Test system for directional and energy-gathered cracking of rock by using static cracking agent and implementation method

Abstract

The invention belongs to the technical field of rock cracking test devices, and discloses a static cracking agent oriented and energy-gathered rock cracking test system, which comprises a transverse loading mechanism I, a transverse loading mechanism II, a test piece and a deformation monitoring mechanism, the test piece is provided with a mounting hole, and the static cracking agent oriented and energy-gathered rock cracking test system further comprises an energy-gathered mechanism mounted in the mounting hole. According to the scheme, an operator puts the energy gathering mechanism into the mounting hole from bottom to top, the inner wall of the mounting hole can extrude the elastic ejector block, the elastic ejector block can abut against the inner wall of the mounting hole under the action of gravity and play a role in supporting the energy gathering mechanism, the top of the barrel is blocked by the top cover, and therefore radial fracturing of the mounting hole is achieved, and the energy gathering mechanism is fractured. And meanwhile, the condition of the bottom of the mounting hole is recorded through the adjusting assembly, so that the top coal or top plate fracturing mechanism and fracturing parameter optimization research under the conditions that the fracturing direction can be selectively selected according to the mining load direction, the axial punching force is changed into the radial fracturing force to improve the fracturing effect and the like in an underground coal mine is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of rock fracturing test equipment, and in particular is a static crushing agent directional and concentrated energy fracturing rock test system and an implementation method. Background Art

[0002] The principle of static crushing agent to crush rock or concrete is that when the main calcium oxide reacts with water, the solid phase volume and pore volume generated increase, which acts on the rock or concrete to generate expansion pressure, reaching the fracture strength of the rock or concrete, and crushing the rock or concrete.

[0003] Since static crushing agents do not produce toxic and harmful gases during use, and the reaction expansion process is adjustable and controllable, they have been widely used in coal mining in recent years to crush hard top coal and deal with hard roof suspension. However, when fracturing top coal or roof in coal mines, most of the drilling holes are upward holes. When static crushing agents are poured into upward holes, they are affected by gravity and are not dense, and are prone to punching. In addition, the surrounding rock in coal mines is affected by mining and will bear a large load. When the load direction is uncertain, the direction of the static crushing agent expansion and fracturing is difficult to determine, and the fracturing effect is poor.

[0004] In order to effectively improve the effect of static crushing agents in fracturing top coal or roof in coal mines and make the expansion of coal rock cracks controllable, it is also necessary to fully study the method of injecting static crushing agents into upward holes and the static crushing mechanism of upward holes, including: how to control the fracturing direction, how to convert the axial force of punching holes into radial force for fracturing coal and rock, and improve the fracturing effect.

[0005] At present, the mechanism of rock or concrete cracking by static crushers is mostly simplified to a mechanical model of a thin plate circular hole without lateral force subjected to uniformly distributed load. The indoor experimental system is only composed of a cubic rock or concrete specimen with a prefabricated circular hole, a strain gauge, a strain gauge, etc., which can realize the research on the mechanism of rock or concrete cracking under different static crusher water-cement ratios, different borehole diameters, and different borehole spacings. However, it is difficult to meet the research on the mechanism of cracking top coal or top plate and the optimization of cracking parameters under the conditions of selective cracking direction according to the direction of mining load, changing axial punching force into radial cracking force to improve the cracking effect, etc. In this regard, the present invention provides a static crusher directional and concentrated energy cracking rock test system and implementation method. Summary of the invention

[0006] In order to solve the problems raised in the above-mentioned background technology, the present invention provides a static crusher directional and concentrated energy fracturing rock test system and implementation method, so as to solve the problem that the existing methods are difficult to meet the requirements of the research on the mechanism of fracturing top coal or roof and the optimization of fracturing parameters under the conditions that the selective fracturing direction can be selected according to the direction of mining load, the axial punching force can be changed into radial fracturing force to improve the fracturing effect, etc.

[0007] To achieve the above object, the present invention provides the following technical solutions: a static crusher directional and energy-gathering rock fracture test system, comprising a first lateral loading mechanism, a second lateral loading mechanism, a test piece and a deformation monitoring mechanism, wherein the test piece is provided with a mounting hole, and further comprising: an energy-gathering mechanism, which is mounted inside the mounting hole;

[0008] The lateral loading mechanism 1 comprises a base, a pressurizing cylinder 1 and a support 1 are respectively installed on the top of the base in symmetrical directions, the test piece is placed between the support 1 and the output end of the pressurizing cylinder 1, and a pad 1 is installed at the output end of the pressurizing cylinder 1 to abut against one side of the test piece;

[0009] The second transverse loading mechanism comprises a second pressurizing cylinder and a second support symmetrically mounted on the top of the base, and a second cushion block abutting against the front of the test piece is fixedly connected to the output end of the second pressurizing cylinder;

[0010] The energy gathering mechanism comprises an energy gathering component, a cover component is installed on the top of the energy gathering component, transverse slits are symmetrically opened on the energy gathering component, annular slits are symmetrically opened on the energy gathering component at both ends of the transverse slits, and a cylindrical non-woven fabric is placed inside the energy gathering component; the energy gathering component comprises a cylinder;

[0011] The cover assembly comprises a top cover which is threadedly connected to the top end of the cylinder, and an elastic top block is elastically supported in a circumferential array on the top cover.

[0012] Preferably, one end of the elastic top block located outside the top cover is movably connected with a rubber plate.

[0013] Preferably, the energy gathering component further comprises a hollow column fixedly connected to the inside of the energy gathering component, the top end of the hollow column can extend to the inside of the top cover, a connecting rod is elastically connected to the inside of the cylinder, and the connecting rod has an upward trend, and the top of the connecting rod extends into the hollow column and is fixedly connected with a connecting buckle;

[0014] The cover assembly comprises a clamping block which is fixedly connected to the bottom of the top cover and can be clamped with a connecting buckle.

[0015] Preferably, the energy gathering assembly further comprises an annular member;

[0016] The cylinder is divided into three sections: upper, middle and lower. Two adjacent sections of the cylinder are fixedly connected by a ring. The ring is annular and has a V-shaped cross section in the front view direction.

[0017] The transverse slits and the circumferential slits are both provided in the middle section of the cylinder;

[0018] The bottom of the cylinder is also provided with an adjusting assembly for forcing the three sections of the cylinder to move toward each other and for compressing the annular member.

[0019] Preferably, a convex shaft is fixedly connected to the bottom of the connecting rod, and a straight slot is also provided at the bottom of the connecting rod below the convex shaft;

[0020] The adjustment assembly comprises semi-arc blocks symmetrically and movably connected to the bottom of the cylinder, a rotating shaft is movably connected between the two semi-arc blocks, a lever is fixedly sleeved on the outside of the rotating shaft, and a guide groove movably sleeved on the outside of the convex shaft is provided on the lever;

[0021] Initially, both ends of the rotating shaft are movably sleeved on the bottom of the straight slot, and the distance between the top end of the guide slot and the rotating shaft is greater than the distance between the bottom end of the guide slot and the rotating shaft.

[0022] Preferably, the guide groove comprises a groove opening 1, a groove opening 2 and a positioning groove, and the top and bottom ends of the groove opening 2 are respectively connected with the bottom end of the groove opening 1 and the bottom end of the positioning groove;

[0023] Initially, the positioning groove is vertically arranged, the center of the second groove is concentric with the rotating shaft, and the distance between the top end of the first groove and the rotating shaft is greater than the distance between the bottom end of the first groove and the rotating shaft.

[0024] Preferably, the energy gathering assembly further comprises a sealing ring movably sleeved on the outside of the annular member;

[0025] The concave portion of the annular member is arranged to face the outside.

[0026] Preferably, the bottom of the cylinder is also symmetrically and movably connected to a supporting top rod; the bottom of the connecting rod is also fixedly connected to a corrugated strip, and in the initial state, the bottom end of the supporting top rod is located below the corrugated strip, and when the corrugated strip moves downward, it rotates in the horizontal direction and has an overlapping part with the bottom end of the supporting top rod.

[0027] A method for implementing a static breaker directional and energy-gathering rock cracking test system, using a static breaker directional and energy-gathering rock cracking test system, the implementation steps include:

[0028] S1. Put the static crusher into the cylinder and cover it with the top cover;

[0029] S2. Define the direction of the applied load on the artificial speckle surface of the specimen, insert the energy-gathering mechanism from the bottom of the base to the top into the mounting hole, support the energy-gathering mechanism as a whole in the mounting hole through the elastic force of the elastic top block, and apply pressure to the specimen by the pressure cylinder 2 and the pressure cylinder 1, respectively, and mark them as σ 1 , σ 2 , record σ 2 The angle between the direction and the transverse slit is α;

[0030] S3, start the second pressurized cylinder, wait for σ 1 When it reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; adjust the pad 1 and support 1 to the two σ2 The applied surface is in close contact, start the pressurized cylinder 1, and wait for σ 2 When it reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; record the time at this time as T1, start the adjustment component at the same time, and set the acquisition frequency to 100 frames / s; to avoid cracks at the installation hole, the test ends 5 minutes after the water vapor is released, record the time at this time as T2, and close the deformation monitoring mechanism; close the pressurizing cylinder 1 and the pressurizing cylinder 2 in turn, release the pressure, adjust the cushion block 1 and the cushion block 2, take out the test piece, and record the test;

[0031] S4. Sort the speckle images of the specimen collected between T1 and T2 by comparing the time, select the speckle image at the initial moment as the reference undeformed image, use the digital image correlation method to process the subsequent images by computer, obtain the full-field deformation of the specimen surface between T1 and T2, and determine the starting time T4 of the concentrated deformation around the installation hole under the action of the energy-gathering mechanism by comparison, and calculate the duration ΔT; take the center of the installation hole as the starting point, measure the length L of the deformation concentration area when it is stable, and determine the consistency between the extension direction of the deformation concentration area and the directional cracking direction of the energy-gathering mechanism; and use the virtual extensometer function in the digital image correlation method, take the center of the installation hole as the starting point, and arrange 3-5 virtual extensometers at equal intervals in the deformation concentration area to calculate the change of the crack degree d of the deformation concentration crack over time

[0032] S5, repeat S1, S2, S3 and S4, respectively set the transverse cut in the energy-gathering mechanism and the σ of the specimen 2 The applied surface is 15°, 30° and 45° to obtain the bidirectional load σ 1 =σ 2 =4MPa, α = 0°, 15°, 30° or 45°, and the consistency of T4-T2, ΔT, L, d, crack opening direction and directional cracking direction under different α values ​​are compared to obtain the optimal α value.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] In the above scheme, the operator places the energy-gathering mechanism into the installation hole from bottom to top, and the inner wall of the installation hole will squeeze the elastic top block. When the energy-gathering mechanism stops being pushed, the elastic top block will abut against the inner wall of the installation hole under the action of gravity and play a supporting role for the energy-gathering mechanism. Since the top of the cylinder is blocked by the top cover, the static crushing agent will expand through the transverse slit and the annular slit at this time, thereby realizing radial fracturing of the installation hole. At the same time, the situation at the bottom of the installation hole is recorded by adjusting the component, so as to facilitate the optimization research of the mechanism and fracturing parameters of the top coal or roof under the conditions of selective fracturing direction according to the mining load direction, changing the axial punching force into the radial fracturing force to improve the fracturing effect, etc.

[0035] The above scheme, by putting the top cover on the cylinder, will also make the block and the connecting buckle buckle, then turn the lever to make it rotate, so that the convex shaft moves along the slot and drives the convex shaft downward, so that the connecting rod pulls the block and the top cover downward through the connecting buckle. Since the top cover is fixed in the vertical direction by the elastic top block and cannot go down, relatively, at this time, the three sections of the cylinder have a tendency to move upward and approach each other, and finally the two groups of annular parts will be compressed, so that the static crushing agent completely fills the cylinder, thereby preventing the static crushing agent from expanding along the axial direction of the installation hole and reducing the fracturing effect on the rock;

[0036] In the above scheme, the annular member is compressed and squeezed to squeeze the sealing ring so that it expands and abuts against the inner wall of the mounting hole, thereby forming a closed space inside the mounting hole to ensure that the static crushing agent cannot extend along the axial direction of the mounting hole, thereby enabling the static crushing agent to better achieve a cracking effect on the specimen along the radial direction of the inner wall of the mounting hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0038] Figure 2 It is a bottom view structural schematic diagram of the present invention;

[0039] Figure 3 It is a structural schematic diagram of the energy gathering mechanism of the present invention;

[0040] Figure 4 It is a front cross-sectional structural schematic diagram of the energy gathering mechanism of the present invention;

[0041] Figure 5 for Figure 4 The enlarged view of point A in the middle;

[0042] Figure 6 for Figure 4 The enlarged view of point B in the middle;

[0043] Figure 7 It is a structural schematic diagram of the regulating assembly of the present invention;

[0044] Figure 8 It is a bottom sectional plan view of the cylinder of the present invention;

[0045] Figure 9 It is a schematic diagram of the side cross-sectional structure of the energy gathering mechanism of the present invention;

[0046] Figure 10 for Figure 9 Enlarged view of point C in the middle;

[0047] Figure 11 It is a schematic diagram of the structure of the corrugated strip of the present invention;

[0048] Figure 12Schematic diagram of the stress direction and directional cracking direction of the specimen.

[0049] In the figure: 1, transverse loading mechanism 1; 11, base; 12, pressurized oil cylinder 1; 13, cushion block 1; 14, support 1; 2, transverse loading mechanism 2; 21, pressurized oil cylinder 2; 22, cushion block 2; 23, support 2; 3, test piece; 31, mounting hole; 4, energy gathering mechanism; 41, energy gathering assembly; 411, cylinder; 412, ring member; 413, sealing ring; 414, hollow column; 415, connecting rod; 4151, connecting buckle; 4152, convex shaft ; 4153, straight slot; 4154, corrugated strip; 42, cover assembly; 421, top cover; 422, block; 423, elastic top block; 4231, rubber sheet; 43, transverse slit; 44, circumferential slit; 45, tubular non-woven fabric; 5, adjustment assembly; 51, semi-arc block; 52, rotating shaft; 53, lever; 54, guide groove; 541, slot one; 542, slot two; 543, positioning groove; 6, deformation monitoring mechanism; 7, support top rod. DETAILED DESCRIPTION

[0050] 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] like Figures 1 to 12 As shown, the present invention provides a static crushing agent directional and energy-gathering fracturing rock test system, comprising a lateral loading mechanism 1, a lateral loading mechanism 2, a test piece 3 and a deformation monitoring mechanism 6, wherein the test piece 3 is provided with a mounting hole 31, and an energy-gathering mechanism 4 is installed inside the mounting hole 31, and further comprising: the lateral loading mechanism 1 comprises a base 11, and a pressurizing cylinder 12 and a support 14 are respectively installed on the top of the base 11 in symmetrical directions, and the test piece 3 is placed between the support 14 and the output end of the pressurizing cylinder 12, and a pad 13 is installed on the output end of the pressurizing cylinder 12 to abut against one side of the test piece 3;

[0052] The lateral loading mechanism 2 comprises a pressurizing cylinder 21 and a support 23 which are symmetrically mounted on the top of the base 11, and a pad 22 which abuts against the front of the test piece 3 is fixedly connected to the output end of the pressurizing cylinder 21;

[0053] The energy gathering mechanism 4 includes an energy gathering component 41, a cover component 42 is installed on the top of the energy gathering component 41, transverse slits 43 are symmetrically opened on the energy gathering component 41, and annular slits 44 located at both ends of the transverse slits 43 are also symmetrically opened on the energy gathering component 41, and a cylindrical non-woven fabric 45 is also placed inside the energy gathering component 41; the energy gathering component 41 includes a cylinder 411; the cover component 42 includes a top cover 421 threadedly connected to the top of the cylinder 411, and an elastic top block 423 is circumferentially arrayed and elastically supported on the top cover 421; one end of the elastic top block 423 located outside the top cover 421 is movably clamped with a rubber plate 4231;

[0054] By adopting the above scheme, the operator places the energy-gathering mechanism 4 into the mounting hole 31 from bottom to top, and the inner wall of the mounting hole 31 will squeeze the elastic top block 423. When the energy-gathering mechanism 4 stops being pushed, the elastic top block 423 will abut against the inner wall of the mounting hole 31 under the action of gravity and play a supporting role for the energy-gathering mechanism 4. Since the top of the cylinder 411 is blocked by the top cover 421, the static crushing agent will expand through the transverse slit 43 and the annular slit 44 at this time, thereby realizing radial fracturing of the mounting hole 31. At the same time, the situation at the bottom of the mounting hole 31 is recorded by the adjusting component 5, so as to facilitate the optimization research on the mechanism of fracturing top coal or roof and fracturing parameters under the conditions that the fracturing direction can be selected according to the direction of mining load, the axial punching force is changed to the radial fracturing force to improve the fracturing effect, etc.

[0055] like Figures 1 - 12 As shown, the energy gathering component 41 further includes a hollow column 414 fixedly connected to the inside of the energy gathering component 41, the top of the hollow column 414 can extend to the inside of the top cover 421, the cylinder 411 is elastically connected to a connecting rod 415, and the connecting rod 415 has an upward trend, and the top of the connecting rod 415 extends into the hollow column 414 and is fixedly connected to a connecting buckle 4151;

[0056] The cover assembly 42 includes a block 422 fixedly connected to the bottom of the top cover 421 and capable of being engaged with the connecting buckle 4151; the energy gathering assembly 41 also includes a ring 412; the cylinder 411 is divided into three sections, namely, upper, middle and lower sections, and the cylinders 411 of two adjacent sections are fixedly connected by the ring 412, and the ring 412 is annular, and its cross section in the front view direction is "V"-shaped; the transverse slit 43 and the annular slit 44 are both opened in the middle section of the cylinder 411;

[0057] The bottom of the cylinder 411 is also provided with an adjustment assembly 5 for forcing the three sections of the cylinder 411 to move toward each other and for compressing the annular member 412;

[0058] A convex shaft 4152 is fixedly connected to the bottom of the connecting rod 415, and a straight slot 4153 is also formed at the bottom of the connecting rod 415 below the convex shaft 4152;

[0059] The adjustment assembly 5 includes a semi-arc block 51 symmetrically and movably connected to the bottom of the cylinder 411, a rotating shaft 52 is movably connected between the two semi-arc blocks 51, a lever 53 is fixedly sleeved on the outside of the rotating shaft 52, and a guide groove 54 movably sleeved on the outside of the convex shaft 4152 is formed on the lever 53;

[0060] Initially, both ends of the rotating shaft 52 are still movably sleeved on the bottom of the straight slot 4153, and the distance between the top end of the guide slot 54 and the rotating shaft 52 is greater than the distance between the bottom end of the guide slot 54 and the rotating shaft 52;

[0061] The guide groove 54 includes a groove 1 541, a groove 2 542 and a positioning groove 543. The top and bottom of the groove 2 542 are connected to the bottom of the groove 1 541 and the bottom of the positioning groove 543 respectively.

[0062] Initially, the positioning groove 543 is vertically arranged, the center of the second groove 542 is concentric with the rotation shaft 52, and the distance between the top end of the groove 541 and the rotation shaft 52 is greater than the distance between the bottom end of the groove 541 and the rotation shaft 52;

[0063] By adopting the above scheme, by covering the top cover 421 on the cylinder 411, the block 422 will be engaged with the connecting buckle 4151, and then the lever 53 is turned to rotate, so that the convex shaft 4152 moves along the slot 1 541 and drives the convex shaft 4152 downward, so that the connecting rod 415 pulls the block 422 and the top cover 421 downward through the connecting buckle 4151. Since the top cover 421 is fixed in the vertical direction by the elastic top block 423 and cannot move downward, relatively, at this time, the three sections of the cylinder 411 have a tendency to move upward and approach each other, and finally the two groups of annular members 412 will be compressed, so that the static crushing agent completely fills the cylinder 411, thereby preventing the static crushing agent from expanding along the axial direction of the mounting hole 31 and reducing the fracturing effect on the rock.

[0064] like Figures 3 - 5 and Figure 9 As shown, the energy gathering assembly 41 further includes a sealing ring 413 movably sleeved on the outside of the annular member 412; the concave portion of the annular member 412 is arranged to face the outside;

[0065] By adopting the above scheme, the annular member 412 is compressed and squeezed to squeeze the sealing ring 413 to expand it and abut against the inner wall of the mounting hole 31, thereby forming a closed space inside the mounting hole 31 to ensure that the static crushing agent cannot extend along the axial direction of the mounting hole 31, thereby enabling the static crushing agent to better achieve a fracturing effect on the specimen 3 along the radial direction of the inner wall of the mounting hole 31.

[0066] like Figure 3 , Figure 6 , Figure 7 and Figures 9 - 11As shown, the bottom of the cylinder 411 is also symmetrically and movably connected to the supporting top rod 7; the bottom of the connecting rod 415 is also fixedly connected to the corrugated strip 4154, and the bottom end of the supporting top rod 7 is located below the corrugated strip 4154 in the initial state. When the corrugated strip 4154 moves downward, it overlaps with the bottom end of the supporting top rod 7 when it rotates in the horizontal direction;

[0067] By adopting the above scheme, when the convex shaft 4152 moves into the positioning groove 543, the connecting rod 415 will move downward, which will drive the corrugated strip 4154 to move downward and be at the same height as the bottom end of the supporting top rod 7. Then, the adjusting component 5 is rotated in the circumferential direction of the cylinder 411, which will drive the connecting rod 415 to rotate circumferentially and make the corrugated strip 4154 squeeze the supporting top rod 7, so that the top end of the supporting top rod 7 is squeezed against the inner wall of the mounting hole 31, and the energy gathering mechanism 4 is fixed as a whole in the mounting hole 31 by cooperating with the elastic top block 423.

[0068] The working principle and use process of the present invention:

[0069] Put the static crushing agent into the cylinder 411 and cover it with the top cover 421;

[0070] Determine the load application direction of the artificial speckle surface of the specimen 3, insert the energy-gathering mechanism 4 from the bottom of the base 11 into the mounting hole 31 from bottom to top, and support the energy-gathering mechanism 4 as a whole in the mounting hole 31 through the elastic force of the elastic top block 423, and apply pressure to the specimen 3 by the pressurized oil cylinder 21 and the pressurized oil cylinder 1 12, respectively, and mark them as σ 1 , σ 2 , record σ 2 The angle between the direction and the transverse slit 43 is α;

[0071] Start the pressurized oil cylinder 21 and wait for 1 When it reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; adjust the pad 13 and the support 14 to the two σ of the specimen 3 respectively. 2 The applied surface is in close contact, and the pressurized oil cylinder 12 is started. 2 When the load reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; record the time at this time as T1, start the adjustment component 5 at the same time, and set the acquisition frequency to 100 frames / s; to avoid cracks at the mounting hole 31, the test ends 5 minutes after the water vapor is released, record the time at this time as T2, and close the deformation monitoring mechanism 6; close the pressurizing cylinder 1 12 and the pressurizing cylinder 2 21 in turn, release the pressure, adjust the cushion block 13 and the cushion block 22, take out the test piece 3, and record the test;

[0072] Subsequently, the speckle images of the specimen 3 collected between T1 and T2 were sorted and processed according to the time, and the speckle images at the initial moment were selected as the reference undeformed images. The subsequent images were processed by computer using the digital image correlation method to obtain the full-field deformation of the surface of the specimen 3 between T1 and T2, and the starting time T4 of the concentrated deformation around the mounting hole 31 under the action of the energy-gathering mechanism 4 was determined by comparison, and the duration ΔT was calculated; the center of the mounting hole 31 was taken as the starting point, the length L of the deformation concentration area was measured when it was stable, and the consistency of the extension direction of the deformation concentration area and the directional cracking direction of the energy-gathering mechanism 4 was determined; and the virtual extensometer function in the digital image correlation method was used, and the center of the mounting hole 31 was taken as the starting point, and 3-5 virtual extensometers were arranged at equal intervals in the deformation concentration area, and the cracking degree d of the cracks in the deformation concentration was calculated. Changes over time;

[0073] Finally, repeat the above steps to set the transverse slit 43 in the energy focusing mechanism 4 and the σ of the specimen 3 respectively. 2 The applied surface is 15°, 30° and 45° to obtain the bidirectional load σ 1 =σ 2 =4MPa, α = 0°, 15°, 30° or 45°, and the test results of static crusher directional energy-aggregate fracturing rock. The T4-T2, ΔT, L, d, crack opening direction and directional fracturing direction consistency under different α values ​​were compared to obtain the optimal α value.

[0074] When the operator puts the energy-gathering mechanism 4 into the mounting hole 31 from bottom to top, the inner wall of the mounting hole 31 will squeeze the elastic top block 423. When the energy-gathering mechanism 4 stops being pushed, the elastic top block 423 will abut against the inner wall of the mounting hole 31 under the action of gravity and play a supporting role for the energy-gathering mechanism 4. Since the top of the cylinder 411 is blocked by the top cover 421, the static crushing agent will expand through the transverse slit 43 and the annular slit 44 at this time, thereby achieving radial fracturing of the mounting hole 31.

[0075] By covering the top cover 421 on the cylinder 411, the block 422 is also engaged with the connecting buckle 4151, and then the lever 53 is toggled to rotate, so that the convex shaft 4152 moves along the slot 1 541 and drives the convex shaft 4152 downward, so that the connecting rod 415 pulls the block 422 and the top cover 421 downward through the connecting buckle 4151. Since the top cover 421 is fixed in the vertical direction by the elastic top block 423 and cannot move downward, relatively, at this time, the three sections of the cylinder 411 have a tendency to move upward and approach each other, and finally the two groups of annular members 412 will be compressed, so that the static crushing agent completely fills the cylinder 411;

[0076] When the two groups of annular members 412 are compressed, the sealing ring 413 is squeezed to expand and abut against the inner wall of the mounting hole 31, thereby forming a closed space inside the mounting hole 31 to ensure that the static crushing agent cannot extend along the axial direction of the mounting hole 31, thereby enabling the static crushing agent to better achieve a fracturing effect on the specimen 3 along the radial direction of the inner wall of the mounting hole 31.

[0077] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0078] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A static crushing agent directional and energy-gathering rock fracture test system, comprising a transverse loading mechanism (1), a transverse loading mechanism (2), a test piece (3) and a deformation monitoring mechanism (6), wherein a mounting hole (31) is provided on the test piece (3), and the system is characterized in that: Also includes: An energy gathering mechanism (4) installed inside the installation hole (31); The transverse loading mechanism (1) comprises a base (11), a pressurizing cylinder (12) and a support (14) are respectively installed on the top of the base (11) in symmetrical directions, the test piece (3) is placed between the support (14) and the output end of the pressurizing cylinder (12), and a cushion block (13) is installed on the output end of the pressurizing cylinder (12) to abut against one side of the test piece (3); The second transverse loading mechanism (2) comprises a second pressurizing cylinder (21) and a second support (23) symmetrically mounted on the top of the base (11); the output end of the second pressurizing cylinder (21) is fixedly connected with a second cushion block (22) abutting against the front of the test piece (3); The energy gathering mechanism (4) comprises an energy gathering component (41), a cover component (42) is installed on the top of the energy gathering component (41), transverse slits (43) are symmetrically provided on the energy gathering component (41), annular slits (44) are symmetrically provided on the energy gathering component (41) and located at both ends of the transverse slits (43), and a cylindrical non-woven fabric (45) is also placed inside the energy gathering component (41); The energy gathering assembly (41) comprises a cylinder (411); The cover assembly (42) comprises a top cover (421) threadedly connected to the top end of the cylinder (411), and elastic top blocks (423) are arranged in a circumferential array and elastically supported on the top cover (421).

2. The static crusher directional and energy-gathering rock fracture test system according to claim 1 is characterized by: One end of the elastic top block (423) located outside the top cover (421) is movably clamped with a rubber plate (4231).

3. The static crusher directional and concentrated energy fracturing rock test system and implementation method according to claim 2 is characterized by: The energy gathering component (41) further comprises a hollow column (414) fixedly connected to the inside of the energy gathering component (41), the top end of the hollow column (414) can extend to the inside of the top cover (421), the inside of the cylinder (411) is elastically connected to a connecting rod (415), and the connecting rod (415) has an upward trend, and the top of the connecting rod (415) extends into the hollow column (414) and is fixedly connected to a connecting buckle (4151); The cover body assembly (42) comprises a clamping block (422) fixedly connected to the bottom of the top cover (421) and capable of being clamped with a connecting buckle (4151).

4. The static crusher directional and energy-gathering rock fracture test system according to claim 3 is characterized by: The energy gathering assembly (41) further includes an annular member (412); The cylinder (411) is divided into three sections: upper, middle and lower. Two adjacent sections of the cylinder (411) are fixedly connected by a ring member (412). The ring member (412) is ring-shaped, and its cross section in the front view direction is "V"-shaped. The transverse slit (43) and the annular slit (44) are both formed in the middle section of the cylinder (411); The bottom of the cylinder (411) is also provided with an adjustment component (5) for forcing the three sections of the cylinder (411) to move toward each other and for compressing the annular member (412).

5. The static crusher directional and energy-gathering rock fracture test system according to claim 4 is characterized by: A convex shaft (4152) is fixedly connected to the bottom of the connecting rod (415), and a straight slot (4153) is also formed at the bottom of the connecting rod (415) and is located below the convex shaft (4152); The adjustment assembly (5) comprises semi-arc blocks (51) symmetrically and movably connected to the bottom of the cylinder (411); a rotating shaft (52) is movably connected between the two semi-arc blocks (51); a lever (53) is fixedly sleeved on the outside of the rotating shaft (52); and a guide groove (54) movably sleeved on the outside of the convex shaft (4152) is formed on the lever (53); Initially, both ends of the rotating shaft (52) are movably sleeved on the bottom of the straight slot (4153), and the distance between the top end of the guide groove (54) and the rotating shaft (52) is greater than the distance between the bottom end of the guide groove (54) and the rotating shaft (52).

6. The static crusher directional and energy-gathering rock fracture test system according to claim 5 is characterized by: The guide groove (54) comprises a groove opening (541), a groove opening (542) and a positioning groove (543), and the top and bottom ends of the groove opening (542) are respectively connected to the bottom end of the groove opening (541) and the bottom end of the positioning groove (543); Initially, the positioning groove (543) is vertically arranged, the center of the second groove (542) is concentric with the rotating shaft (52), and the distance between the top end of the first groove (541) and the rotating shaft (52) is greater than the distance between the bottom end and the rotating shaft (52).

7. The static crusher directional and energy-gathering rock fracture test system according to claim 6 is characterized by: The energy gathering component (41) further comprises a sealing ring (413) movably sleeved on the outside of the annular member (412); The recessed portion of the annular member (412) is arranged to face the outside.

8. The static crusher directional and energy-gathering rock fracture test system according to claim 7 is characterized by: The bottom of the cylinder (411) is also symmetrically and movably connected to a supporting top rod (7); The bottom of the connecting rod (415) is also fixedly connected with a corrugated strip (4154). In the initial state, the bottom end of the supporting top rod (7) is located below the corrugated strip (4154). When the corrugated strip (4154) moves downward, it rotates in the horizontal direction and overlaps with the bottom end of the supporting top rod (7).

9. A method for implementing a static crushing agent directional and concentrated energy cracking rock test system, using the static crushing agent directional and concentrated energy cracking rock test system as claimed in claim 8, characterized in that: S1, placing a static crushing agent into the cylinder (411) and covering it with a top cover (421); S2, define the direction of the applied load on the artificial speckle surface of the specimen (3), insert the energy-gathering mechanism (4) from the bottom of the base (11) into the mounting hole (31) from bottom to top, support the energy-gathering mechanism (4) as a whole in the mounting hole (31) by the elastic force of the elastic top block (423), apply pressure to the specimen (3) by the pressure cylinder 2 (21) and the pressure cylinder 1 (12), and mark them as σ1 and σ2 respectively, and record the angle between the σ2 direction and the transverse slit (43) as α; S3, start the pressurizing cylinder 2 (21), and when σ1 reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; adjust the pad 1 (13) and the support 1 (14) to be in close contact with the two σ2 application surfaces of the test piece (3), start the pressurizing cylinder 1 (12), and when σ2 reaches 4MPa, stop pressurizing, close the valve, and keep the load constant; record the time at this time as T1, and start the adjustment component (5) at the same time, and set the acquisition frequency to 100 frames / s; in order to avoid cracks at the mounting hole (31), the test end time is 5 minutes after the water vapor is released, and the time at this time is recorded as T2, and the deformation monitoring mechanism (6) is closed; the pressurizing cylinder 1 (12) and the pressurizing cylinder 2 (21) are closed in turn, the pressure is released, the pad 1 (13) and the pad 2 (22) are adjusted, the test piece (3) is taken out, and the test is recorded; S4, the speckle images of the specimen (3) collected between T1 and T2 are sorted and processed according to time, the speckle image at the initial moment is selected as the reference undeformed image, and the subsequent images are processed by computer using the digital image correlation method to obtain the full-field deformation of the surface of the specimen (3) between T1 and T2, and the starting time T4 of the concentrated deformation around the mounting hole (31) under the action of the energy-gathering mechanism (4) is determined by comparison, and the duration ΔT is calculated; the center of the mounting hole (31) is used as the starting point, the length L of the deformation concentration area is measured when it is stable, and the consistency of the extension direction of the deformation concentration area and the directional cracking direction of the energy-gathering mechanism (4) is determined; and the virtual extensometer function in the digital image correlation method is used, the center of the mounting hole (31) is used as the starting point, 3-5 virtual extensometers are arranged at equal intervals in the deformation concentration area, and the crack degree d of the crack opening in the deformation concentration is calculated. Changes over time. S5. Repeat S1, S2, S3 and S4, respectively set the transverse cut (43) in the energy-gathering mechanism (4) to the σ2 application surface of the specimen (3) at 15°, 30° and 45°, obtain the test results of static crusher directional energy-gathering fracturing rock under bidirectional load σ1=σ2=4MPa and α=0°, 15°, 30° or 45°, compare T4-T2, ΔT, L, d, crack opening direction and directional fracturing direction consistency under different α values, and obtain the optimal α value.

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