An experimental method for prefabricating three-dimensional cracks in rock mass using similar materials

Abstract

The present invention provides an experimental method for prefabricating three-dimensional cracks in a rock mass with similar materials. The method is carried out using a matching experimental device, which includes a template installation mechanism, a prefabricated rock mass container, a base, and a template installation mechanism fixing seat. The template of the template installation mechanism uses a flexible template and has an adjustment mechanism for accurately adjusting the extension angle of the flexible template. At the same time, a size adjustment mechanism is also provided for the prefabricated rock mass container. When prefabricating a rock mass with cracks, the experimental device is used for prefabrication according to the experimental method, and a prefabricated rock mass test block with a rock mass crack direction and a rock mass test piece size that are accurately adjustable can be obtained.

Description

Technical Field

[0001] The invention relates to the technical field of processing simulated rock samples for rock mechanics experiments, in particular to an experimental method for prefabricating three-dimensional cracks in rock masses using similar materials. Background Art

[0002] There are a large number of primary cracks in the engineering rock mass. These cracks will cause stress redistribution inside the rock during the process of engineering excavation and disturbance, which will affect the mechanical characteristics of the rock such as strength and deformation, and ultimately affect the stability of the rock mass engineering. Therefore, it is particularly important to study the mechanical response mechanism of the fractured rock mass. However, considering the uniformity of fracture parameters such as the number of fractures, fracture forms, fracture sizes, and fracture positions, it is quite difficult to process fractured specimens in indoor experiments. Therefore, using similar materials to prefabricate three-dimensional fractures in the rock mass has become a common option. The main preparation process is to simulate the fractures inside the rock sample by pre-embedding a sheet mold with a small bonding effect with similar materials before pouring. However, this method has the following disadvantages: 1. The fractures produced are simple and single in form, and it is difficult to process three-dimensional fractures with various forms. 2. The production process is all controlled manually, the accuracy of the fracture position is poor, and it is difficult to achieve multiple restoration of the fractures in the specimen. 3. The bonding effect between the sheet mold and the specimen will have a certain impact on the strength of the specimen. A physical simulation system for prefabricating rock mass with fracture surfaces of different orientations is disclosed in a Chinese patent application with patent number 202011590338.9. It realizes the addition of fractures of different penetration depths and angles in rock and soil samples, and can compact the samples by transmitting force through the pressure plate, which improves efficiency when a large number of simulated rock mass samples with fracture surfaces of arbitrary orientations and different penetration degrees need to be prefabricated. However, the control of the fracture angle by this technical solution is rough and discontinuous, and the angle of the fracture in the sample cannot be accurately controlled. In addition, the size of the sample produced by this technical solution is fixed, and it is impossible to use the same device to produce samples of different sizes. Summary of the invention

[0003] In view of this, the main purpose of the present invention is to provide a method for prefabricating three-dimensional rock fractures using similar materials that can solve the problems of existing rock fracture prefabricated part processing devices, such as the control of fracture angles is too rough and discontinuous, and the angle of the fractures in the sample cannot be accurately controlled, and the size of the manufactured specimens is fixed, making it impossible to use the same device to manufacture specimens of different sizes.

[0004] The technical solution adopted by the present invention is: prefabricating a three-dimensional rock mass fracture test block comprises the following steps:

[0005] Step 1: Prepare the experimental equipment required for the experiment and place it on a flat ground;

[0006] Step 2: Determine the size of the prefabricated rock mass specimen according to the experimental requirements, and adjust the container adjustment structure so that the height and bottom side length of the prefabricated rock mass container are adapted to the size of the prefabricated rock mass specimen;

[0007] Step 3: The position of the template installation mechanism fixing seat on the base is precisely controlled according to the displacement size scale on the base, so that the positions of the template extension slits of the template installation mechanisms arranged opposite to each other on the left and right are relatively staggered, thereby controlling the angle of the flexible template extending from the crack relative to the front and rear surfaces;

[0008] Step 4: First turn the coarse adjustment handle to get the approximate relative angle between the flexible template and the bottom surface, and then turn the fine adjustment handle according to the scale to accurately get the relative angle between the flexible template and the bottom surface;

[0009] Step 5: Pull out the flexible template into the rock prefabricated container. After the configuration is completed, pour cement mortar into the prefabricated rock container. After the cement mortar solidifies, remove the rock prefabricated container, pull out the flexible template, seal the left and right end faces of the rock prefabricated part with two plates, and inject cement mortar into the pulled out flexible gap. After it solidifies, a weak surface is formed here, which is the prefabricated crack required by the experiment.

[0010] The experimental setup includes:

[0011] The template installation mechanism has two template installation mechanisms, which are arranged opposite to each other on the left and right. The template installation mechanism consists of a template angle adjustment part and a template fixing part; the template angle adjustment part includes a fine adjustment handle, a coarse adjustment handle, an angle adjustment indicator disk, and an angle adjustment disk; the angle adjustment indicator disk is in the shape of a disk, an outer end of which is provided with an angle scale, and an inner end is fitted with an angle adjustment disk. The connecting end of the angle adjustment disk and the angle adjustment indicator disk is an internal gear structure, and the other end is an installation cavity of the template fixing part. A pair of coarse adjustment gears and a pair of fine adjustment gears are symmetrically arranged on both sides of the axis of the angle adjustment disk, and the coarse adjustment gear and the fine adjustment gear are respectively meshed with the inner gear of the angle adjustment disk. One end of the coarse adjustment handle is an adjustment end The angle adjustment indicator plate is exposed outside the angle adjustment indicator plate, and the other end passes through the angle adjustment indicator plate and extends into the angle adjustment plate, on which a gear is mounted to mesh with the coarse adjustment gear; one end of the fine adjustment handle is an adjustment end exposed outside the angle adjustment indicator plate, and the other end passes through the coarse adjustment handle and extends into the angle adjustment plate, on which a gear is mounted to mesh with the fine adjustment gear; an inwardly concave slide groove is arranged in the cavity on the angle adjustment plate, the cavity is closed by an end plate, a template extension slot is opened on the end plate, a slider is arranged in the slide groove, a template mounting rod is fixed on the slider, a flexible template is wound around the template mounting rod, and the flexible template extends through the template extension slot to form a template fixing portion;

[0012] A prefabricated rock container, the prefabricated rock container is surrounded by a bottom plate, a front side plate and a rear side plate perpendicular to the bottom plate, and end plates of the angle adjustment plate respectively located on the left and right sides of the prefabricated rock container, the upper end of the prefabricated rock container is open; a container adjustment structure is provided on the bottom plate, and a screw sleeve extending vertically downward is provided on the bottom surface of the bottom plate;

[0013] A base, on which a screw rod extending vertically upward is provided, and the prefabricated rock mass container is mounted on the screw rod through the screw rod sleeve and can move up and down along the screw rod;

[0014] A template installation mechanism fixing seat, wherein the template installation mechanism is fixed to the upper portion of the template installation mechanism fixing seat, and the lower portion of the template installation mechanism fixing seat is connected to the base.

[0015] As a preferred solution, the container adjustment structure is that four corners of the top of the prefabricated rock container are respectively provided with screw mounting long holes that penetrate the front side plate and the rear side plate up and down, and four corners of the side of the prefabricated rock container are respectively provided with telescopic rod mounting long holes that penetrate the front side plate and the rear side plate left and right, the screw mounting long holes intersect with the telescopic rod mounting long holes, a telescopic rod is inserted in each of the telescopic rod mounting long holes, a screw is inserted in each of the screw mounting long holes, the telescopic rod and the screw are connected at the intersection of the screw mounting long holes and the telescopic rod mounting long holes, four adjusting rods facing the screw are inserted at the upper end of the screw sleeve, the end of each adjusting rod is a screw structure, which is respectively inserted into the adjusting hole of the adjusting positioning block and cooperates with the adjusting gear, and the adjusting gear controls the depth of the adjusting rod extending into the adjusting hole, a screw hole is provided on the adjusting positioning block along its vertical direction, the screw is inserted in the screw hole, and its lower end is an adjusting handle.

[0016] As a preferred embodiment, the base is composed of a bottom plate, a front end plate and a rear end plate installed on the bottom plate, and slide grooves are respectively provided on the inner sides of the front end plate and the rear end plate, and two pairs of sliders are respectively installed in the slide grooves, and each pair of the sliders are connected by a connecting rod, and a positioning hole is provided on the connecting rod, and a positioning bolt is installed in the positioning hole and passes through the positioning hole to be connected to the bottom plate, and the template mounting mechanism fixing seat is installed on the connecting rod.

[0017] As a preferred solution, the middle parts of the upper ends of the front end plate and the rear end plate are connected by a connecting beam, the screw is fixed to the middle part of the connecting beam, and the screw sleeve of the prefabricated rock container is fixed to the screw by an adjusting wheel, and the screw sleeve is controlled to move up and down by the adjusting wheel.

[0018] As a preferred solution, a template base positioning screw is arranged parallel to one side of the connecting rod, both ends of the template base positioning screw are fixed on the sliding block, and the template mounting mechanism fixing seat is installed on the positioning screw and the connecting rod through the mounting holes opened thereon.

[0019] As a preferred solution, a gear that cooperates with the positioning screw is provided in the template installation mechanism fixing seat, and the gear is meshed with an adjusting gear arranged in parallel. The axle of the adjusting gear extends out of the template installation mechanism fixing seat and is connected to an adjusting handle. The template installation mechanism fixing seat is controlled to move on the positioning screw by rotating the adjusting handle.

[0020] As a preferred solution, a template installation mechanism fixed seat displacement adjustment scale is provided on one side of the positioning screw on the base; and a slider displacement scale is provided on the front end plate of the base.

[0021] As a preferred solution, a spiral spring is installed on the template installation rod, and the end of the flexible template is connected to the outer end of the spiral spring.

[0022] As a preferred solution, a raised gear shaft is provided on the angle adjustment disk at its axial position, the gear of the fine adjustment handle is installed on the gear shaft, and a pair of raised secondary steps are symmetrically provided on both sides of the gear shaft as the gear shaft, wherein the large step is the gear shaft of the fine adjustment gear, and the small step is the gear shaft of the coarse adjustment gear.

[0023] The present invention has the following advantages:

[0024] 1. The present invention adopts a template installation mechanism that can combine coarse adjustment and fine adjustment of the relative angle between the template and the bottom surface to obtain a precise relative angle between the template and the bottom surface. At the same time, the slider adjustment structure of the device base and the screw positioning adjustment mechanism of the template installation mechanism base are used to accurately control the angle of the template relative to the front and rear surfaces, thereby realizing precise control of the position of the through cracks inside the prefabricated rock mass test block.

[0025] 2. The present invention realizes precise control of the size of the prefabricated rock container by setting up a prefabricated rock container adjustment structure, effectively solving the problem in the background technology that samples of various sizes cannot be produced using the same device.

[0026] 3. The crack template of the present invention adopts a flexible template with superior deformation ability and is installed through a scroll spring. The template can be retracted and released more conveniently, and the production efficiency is higher. At the same time, it can also reduce the strength problem caused by the bonding between the sheet mold and the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention.

[0028] Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention.

[0029] Figure 3 It is a structural schematic diagram of the template installation mechanism of the present invention.

[0030] Figure 4 It is a schematic diagram of the exploded structure of the template installation mechanism of the present invention.

[0031] Figure 5 It is a structural schematic diagram of the prefabricated rock mass container of the present invention.

[0032] Figure 6 yes Figure 5 Bottom view of .

[0033] Figure 7 It is a three-dimensional structural schematic diagram of the prefabricated rock container of the present invention

[0034] Figure 8 It is a cross-sectional view of the adjustment positioning block 2-4.

[0035] Fig. 9 It is a schematic diagram of the explosion structure of the prefabricated rock container of the present invention.

[0036] Fig.10 It is a structural schematic diagram of a base of the present invention.

[0037] Fig.11 It is a structural schematic diagram of a template installation mechanism fixing seat of the present invention.

[0038] Fig.12 It is a three-dimensional structural schematic diagram of the template installation mechanism fixing seat of the present invention.

[0039] Detailed description of the attached drawings: template installation mechanism 1, prefabricated rock container 2, base 3, template installation mechanism fixing seat 4, fine adjustment handle 1-1, coarse adjustment handle 1-2, angle adjustment indicator plate 1-3, angle adjustment plate 1-4, coarse adjustment gear 1-5, fine adjustment gear 1-6, coarse adjustment gear shaft 1-7, fine adjustment gear shaft 1-8, gear 1-9, flexible template 1-10, template installation rod 1-11, slider 1-12, slide 1-13, end plate 1-14, gear shaft 1-15, gear 1-16, template extension gap 1-17, internal gear 1-18, volute spring 1-19, telescopic rod 2-1, screw 2-2, screw Rod sleeve 2-3, adjusting wheel 2-4, adjusting rod 2-5, adjusting positioning block 2-6, screw mounting long hole 2-7, telescopic rod mounting long hole 2-8, screw hole 2-6-1, adjusting hole 2-6-2, slider 3-1, connecting beam 3-2, rear end plate 3-3, front end plate 3-4, positioning bolt 3-5, connecting rod 3-6, positioning screw 3-7, template installation mechanism fixed seat displacement adjustment scale 3-8, slider displacement scale 3-9, screw 3-10, bottom plate 3-11, slide groove 3-12, adjusting handle 4-1, adjusting gear 4-2, gear 4-3, screw mounting hole 4-4, connecting rod mounting hole 4-5. DETAILED DESCRIPTION

[0040] The present invention will be further described and illustrated below in conjunction with specific embodiments and accompanying drawings:

[0041] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] An experimental method for prefabricating three-dimensional cracks in rock mass using similar materials:

[0044] Step 1: Prepare the experimental equipment required for the experiment and place it on a flat ground;

[0045] Step 2: Determine the size of the prefabricated rock mass specimen according to the experimental requirements, and adjust the container adjustment structure so that the height and bottom side length of the prefabricated rock mass container are adapted to the size of the prefabricated rock mass specimen;

[0046] Step 3: The position of the template installation mechanism fixing seat on the base is precisely controlled according to the displacement size scale on the base, so that the positions of the template extension slits of the template installation mechanisms arranged opposite to each other on the left and right are relatively staggered, thereby controlling the angle of the flexible template extending from the crack relative to the front and rear surfaces;

[0047] Step 4: First turn the coarse adjustment handle to get the approximate relative angle between the flexible template and the bottom surface, and then turn the fine adjustment handle according to the scale to accurately get the relative angle between the flexible template and the bottom surface;

[0048] Step 5: Pull out the flexible template into the rock prefabricated container. After the configuration is completed, pour cement mortar into the prefabricated rock container. After the cement mortar solidifies, remove the rock prefabricated container, pull out the flexible template, seal the left and right end faces of the rock prefabricated part with two plates, and inject cement mortar into the pulled out flexible gap. After it solidifies, a weak surface is formed here, which is the prefabricated crack required by the experiment.

[0049] Reference Figure 1 , Figure 2 The experimental device of the present invention includes a template installation mechanism 1, a prefabricated rock container 2, a base 3, and a template installation mechanism fixing seat 4.

[0050] There are two template installation mechanisms 1, which are arranged opposite to each other on the left and right. The template installation mechanism 1 is composed of a template angle adjustment part and a template fixing part; the template angle adjustment part includes a fine adjustment handle 1-1, a coarse adjustment handle 1-2, an angle adjustment indicator disk 1-3, and an angle adjustment disk 1-4; the angle adjustment indicator disk 1-3 is in the shape of a disc, with an angle scale on its outer end, and an angle adjustment disk 1-4 mounted on its inner end. The connecting end of the angle adjustment disk 1-4 and the angle adjustment indicator disk 1-3 is an internal gear structure, and the other end is the installation cavity of the template fixing part. A raised gear shaft 1-15 is provided on the angle adjustment disk 1-4 at its axial center position, and a pair of raised secondary steps are symmetrically provided on both sides of the gear shaft 1-15 as gear shafts, wherein the large step is used as the fine adjustment gear shaft 1-8 to install the fine adjustment gear 1-6, and the small step is used as the coarse adjustment gear shaft 1-7 to install the coarse adjustment gear 1-5. The coarse adjustment gear 1-5 and the fine adjustment gear 1-6 are respectively meshed with the internal gear 1-18 of the angle adjustment disk 1-4. One end of the coarse adjustment handle 1-2 is the adjustment end exposed outside the angle adjustment indicator disk 1-3, and the other end passes through the angle adjustment indicator disk 1-3 and extends into the angle adjustment disk 1-4, on which a gear 1-16 is installed to mesh with the coarse adjustment gear 1-5; one end of the fine adjustment handle 1-1 is the adjustment end exposed outside the angle adjustment indicator disk 1-3, and the other end passes through the coarse adjustment handle 1-2 and extends into the angle adjustment disk 1-4, on which a gear 1-9 is installed to mesh with the fine adjustment gear 1-8; 1-4 is provided with a concave slide groove 1-13 in the cavity, the cavity is closed by an end plate 1-14, a template extension slot 1-17 is opened on the end plate 1-14, a slider 1-12 is provided in the slide groove 1-13, a template mounting rod 1-11 is fixed on the slider, a spiral spring 1-19 is wound around the template mounting rod 1-11, the outer end of the spiral spring 1-19 is connected to the end of the flexible template 1-10, and the flexible template 1-10 is extended through the template extension slot 1-17, as shown in FIG. Figure 3 , Figure 4 When in use, according to the crack angle requirement of the prefabricated rock mass sample and the scale indication of the angle adjustment indicator disk 1-3, the coarse adjustment handle is turned to drive the gear 1-16 to rotate, and the coarse adjustment gear 1-5 meshing therewith drives the internal gear 1-18 to rotate to realize the rotation of the angle adjustment disk 1-4, so that the flexible template 1-10 installed on the angle adjustment disk 1-4 obtains an ideal coarse adjustment angle, and then the fine adjustment handle 1-1 is turned again according to the scale indication of the angle adjustment indicator disk 1-3, so that the gear 1-9 is rotated, and the gear 1-16 meshing therewith drives the internal gear 1-18 to rotate to realize the rotation of the angle adjustment disk 1-4, so that the flexible template 1-10 installed on the angle adjustment disk 1-4 obtains an ideal fine adjustment angle.

[0051] The prefabricated rock container 2 is surrounded by a bottom plate, a front side plate and a rear side plate perpendicular to the bottom plate, and end plates 1-14 of the angle adjustment disk 1-4 respectively located on the left and right sides of the prefabricated rock container 2, and the upper end of the prefabricated rock container 2 is open; a container adjustment structure is provided on the bottom plate, and the container adjustment structure is that screw mounting long holes 2-7 that pass through the front side plate and the rear side plate up and down are respectively opened on the four corners of the top of the prefabricated rock container 2, and telescopic rod mounting long holes 2-8 that pass through the front side plate and the rear side plate left and right are respectively opened on the four corners of the side of the prefabricated rock container 2, the screw mounting long holes 2-7 are intersected with the telescopic rod mounting long holes 2-8, and a telescopic rod 2-1 is installed in each of the telescopic rod mounting long holes 2-8, and a telescopic rod 2-1 is installed in each of the screw mounting long holes 2-8. A screw rod 2-2 is inserted into the long hole 2-7, and the telescopic rod 2-2 is connected with the screw rod 2-1 at the intersection of the screw mounting long hole 2-7 and the telescopic rod mounting long hole 2-8. A screw rod sleeve 2-3 extending vertically downward is provided on the bottom surface of the bottom plate, and four adjusting rods 2-5 facing the screw rod 2-2 are inserted at the upper end of the screw sleeve 2-3. The end of each adjusting rod 2-5 is a screw structure, which extends into the adjusting hole 2-6-2 of the adjusting positioning block 2-6 and cooperates with the adjusting gear. The adjusting gear controls the depth of the adjusting rod 2-5 extending into the adjusting hole 2-6-2. A screw hole 2-6-1 is provided on the adjusting positioning block 2-6 along its vertical direction. The screw rod 2-2 is inserted into the screw hole 2-6-1, and its lower end is an adjusting handle. Figure 5 , Figure 6 , Figure 7 , Figure 8 When in use, the height of the rock mass prefabricated container 2 can be adjusted by rotating the adjustment handle at the lower end of the adjustment screw 2-2 and adjusting the positions of the four adjustment screws 2-2 in the screw holes 2-6-1 of the adjustment positioning blocks 2-6 at the same time; if the adjustment gear is rotated at the same time to control the depth of the adjustment rod 2-5 extending into the adjustment hole 2-6-2, the screw 2-2 can be driven to perform telescopic movement with the telescopic rods 2-1 connected to the screw 2-2, thereby realizing the telescopic movement of the bottom side length of the rock mass prefabricated container 2.

[0052] The base 3 is composed of a bottom plate 3-11, a front plate 3-4 and a rear plate 3-3 installed on the bottom plate 3-11, and a slide groove 3-12 is respectively provided on the inner side of the front plate 3-4 and the rear plate 3-3, and two pairs of sliders 3-1 are respectively installed in the slide groove 3-12, and each pair of the sliders 3-1 is connected by a parallel connecting rod 3-6 and a positioning screw 3-7. The middle part of the upper end of the front plate 3-4 and the rear plate 3-3 is connected by a connecting beam 3-2, and a screw 3-10 extending vertically upward is fixed in the middle part of the connecting beam 3-2. The lower end of the screw sleeve 2-3 of the prefabricated rock mass container 2 is fixed to the screw 3-10 through an adjusting wheel 2-4, and the screw sleeve 2-3 is controlled by the adjusting wheel 2-4 to move up and down along the screw 3-10. A positioning hole is provided on the connecting rod 3-6, and a positioning bolt 3-5 is installed in the positioning hole that passes through the positioning hole and is connected to the bottom plate 3-11. The template installation mechanism fixing seat 4 is installed on the connecting rod. A template installation mechanism fixing seat 4 displacement adjustment scale is provided on the base 3 at one side of the positioning screw 3-7; a slider displacement scale 3-9 is provided on the front end plate 3-4 of the base 3. Figure 8 When in use, according to the size requirements of the prefabricated rock test block, the position of the connecting rod can be fixed by rotating the positioning bolt 3-5, and the position of the slider 3-1 in the slide groove of the base can be accurately adjusted according to the slider displacement scale 3-9, so as to achieve accurate adjustment of the size of the left and right ends of the prefabricated rock test block.

[0053] The template installation mechanism 1 is fixed to the upper part of the template installation mechanism fixing seat 4 by bonding, and the lower part of the template installation mechanism fixing seat 4 is provided with a mounting hole, which is a screw mounting hole 4-4 and a connecting rod mounting hole 4-5 arranged in parallel. The template installation mechanism 1 has two groups, which are respectively passed through the screw mounting hole 4-4 and the connecting rod mounting hole 4-5 and are installed on the connecting rod 3-6 and the positioning screw 3-7 of the base 3. A gear 4-3 cooperating with the positioning screw 3-7 is provided in the template installation mechanism fixing seat 4, and the gear 4-3 is meshed with the adjustment gear 4-2 arranged in parallel. The axle of the adjustment gear 4-2 extends out of the template installation mechanism fixing seat 4 to connect the adjustment handle 4-1. By rotating the adjustment handle 4-1 and combining with the template installation mechanism fixing seat displacement adjustment scale 3-8 on the base 3, the template installation mechanism fixing seat 4 can be accurately controlled to move on the positioning screw 3-7, so that the template extension seams 1-17 of the template installation mechanisms arranged opposite to each other at the left and right ends are relatively staggered, such as Fig. 9 , Fig.10 shown.

[0054] In the embodiment of the present invention, in order to better roll up the flexible template and separate the flexible template from the rock mass test block, the flexible template can be made of fiber material or leather as needed. In order to more easily adjust the size of the prefabricated rock mass test block, the prefabricated rock mass container 2 can be made of a relatively flexible material.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. An experimental method for prefabricating three-dimensional cracks in rock mass using similar materials, characterized in that: The following steps are involved: Step 1: Prepare the experimental equipment required for the experiment and place it on a flat ground; Step 2: Determine the size of the prefabricated rock mass specimen according to the experimental requirements, and adjust the container adjustment structure so that the height and bottom side length of the prefabricated rock mass container are adapted to the size of the prefabricated rock mass specimen; Step 3: The position of the template installation mechanism fixing seat on the base is precisely controlled according to the displacement size scale on the base, so that the positions of the template extension slits of the template installation mechanisms arranged opposite to each other on the left and right are relatively staggered, thereby controlling the angle of the flexible template extending from the crack relative to the front and rear surfaces; Step 4: First turn the coarse adjustment handle to get the approximate relative angle between the flexible template and the bottom surface, and then turn the fine adjustment handle according to the scale to accurately get the relative angle between the flexible template and the bottom surface; Step 5: Pull out the flexible template to the rock mass prefabricated container. After the configuration is completed, pour cement mortar into the prefabricated rock mass container. After the cement mortar solidifies, remove the rock mass prefabricated container, pull out the flexible template, seal the left and right end faces of the rock mass prefabricated part with two plates, and inject cement mortar into the pulled out flexible gap. After it solidifies, a weak surface is formed here, that is, the prefabricated crack required by the experiment; The experimental device comprises: The template installation mechanism has two template installation mechanisms, which are arranged opposite to each other on the left and right. The template installation mechanism consists of a template angle adjustment part and a template fixing part; the template angle adjustment part includes a fine adjustment handle, a coarse adjustment handle, an angle adjustment indicator disk, and an angle adjustment disk; the angle adjustment indicator disk is in the shape of a disk, an outer end of which is provided with an angle scale, and an inner end is fitted with an angle adjustment disk. The connecting end of the angle adjustment disk and the angle adjustment indicator disk is an internal gear structure, and the other end is an installation cavity of the template fixing part. A pair of coarse adjustment gears and a pair of fine adjustment gears are symmetrically arranged on both sides of the axis of the angle adjustment disk, and the coarse adjustment gear and the fine adjustment gear are respectively meshed with the inner gear of the angle adjustment disk. One end of the coarse adjustment handle is an adjustment end The angle adjustment indicator plate is exposed outside the angle adjustment indicator plate, and the other end passes through the angle adjustment indicator plate and extends into the angle adjustment plate, on which a gear is mounted to mesh with the coarse adjustment gear; one end of the fine adjustment handle is an adjustment end exposed outside the angle adjustment indicator plate, and the other end passes through the coarse adjustment handle and extends into the angle adjustment plate, on which a gear is mounted to mesh with the fine adjustment gear; an inwardly concave slide groove is arranged in the cavity on the angle adjustment plate, the cavity is closed by an end plate, a template extension slot is opened on the end plate, a slider is arranged in the slide groove, a template mounting rod is fixed on the slider, a flexible template is wound around the template mounting rod, and the flexible template extends through the template extension slot to form a template fixing portion; A prefabricated rock container, the prefabricated rock container is surrounded by a bottom plate, a front side plate and a rear side plate perpendicular to the bottom plate, and end plates of the angle adjustment plate respectively located on the left and right sides of the prefabricated rock container, the upper end of the prefabricated rock container is open; a container adjustment structure is provided on the bottom plate, and a screw sleeve extending vertically downward is provided on the bottom surface of the bottom plate; A base, on which a screw rod extending vertically upward is provided, and the prefabricated rock mass container is mounted on the screw rod through the screw rod sleeve and can move up and down along the screw rod; A template installation mechanism fixing seat, the template installation mechanism is fixed to the upper part of the template installation mechanism fixing seat, and the lower part of the template installation mechanism fixing seat is connected to the base; The container adjustment structure is that four corners of the top of the prefabricated rock container are respectively provided with screw mounting long holes that penetrate the front side plate and the rear side plate up and down, and four corners of the side of the prefabricated rock container are respectively provided with telescopic rod mounting long holes that penetrate the front side plate and the rear side plate left and right, the screw mounting long holes intersect with the telescopic rod mounting long holes, a telescopic rod is inserted in each of the telescopic rod mounting long holes, a screw is inserted in each of the screw mounting long holes, the telescopic rod and the screw are connected at the intersection of the screw mounting long holes and the telescopic rod mounting long holes, four adjustment rods facing the screw are inserted at the upper end of the screw sleeve, the end of each adjustment rod is a screw structure, which is respectively inserted into the adjustment hole of the adjustment positioning block and cooperates with the adjustment gear, and the adjustment gear controls the depth of the adjustment rod extending into the adjustment hole, a screw hole is provided on the adjustment positioning block along its vertical direction, the screw is inserted in the screw hole, and the lower end of the screw is an adjustment handle; the prefabricated rock container is made of flexible material; The base is composed of a bottom plate, a front end plate and a rear end plate installed on the bottom plate, and slide grooves are respectively provided on the inner sides of the front end plate and the rear end plate, and two pairs of sliders are respectively installed in the slide grooves, and each pair of the sliders is connected by a connecting rod, and a positioning hole is provided on the connecting rod, and a positioning bolt that passes through the positioning hole and is connected to the bottom plate is installed in the positioning hole, and the template installation mechanism fixing seat is installed on the connecting rod; The middle parts of the upper ends of the front end plate and the rear end plate are connected by a connecting beam, the screw is fixed to the middle part of the connecting beam, the screw sleeve of the prefabricated rock mass container is fixed to the screw by an adjusting wheel, and the screw sleeve is controlled by the adjusting wheel to move up and down; A template base positioning screw is arranged in parallel on one side of the connecting rod, and both ends of the template base positioning screw are fixed on the sliding block, and the template mounting mechanism fixing seat is installed on the positioning screw and the connecting rod through the mounting holes opened thereon; A gear matched with the positioning screw is provided in the template installation mechanism fixing seat, the gear is meshed with an adjusting gear arranged in parallel, the axle of the adjusting gear extends out of the template installation mechanism fixing seat and is connected to an adjusting handle, and the template installation mechanism fixing seat is controlled to move on the positioning screw by rotating the adjusting handle; A template installation mechanism fixed seat displacement adjustment scale is provided on one side of the positioning screw on the base; and a slider displacement scale is provided on the front end plate of the base.

2. The experimental method for prefabricating three-dimensional cracks in rock mass using similar materials according to claim 1, characterized in that: A volute spring is arranged on the template installation rod, and the end of the flexible template is connected to the outer end of the volute spring.

3. The experimental method for prefabricating three-dimensional cracks in rock mass using similar materials according to claim 1, characterized in that: A raised gear shaft is provided on the angle adjustment disk at its axial center position, the gear of the fine adjustment handle is installed on the gear shaft, and a pair of raised secondary steps are symmetrically provided on both sides of the gear shaft as the gear shaft, wherein the large step is the gear shaft of the fine adjustment gear, and the small step is the gear shaft of the coarse adjustment gear.

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