adjusting the stress variable according to the Δσ of the last stress loading cycle, rather than according to the initial Δσ value. For example, the stress variable can be Δσ, 2Δσ, or 4Δσ.

[0032] On the other hand, the embodiment of the present application further provides a simulation device, which is applied to the method in the above embodiment, including a reaction angle 1 and three pushing components 3. The reaction angle 1 includes three abutting walls 2, and the normals of the three abutting walls 2 extend along the first direction, the second direction and the third direction respectively, and the first direction, the second direction and the third direction are perpendicular to each other. The three pushing components 3 are arranged at the reaction angle 1, and are used to apply pressure to the sample 4. The pushing components 3 include a moving end 7. Among the three pushing components 3, the moving end 7 of one moves along the first direction, the moving end 7 of another moves along the second direction, and the moving end 7 of the third moves along the third direction.

[0033] The reaction angle 1 can be formed using the inner corner of a box, so that the simulation process can be carried out in the box, increasing the safety of the simulation process.

[0034] The first direction may be the direction indicated by the X-axis in the figure, the second direction may be the direction indicated by the Y-axis in the figure, and the third direction may be the direction indicated by the Z-axis in the figure.

[0035] The three abutting walls 2 are respectively arranged opposite to the moving ends 7 of the three pushing components 3 in a one-to-one correspondence, so that when the moving ends 7 apply pressure to the sample 4, the three abutting walls 2 can play a supporting role.

[0036] The sample 4 is pressurized by the moving end 7 to simulate the situation where the sample 4 is subjected to complex ground stress, so that the cracks of the sample 4 can further develop.

[0037] In some embodiments, the simulation device may further include a micrometer for measuring cracks, and may further include an acoustic emission component for detecting cracks. The structure and working principle of the micrometer and the acoustic emission component are well known to those skilled in the art and will not be described in detail here.

[0038] In some embodiments, the pushing component 3 includes a first cavity 5 and a first piston portion 6. The first cavity 5 is disposed at a reaction angle 1. The first piston portion 6 is movably accommodated in the first cavity 5 along the axial direction of the first cavity 5, and the first piston portion 6 divides the interior of the first cavity 5 into two parts, and the moving end 7 is connected to the first piston portion 6; The first piston portion 6 is accommodated in the first cavity 5 so that the first piston portion 6 can move along the first cavity 5; The first piston part 6 divides the interior of the first cavity 5 into two parts, and the two parts are arranged along the axial direction of the first cavity 5. When the volume of the medium in the two parts changes, the first piston part 6 can be driven to move. For example, the two parts can be a first part and a second part. When the amount of the medium in the first part increases, the amount of the medium in the second part decreases. At this time, the first piston part 6 will move from the first part to the second part, and then the moving end 7 can move driven by the first piston part 6. The specific connection method of the moving end 7 and the first piston part 6 can be selected from the existing structure, which will not be repeated here.

[0039] In some embodiments, a control assembly is further included, the control assembly includes a control component, the control component includes a second cavity 12 and a second piston portion 11, the second cavity 12 is arranged at the reaction angle 1, the axial direction of the second cavity 12 extends along the axial direction of the drive shaft 10, the second piston portion 11 is movably accommodated in the second cavity 12 along the axial direction of the second cavity 12, the second piston portion 11 divides the interior of the second cavity 12 into two parts, and the two parts of the second cavity are connected to the two parts of the first cavity one by one; The second piston part 11 divides the interior of the second cavity 12 into two parts, and the two parts are arranged along the axial direction of the second cavity 12. When the volume of the medium in the two parts changes, the second piston part 11 can be driven to move. For example, the two parts can be the third part and the fourth part. When the amount of the medium in the third part increases, the amount of the medium in the fourth part decreases. At this time, the second piston part 11 will move from the third part to the fourth part; In an embodiment in which the first cavity 5 includes a first part and a second part, the third part can be connected to the first part, and the fourth part can be connected to the third part, so that when the volume of the medium in the third part and the fourth part changes, the volume of the medium in the first part and the second part can also change, that is, the movement of the first piston part 6 can be controlled by the second piston part 11, and the movement of the movable end 7 can be controlled.

[0040] In some embodiments, the control assembly further includes a drive shaft 10, a drive sleeve 8 and a transmission component. The drive shaft 10 is rotatably connected to the reaction angle 1, the drive sleeve 8 is sleeved outside the peripheral wall of the drive shaft 10, and the drive sleeve 8 is provided with a spiral groove 14, and the axial direction of the spiral groove 14 extends along the axial direction of the drive shaft 10. The transmission component is used to adjust the transmission state of the drive shaft 10 and the drive sleeve 8, the connecting portion 13 is connected to the second piston portion 11, and the connecting portion 13 is inserted into the spiral groove 14; The driving sleeve 8 can be rotatably connected to the reaction angle 1, and the driving shaft 10 is used to drive the driving sleeve 8 to rotate; The number of the driving sleeves 8 may be consistent with the number of the pushing components 3, and a plurality of driving sleeves 8 may be arranged at intervals on the driving shaft 10; The connecting portion 13 is connected to the second piston portion 11, so that the connecting portion 13 can drive the second piston portion 11 to move. It should be noted that in the embodiment of the present application, the second piston portion 11 can only move relative to the second cavity 12, but cannot rotate relative to the second piston portion 11; Since the connecting portion 13 is inserted into the spiral groove 14 of the driving sleeve 8, the connecting portion 13 can move axially relative to the driving sleeve 8 during the rotation of the driving sleeve 8, and then the second piston portion 11 moves relative to the second cavity 12, and the first piston portion 6 also moves relative to the first cavity 5. Finally, the movable end 7 applies pressure to the sample 4 driven by the first piston portion 6.

[0041] In conventional technology, the three pushing components 3 are independent components, so the three pushing components 3 need to be controlled separately, which makes the circuit complicated on the one hand, and reduces the synchronization rate of the three pushing components 3 on the other hand. In the embodiment of the present application, the driving shaft 10 rotates to drive the driving sleeve 8 to rotate, thereby enabling the three pushing components 3 to work. On the one hand, the structure is simple and reliable, and on the other hand, the three pushing components 3 can move synchronously and apply pressure to the sample 4 synchronously.

[0042] In the embodiment of the present application, the medium in the first chamber and the second chamber may be gas, which has a certain compressibility, so that even if the three pushing components 3 are all driven by one driving shaft 10, the three pushing components 3 can still apply pressure to the sample 4 respectively.

[0043] Of course, in other embodiments, the connecting part 13 may not be driven by the driving sleeve 8, but the flow of the medium between the first chamber and the second chamber may be directly controlled by a hydraulic device to move the first piston part 6. The hydraulic device can be selected from existing devices and will not be described in detail here.

[0044] In some embodiments, the transmission component includes a transmission ring 16, a connecting cable 17 and a limiting portion 19. The transmission ring 16 is sleeved on the drive shaft 10, and a limiting tooth 15 is provided on the inner circumferential wall of the transmission ring 16 around the circumference of the transmission ring 16. The connecting cable 17 is connected to the transmission ring 16 and the drive sleeve 8, and the limiting portion 19 is rotatably connected to the drive shaft 10, and the rotation axis of the limiting portion 19 is perpendicular to the axial direction of the drive shaft 10. The limiting portion 19 cooperates with the limiting tooth 15 to make the transmission ring 16 and the drive shaft 10 rotate synchronously; Under the action of the transmission component, the drive shaft 10 can be connected or disconnected with the drive sleeve 8; The transmission ring 16 can be rotatably connected to the reaction angle 1; The transmission ring 16 is sleeved on the drive shaft 10 so that the transmission ring 16 can rotate relative to the drive shaft 10; The transmission ring 16 is connected to the drive sleeve 8 via a connecting cable 17, so that when the transmission ring 16 rotates, the drive sleeve 8 can be driven to rotate together; The limiting portion 19 is rotatably connected to the drive shaft 10, so that the limiting portion 19 can have two states, one is that the limiting portion 19 contacts the limiting teeth 15, at this time, when the drive shaft 10 rotates, the transmission ring 16 rotates together with the drive shaft 10, thereby enabling the drive sleeve 8 to rotate, and the other is that the limiting portion 19 does not contact the limiting teeth 15, at this time, when the drive shaft 10 rotates, it will not drive the transmission ring 16 to rotate together; The advantage of connecting the transmission ring 16 and the drive sleeve 8 through the connecting cable 17 is that, on the one hand, the transmission structure is simpler and more reliable. On the other hand, the control method for the three pushing components 3 is increased. For example, by adjusting the position of the transmission ring 16 relative to the drive shaft 10 in the initial state, the time when the pushing component 3 starts working and the parameters of the pressure applied by the pushing component 3 to the sample 4 when the drive shaft 10 rotates can be adjusted. On the other hand, the connecting cable 17 is set to a bent state, and when the drive shaft 10 rotates, the drive sleeve 8 can rotate in the opposite direction relative to the drive shaft 10. When the connecting cable 17 is straightened, when the drive shaft 10 rotates, the drive sleeve 8 rotates in the same direction as the drive shaft 10. That is, under the premise that one drive shaft 10 is used as the power source, the rotation directions of the various drive sleeves 8 can be different. On the other hand, the drive sleeve 8 and the drive shaft 10 can be set at intervals so that no wear occurs between the two.

[0045] In other embodiments, the transmission ring 16 and the connecting rope 17 can be eliminated as needed, and the limiting teeth 15 can be set on the inner wall of the driving sleeve 8. When the limiting portion 19 contacts the limiting teeth 15 on the inner wall of the driving sleeve 8, the driving sleeve 8 and the driving shaft 10 are connected in transmission.

[0046] In some embodiments, the transmission component also includes a push ring 18, and an elastic member is arranged between the limiting portion 19 and the driving shaft 10, and the elastic member is used to provide an elastic force to rotate the limiting portion 19 in a direction close to the driving shaft 10. The push ring 18 is movably mounted on the driving shaft 10 along the axial direction of the driving shaft 10, and the limiting portion 19 abuts against the outer peripheral wall of the push ring 18.

[0047] The elastic member can be a spring or a torsion spring.

[0048] Under the action of the elastic member, the limiting portion 19 has a tendency to move away from the transmission ring 16 .

[0049] The push ring 18 can move along the axial direction of the drive shaft 10 , so that the push ring 18 can push the limiting portion 19 to rotate, and then the limiting portion 19 can contact the transmission ring 16 or move away from the transmission ring 16 .

[0050] In other embodiments, two push rings 18 may be provided at intervals along the axial direction of the drive shaft 10 , one for pushing the limiting portion 19 toward the limiting tooth 15 , and the other for pushing the limiting portion 19 from the limiting tooth 15 toward the drive shaft 10 .

[0051] In the embodiment of the present application, the power source of the drive shaft 10 can be selected from the existing structure, which will not be described in detail here. At the same time, the reaction angle 1 can be provided with a driving component, which is used to drive the transmission ring 16 to rotate relative to the drive shaft 10 when the transmission ring 16 and the limiter 19 are disconnected, so as to adjust the position of the transmission ring 16. The drive shaft 10 can also be provided with a driving component, which is used to drive the push ring 18 to move relative to the drive shaft 10. The driving component can be selected from the existing structure, which will not be described in detail here.

[0052] In some embodiments, the limiting portion 19 includes a first end close to the transmission ring 16, the first end includes two elastic arms 20, and the first end includes a first state and a second state. In the first state, the two elastic arms 20 are inserted between two adjacent limiting teeth 15, and in the second state, a limiting tooth 15 is arranged between the two elastic arms 20.

[0053] The limiting portion 19 may be made of a material capable of elastic deformation, so that the two elastic arms 20 can be elastically deformed.

[0054] If the limiting portion 19 is an integral structure, when the limiting portion 19 contacts the limiting teeth 15, there may be two situations. One is that the limiting portion 19 is just stuck between the two limiting teeth 15, and the other is that the limiting portion 19 is against the top of the limiting teeth 15. At this time, the transmission ring 16 needs to rotate a certain angle before the limiting portion 19 can be stuck between the two limiting teeth 15, which may also cause errors in the displacement of the moving end 7 of the pushing component 3.

[0055] In the embodiment of the present application, in the first state, the limiting portion 19 can be just inserted between the two limiting teeth 15. If the limiting portion 19 is against the top of the limiting tooth 15, when the limiting portion 19 switches to the second state, that is, the two elastic arms 20 are separated, each elastic arm 20 is inserted between the two limiting teeth 15. At the same time, a limiting tooth 15 is arranged between the two elastic arms 20, so that the limiting portion 19 can play a limiting role without the need for the transmission portion to rotate.

[0056] In some embodiments, an adjustment column 9 is further included, and the adjustment column 9 is disposed between the transmission ring 16 and the driving sleeve 8; The position of the adjustment column 9 relative to the reaction angle 1 can be adjusted, so that the position of the adjustment column 9 between the transmission ring 16 and the drive sleeve 8 can also be adjusted; On the one hand, the adjusting column 9 can play a limiting role, that is, if the connecting cable 17 is in a straight state, when the connecting cable 17 contacts the adjusting column 9, the transmission ring 16 can no longer drive the driving sleeve 8 to move further, thereby limiting the travel of the driving sleeve 8. On the other hand, the adjusting column 9 can also enable the driving sleeve 8 to move in the reverse direction, that is, by adjusting the position of the transmission ring 16 relative to the adjusting column 9, the connecting cable 17 can be initially in a bent state, and the adjusting column 9 is at the inner bend of the connecting cable 17. At this time, when the driving shaft 10 rotates, the driving sleeve 8 can be driven to rotate in the reverse direction.

[0057] The above embodiments are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations, modifications, and substitutions made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for simulating the crack development and fragmentation process of a fractured rock mass, characterized in that: include: Prepare cement mortar with appropriate strength and place the cement mortar into a cubic mold; After the cement mortar is initially set, a crack combination is arranged on the pressure surface of the cement mortar block to form a test specimen (4), wherein a vertical first reference axis and a second reference axis are arranged on the surface of the cement mortar block, and the crack combination includes a first crack group and a second crack group, wherein the two cracks of the first crack group are arranged on both sides of the first reference axis, and the angles between the first crack group and the first reference axis are respectively and The second crack groups are respectively arranged on both sides of the second reference axis, and the angles between them and the second reference axis are and , the middles of all cracks intersect at the midpoint of the surface; Cyclic stress loading is applied to the compression surface; The magnitude of the applied stress is adjusted and then the stress is applied cyclically until the sample (4) breaks.

2. The method for simulating the crack development and fragmentation process of a fractured rock mass according to claim 1, characterized in that: The size of the sample (4) is 30*30*30 cm, and the length of the crack is 26 cm.

3. The method for simulating the crack development and fragmentation process of a fractured rock mass according to claim 1, characterized in that: The sample (4) is a cube, the length of the sample (4) is L, the depth of the crack is H, and 0.45≤H / L≤0.55 is satisfied.

4. The method for simulating the crack development and fragmentation process of a fractured rock mass according to claim 1, characterized in that: The three pressure-bearing surfaces are arranged adjacent to each other.

5. The method for simulating the crack development and fragmentation process of a fractured rock mass according to claim 1, characterized in that: The cyclic loading stress includes: In the initial state, the three compression surfaces are subjected to the same stress; Set the stress variable Δσ, select any two of the three pressure surfaces, and adjust the stress state of the two. Adjusting the stress state means that the stress of one pressure surface increases by Δσ, and the stress of the other pressure surface decreases by Δσ; The three compression surfaces are subjected to the same stress and restored to their initial state; Change the two selected pressure surfaces and adjust their stress states until the cycle is completed for all pressure surfaces.

6. The method for simulating the crack development and fragmentation process of a fractured rock mass according to claim 5, characterized in that: The adjustment of the magnitude of the loaded stress means that after each cyclic stress loading is completed, the stress variable Δσ is adjusted to 2Δσ.

7. A simulation device, applied to the method according to any one of claims 1 to 6, characterized in that: include: A reaction angle (1), the reaction angle (1) comprising three abutting walls (2), the normals of the three abutting walls (2) extending along a first direction, a second direction and a third direction respectively, the first direction, the second direction and the third direction being perpendicular to each other; Three pushing components (3) are arranged at the reaction angle (1) and are used to apply pressure to the sample (4). The pushing components (3) include a moving end (7). Among the three pushing components (3), the moving end (7) of one moves along the first direction, the moving end (7) of another moves along the second direction, and the moving end (7) of the third moves along the third direction.

8. The simulation device according to claim 7, characterized in that: The pushing component (3) comprises: A first cavity (5) is arranged at the reaction angle (1); The first piston part (6) is movably accommodated in the first cavity (5) along the axial direction of the first cavity (5); the first piston part (6) divides the interior of the first cavity (5) into two parts; and the movable end (7) is connected to the first piston part (6).

9. The simulation device according to claim 8, characterized in that The invention also comprises a control assembly, wherein the control assembly comprises the control component, and the control component comprises a second cavity (12) and a second piston portion (11), wherein the second cavity (12) is arranged at the reaction angle (1), and the axial direction of the second cavity (12) extends along the axial direction of the drive shaft (10), and the second piston portion (11) is movably accommodated in the second cavity (12) along the axial direction of the second cavity (12), and the second piston portion (11) divides the interior of the second cavity (12) into two parts, and the two parts of the second cavity are connected to the two parts of the first cavity in a one-to-one correspondence.

10. The simulation device according to claim 9, characterized in that The control component also includes: A drive shaft (10) rotatably connected to the reaction angle (1); A drive sleeve (8) is sleeved outside the peripheral wall of the drive shaft (10), the drive sleeve (8) being provided with a spiral groove (14), the axial direction of the spiral groove (14) extending along the axial direction of the drive shaft (10); A transmission component, used for adjusting the transmission state of the drive shaft (10) and the drive sleeve (8); The connecting portion (13) is connected to the second piston portion (11), and the connecting portion (13) is inserted into the spiral groove (14).

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