Grouting cylinder, device and method for indoor simulation grouting test of fault and fracture zone rock mass

Abstract

The invention discloses a fault and fracture zone rock mass indoor simulation grouting test grouting cylinder, device and method, and belongs to the technical field of rock sample grouting tests.The device comprises the grouting cylinder, the method is achieved based on the grouting cylinder, the grouting cylinder comprises a cylinder body, and the top end of the cylinder body is provided with a top end plate used for sealing the top end; a bottom end plate used for sealing the bottom end is arranged at the bottom end of the cylinder body, and a lining layer is adhered to the inner wall of the cylinder body through a hot melt adhesive; the device further comprises a plate-ring-shaped pressing ring, and the shape of the pressing ring is matched with an inner hole in the upper end of the barrel body. The device further comprises a pressing device connected to the inner wall of the barrel, and the pressing device is used for providing pressure towards the bottom end of the barrel for the pressing ring. According to the technical scheme, the accuracy of test results can be effectively guaranteed, and the requirement for test auxiliary materials is lowered.

Description

Technical Field

[0001] The invention relates to the technical field of rock sample grouting test, and in particular to a grouting tube, a device and a method for indoor simulated grouting test of fault and fracture zone rock mass. Background Art

[0002] Grouting is often used to treat faults and broken zones in dam foundations. Grouting methods include ordinary cement grouting, ultrafine cement (or wet-ground fine cement) grouting and chemical grouting, as well as first using cement slurry to seal large defects and then using chemical grouting materials for grouting, i.e. cement-chemical composite grouting technology. Among them, chemical grouting is a technology for strengthening foundations, waterproofing and plugging leaks, and strengthening concrete defects by preparing chemical materials into solutions and injecting them into strata or cracks using pressure equipment such as chemical grouting pumps to make them penetrate, diffuse, gel or solidify, so as to increase strata strength, reduce strata permeability, prevent strata deformation, and repair cracks in concrete buildings.

[0003] In infrastructure foundation construction, the grouting material commonly used for chemical grouting is epoxy resin chemical grouting material. There are many common grouting materials, such as grouting materials of models HK-G-2-2, PSI-501, TK, YDS, RH-1, and CW511 produced by different manufacturers. Before the formal on-site grouting construction, indoor simulated grouting tests are carried out on the original rock samples retrieved from different fault locations on site. The slurry filling and infiltration conditions of different rock samples in the fault fracture zone under different grouting materials and different grouting pressures, especially the mudstone body, can be studied and obtained, which is of great significance to the subsequent selection of grouting materials and construction process design.

[0004] In the prior art, the simulated grouting device, such as the solution provided in the patent document with patent application number CN202320882642.3, includes a device cylinder, a top end plate, a bottom end plate, etc. The test process includes: rock sampling, simulated grouting, sampling and analysis, etc. In the rock sampling process, first, a loose rock sample can be laid at the bottom of the device cylinder, and then the rock sample to be grouted is placed in the device cylinder, and a grouting pipe is inserted into the rock sample from the outside of the device cylinder, and then epoxy cement is used to fill the cavity between the rock sample and the device cylinder. After the epoxy cement is cured, the space on the upper part of the device cylinder is densely filled with fine sand, and then the top end plate, grouting pipe, connecting valve, etc. are installed to carry out subsequent grouting work. The above epoxy cement filled in the cavity is used to constrain the grouting material to ensure that the slurry penetrates from the inside of the rock sample during grouting, so as to simulate the confining pressure of the infiltration path and improve the value of the test results for on-site construction.

[0005] Indoor grouting tests can effectively verify the permeability of grouting materials to the grouting medium, explore the treatment effect of grouting materials on the grouting medium under different environments, provide guidance for the selection of chemical grouting materials, grouting pressure, injection volume and other grouting parameters in construction, and further optimize the grouting test plan, which is of great significance to improving and ensuring construction quality. Summary of the invention

[0006] In order to optimize the grouting test scheme proposed above, the present invention provides a grouting tube, device and method for indoor simulated grouting test of fault and fracture zone rock mass. This technical scheme can effectively ensure the accuracy of test results and reduce the requirements for test auxiliary materials.

[0007] The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass provided by the present invention solves the problem through the following technical points: the grouting tube for indoor simulated grouting test of fault and fracture zone rock mass comprises a cylinder, the top end plate for sealing the top end is arranged at the top of the cylinder, the bottom end plate for sealing the bottom end is arranged at the bottom of the cylinder, and an inner lining layer is attached to the inner wall of the cylinder by hot melt adhesive;

[0008] It also includes a plate-ring-shaped pressure ring, the shape of which is adapted to the inner hole at the upper end of the cylinder: after the rock mass to be grouted is installed in the cylinder and the gap between the rock mass and the cylinder is sealed with epoxy glue, the pressure ring can be placed into the cylinder from the top of the cylinder and supported on the epoxy glue, and the contact surface between the pressure ring and the epoxy glue is located at the edge of the epoxy glue and extends along the circumferential direction of the cylinder;

[0009] It also includes a pressing device connected to the inner wall of the cylinder, and the pressing device is used to provide pressure for the pressure ring toward the bottom end of the cylinder.

[0010] When using the grouting barrel to perform indoor simulated grouting of rock mass, the rock mass installation, epoxy mortar packaging between the rock mass and the barrel, grouting barrel packaging, and step-by-step increase of grouting pressure are completed in the corresponding order until the grouting under the highest pressure is completed (the relevant pressure is determined according to the rock sample and needs, for example, the single-stage pressure increase gradient adopts 0.2Mpa and the maximum pressure is 3Mpa). The epoxy mortar is used to limit the flow path of the grouting material, specifically to block the rock sample so that the grouting material enters the bottom of the barrel from the slurry inlet pipe on the bottom end plate, passes through the granular cushion layer on the bottom side of the barrel from bottom to top, enters the rock sample from the bottom of the rock sample, flows and diffuses in the rock sample, slurries out from the top of the rock sample and then passes through the granular cushion layer on the top side of the barrel, and then flows out from the first slurry outlet pipe, and flows out from the second slurry outlet pipe on the side of the barrel. The end of the second slurry outlet pipe is inserted into the insertion hole of the rock mass, and the outer periphery of the second slurry outlet pipe and the wall of the insertion hole are sealed with a sealing material. In the specific grouting, due to the pressure difference between the upper and lower ends of the rock mass, the bonding structure formed by the rock mass and the epoxy putty is supported by the top particle cushion under the grouting pressure, but the particle cushion cannot ensure complete compaction. Therefore, the bonding structure has the possibility of upward movement under the pressure difference, which becomes an inducing factor affecting the reliability of the epoxy putty sealing the cavity between the rock mass and the cylinder, such as cracking of the epoxy putty and separation of the epoxy putty from the cylinder. The specific reasons include: internal stress in the epoxy putty after curing, inappropriate proportion of the epoxy putty, inappropriate curing and curing process of the epoxy putty, inappropriate cleanliness and / or roughness of the inner wall of the cylinder, etc. In order to reduce this possibility, the present scheme provides the above technical scheme.

[0011] Specifically, before the rock mass is loaded into the cylinder, an inner lining layer is adhered to the inner wall of the cylinder by means of hot melt adhesive, and the inner surface of the inner lining layer is cleaned, dried, roughened, etc. to improve the surface quality of the surface for epoxy glue to bond, thereby reducing the possibility of separation of the epoxy glue from the inner lining layer during the grouting process and formation of a leakage channel for grouting material between the inner lining layer and the epoxy glue. After the test is completed, the rock sample is cored, and the attachments in the cylinder are cleaned, the inner lining layer can be torn off the cylinder by heating the hot melt adhesive, so that a new inner lining layer can be replaced in the next test. In this way, the inner wall of the cylinder is not used as The contact surface is in direct contact with the epoxy putty, so the cylinder will not be damaged during the roughness treatment. Therefore, this solution is beneficial to the long-term reliable pressure resistance of the cylinder. At the same time, compared with the inner wall of the cylinder as the contact surface in direct contact with the epoxy putty, from the residual angle of cleaning the inner wall of the cylinder in the last test, this solution can complete the cleaning after tearing off the inner lining layer. Therefore, this solution also has the characteristics of improving the convenience of the test. At the same time, compared with the steel cylinder, the inner lining layer can be made of plastic. When the inner wall of the inner lining layer is roughened to obtain a rough surface, the surface can be roughened by a simple grinding operation, which has the characteristics of simple operation. In summary, the inner lining layer provided by this solution is beneficial to the grouting test from the perspectives of test convenience, simplicity of operation, and tightness of the epoxy putty and the cylinder.

[0012] On the other hand, the present solution is to configure the cylinder with a pressure ring and a clamping device. The specific method of use is as follows: after the epoxy putty is poured and solidified, the pressure ring provides support for the top of the bonding structure with the assistance of the clamping device, and the pressure ring is inserted into the cylinder from the top end of the cylinder and supported on the epoxy putty. The contact surface between the pressure ring and the epoxy putty is located at the edge of the epoxy putty and extends along the circumferential direction of the cylinder. In this way, for the possible upward movement of the bonding structure under pressure, resulting in cracking and detachment of the bonding surface, the pressure ring reduces the displacement of the bonding structure by providing support for the bonding structure. This measure can effectively reduce the requirements for the bonding strength between the epoxy putty and the bonding surface, reduce the requirements for the flexibility of the epoxy putty, avoid the expansion of cracks that have already formed during the grouting process, etc. From the perspectives of epoxy putty material selection, proportioning, and maintenance, the purpose of reducing the requirements for the epoxy putty used in the test is achieved.

[0013] On the other hand, by arranging the clamping device on the cylinder, compared with connecting the clamping device to the top end plate, the process of the top end plate sealing the top of the cylinder can be avoided. Because the top end plate keeps moving downward, the position of the pressure ring is kept pressed downward by the clamping device, causing the epoxy resin structure to be destroyed under the pressure or the connection surface with the outer peripheral inner lining to be destroyed, thereby ensuring the reliability of the pressure ring.

[0014] In a specific embodiment, in order to ensure the pressure resistance of the cylinder during the grouting process, so that the pressure ring can act on the edge of the epoxy putty, and ensure the adhesion quality of the joint surface between the epoxy putty and the inner lining layer, the cylinder is a cylinder, the pressure ring is a circular ring, and the outer diameter of the pressure ring is equal to the inner diameter of the cylinder.

[0015] In a specific embodiment, in order to make the pressure ring and the combining structure have a larger contact area so as to exert the epoxy cement crack protection function, the inner diameter of the pressure ring is set to be consistent with the outer diameter of the rock coring barrel, and the difference between the inner diameter of the pressure ring and the outer diameter of the rock coring barrel is less than 3mm.

[0016] In a specific embodiment, as a technical solution with low cost for using an inner lining layer and easy roughening of the inner wall of the inner lining layer, the inner lining layer is a plastic plate layer with a smooth outer surface and a rough inner surface formed by roughening treatment, and the outer surface is bonded to the inner wall of the cylinder by hot melt adhesive. In this solution, since it is inconvenient to complete the exhaust and glue injection after the initial bonding between the outer surface of the inner lining layer and the cylinder, in order to facilitate the bonding quality of the hot melt adhesive, the outer surface is set to a smooth surface. For example, after applying the hot melt adhesive, subsequent pressing is performed to form a bonding connection relationship. For the inner surface, it is used as a bonding surface with epoxy putty during use. After roughening treatment, the bonding relationship formed by the rough surface can improve the bonding strength between the inner lining layer and the epoxy putty by subsequently injecting epoxy putty in the corresponding cavity.

[0017] In a specific embodiment, the inner lining layer is an integrally formed cylindrical structure or a cylindrical structure formed by overlapping or bonding the ends;

[0018] When the inner lining layer is an integrally formed cylindrical structure, the outer diameter of the inner lining layer is equal to the inner diameter of the cylinder body; when the inner lining layer is a cylindrical structure formed by overlapping or bonding the ends, hot melt adhesive is provided between each position of the outer surface of the inner lining layer and the cylinder body;

[0019] For the cylinder section with an inner lining layer on the cylinder body, the inner lining layer covers the entire surface of the cylinder section except for the slurry outlet holes. Two structural forms of the inner lining layer are provided above. When it is an integrally formed structure, that is, the inner lining layer itself is a cylindrical structure with an outer diameter consistent with the inner diameter of the cylinder body, and it is required to customize an inner lining layer of a specific size for a cylinder body of a specific size. When it is a cylindrical structure formed by overlapping or bonding the ends, the inner lining layer can be made of a coil. When it is used specifically, the plate material used as the inner lining layer is cut out according to the target cylinder body, and then rolled and pasted into the inside of the cylinder body. The coating of the hot melt adhesive and the coverage of the inner lining layer are used to ensure the reliability of the connection between the inner lining layer and the cylinder body, and to avoid the formation of a leakage channel for the grouting material between the cylinder body and the inner lining layer.

[0020] In a specific embodiment, the clamping device includes a plurality of clamping assemblies, the clamping assemblies include an internal threaded hole provided on the inner wall of the upper end of the barrel and a hexagon socket screw threadedly connected to the internal threaded hole, the internal threaded hole starts from the top of the barrel and extends along the height direction of the barrel, the internal threaded hole intersects with the inner wall of the barrel, and the lower end of the hexagon socket screw is exposed in the barrel;

[0021] The pressing components are arranged at intervals in the circumferential direction of the cylinder.

[0022] The above provides a specific implementation method of the clamping device, that is, an internal helical screw and an internal threaded hole form a clamping assembly that provides support for the top of the pressure ring. For example, even if the on-site sampling size of the rock sample is consistent, since cement mortar needs to be set on the outside of the rock sample for reinforcement and protection, it involves transportation and sample preparation before the test in the later stage, so the size of the rock sample used for the test is uncontrollable. In the above scheme, according to the position of the top of the rock sample in the cylinder, after it is placed in the cylinder below the pressure ring and supported on the combining structure, the internal hexagonal screw is rotated to move the internal hexagonal screw in the internal threaded hole to a position where the lower end can support the pressure ring. Multiple clamping assemblies are used to provide multi-point support for the pressure ring arranged at intervals along the circumferential direction. The intersection of the internal threaded hole and the inner wall of the cylinder means that the internal threaded hole is not a complete internal threaded hole. In this way, the internal hexagonal screw on the internal threaded hole can be partially exposed outside the internal threaded hole, so that the lower end of the internal hexagonal screw can be used to provide support for the pressure ring. By adopting this solution, before the hexagonal screw is installed in the internal threaded hole, the clamping assembly does not affect the internal space of the cylinder, which facilitates the implementation of rock placement and epoxy cement pouring. At the same time, the position of the hexagonal screw can be linearly adjusted according to the position of the top surface of the epoxy cement, and it has good adaptability to rocks of different heights.

[0023] In a specific embodiment, it also includes a thread protection layer, which is coated on the threads of the internal thread hole and the internal hexagonal screw, and the thread protection layer is a thread fastening glue or a thread sealant.

[0024] The purpose of setting up the above scheme is: after the grouting material is poured, it is generally necessary to obtain the grouting parameters through the bottom, top and side of the grouting barrel, so the grouting material will fill the internal space of the grouting barrel. With this scheme, the thread protective layer is coated after the hexagonal screw is moved down into place. When the residue in the grouting barrel is subsequently cleaned, the gap on the thread can be restored by tearing off the thread protective layer, thereby eliminating the tedious work of removing the residue in the thread and improving the convenience of using the grouting barrel.

[0025] In a specific embodiment, in order to make the thread protective layer easy to tear and separate from the thread in a large piece, the thread protective layer adopts a low-strength thread fastening glue or a thread sealant that is soft after curing.

[0026] In a specific embodiment, it also includes a second slurry outlet pipe arranged on the side wall of the cylinder, the side wall of the cylinder is provided with a slurry outlet hole which is a threaded hole, and the second slurry outlet pipe is connected to the slurry outlet hole through an external external thread;

[0027] It also includes a locking cap threadedly connected to the second pulp outlet pipe, wherein the locking cap is located on the second pulp outlet pipe outside the cylinder body;

[0028] It also includes a plugging screw threadedly connected to the second slurry outlet pipe, and the length of the plugging screw satisfies that the plugging screw can pass through the second slurry outlet pipe.

[0029] In the above scheme, for the overflow of grouting material on the side of the cylinder body, the second slurry outlet pipe is used as a conduit, and the second slurry outlet pipe is arranged to be threadedly connected to the slurry outlet hole, so as to facilitate the adjustment of the insertion depth of the second slurry outlet pipe into the rock sample according to needs. The locking cap is used to lock the second slurry outlet pipe after the insertion depth of the second slurry outlet pipe is adjusted. Specifically, the locking cap can be rotated to lock the second slurry outlet pipe by squeezing the locking cap and the outer wall of the cylinder body or squeezing the locking cap and the outer lining plate on the outer wall of the cylinder body. The plug screw is used to: After drilling an insertion hole for the rock sample inside the barrel using the slurry outlet hole as a processing hole, first use the slurry outlet hole as a filling hole to inject a sealing material into the insertion hole, the sealing material is used to seal the cavity between the insertion hole and the second slurry outlet pipe, and then install the plugging screw to penetrate the second slurry outlet pipe, and by rotating the second slurry outlet pipe, the second slurry outlet pipe is connected to the barrel and inserted into the rock mass. In this process, the plugging screw plays a role in plugging the second slurry outlet pipe, preventing the sealing material from entering the second slurry outlet pipe, and plugging the second slurry outlet pipe after solidification. In a specific embodiment, screws of different sizes for plugging the second slurry outlet pipe are configured for the second slurry outlet pipe, and another screw size is shorter than the second slurry outlet pipe, and is used to plug the second slurry outlet pipe during the grouting process.

[0030] In a specific embodiment, the top and bottom ends of the cylinder are both provided with connecting flanges, and the top end plate and the bottom end plate are both detachably connected to the connecting flanges on the cylinder through connecting screws;

[0031] The connecting flange is integrally formed on the cylinder.

[0032] The design features of this scheme are: the screw connection method formed by the top end plate and the bottom end plate with the cylinder respectively makes the top end plate and the bottom end plate removable relative to the cylinder. After the top end plate is removed, it is convenient to set the rock mass, epoxy putty and other contents in the cylinder. The top end plate and the bottom end plate are both removable to facilitate sampling of the rock mass after grouting for subsequent property testing. The design purpose of the connecting flange integrally formed on the cylinder is to ensure the mechanical properties of each position of the cylinder, so as to ensure the pressure resistance of the cylinder in repeated use cycles. However, it should be noted that since the grouting cylinder is used as an internal pressure container, it should be stipulated in the usage specifications to carry out periodic nondestructive testing.

[0033] The present scheme also relates to an indoor simulated grouting test device for fault and fracture zone rock mass, comprising a grouting tube as described in any one of the above items, and also comprising a grouting pump for injecting grouting material into the tube, wherein the grouting pump is a double-liquid grouting pump with a grouting adjusting device, and the grouting adjusting device is used to adjust the ratio of the two grouting materials pumped by the grouting pump.

[0034] Regarding the above test device, it should be particularly pointed out that: the dual-liquid grouting pump can realize the simultaneous grouting of different phases of grouting materials, and the different phases are mixed in the pipeline, so as to avoid the grouting materials from volatilizing in the environment due to the need for external mixing, thereby affecting the working environment; the slurry mixing device is used to adapt to different grouting material ratios to meet the needs of the current test and different tests.

[0035] The present solution also relates to an indoor simulated grouting test method for fault and fracture zone rock mass, which is implemented based on the grouting tube as described in any one of the above items;

[0036] The method comprises the following steps:

[0037] The rock mass to be grouted is placed in the cylinder and supported on the bottom end plate, and a particle cushion layer is arranged between the grouting surface of the rock mass and the grouting pipe outlet on the bottom end plate;

[0038] On the outside of the cylinder, the slurry outlet hole on the cylinder is used as a processing hole to process an insertion hole for a second slurry outlet pipe on the rock sample;

[0039] On the outside of the cylinder, a slurry outlet hole on the cylinder is used as a filling hole to inject a sealing material into the insertion hole, wherein the sealing material is used to seal the cavity between the insertion hole and the second slurry outlet pipe;

[0040] A second pulp outlet pipe is installed on the pulp outlet hole, and the front end of the second pulp outlet pipe is inserted into the insertion hole;

[0041] The cavity between the rock sample and the cylinder is filled with epoxy cement, and after the epoxy cement is cured, a pressure ring is placed in the cylinder and supported on the epoxy cement, wherein the contact surface between the pressure ring and the epoxy cement is located at the edge of the epoxy cement and extends along the circumferential direction of the cylinder;

[0042] Using a clamping device to provide pressure to the pressure ring toward the bottom end of the cylinder to maintain the position of the pressure ring in the height direction of the cylinder;

[0043] The cavity at the upper end of the cylinder is filled with granular fillers, and then a top end plate is installed at the upper end of the cylinder;

[0044] A grouting pump is used, and the grouting material is grouted into the rock mass encapsulated in the cylinder by utilizing the grouting pipe, and the grouting parameters during the grouting process are recorded.

[0045] The above method is a method of using the grouting tube to carry out an indoor grouting simulation test on rock samples collected on site.

[0046] The present invention has at least one of the following beneficial effects:

[0047] The lining layer provided by this scheme is beneficial to the grouting test in terms of test convenience, simple operation, and tightness of fit between the epoxy putty and the cylinder.

[0048] The inner lining layer and compression ring provided in this solution can effectively reduce the requirements for the bonding strength between the epoxy putty and the bonding surface, reduce the requirements for the flexibility of the epoxy putty, and avoid the expansion of existing cracks during the grouting process. From the perspectives of epoxy putty material selection, proportioning, and maintenance, the purpose of reducing the requirements for the epoxy putty used in the test is achieved.

[0049] The clamping device provided in this solution can ensure the reliability of the compression ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a cross-sectional view of a specific embodiment of a grouting tube for indoor simulated grouting test of fault and fracture zone rock mass described in this scheme;

[0051] Figure 2 for Figure 1 A magnified view of part A;

[0052] Figure 3 for Figure 1 Magnified view of part B.

[0053] The reference numerals in the figure are: 1. top end plate, 2. internal threaded hole, 3. internal hexagonal screw, 4. pressure ring, 5. cylinder, 6. first slurry outlet pipe, 7. inner lining layer, 8. second slurry outlet pipe, 9. bottom end plate, 10. slurry inlet pipe, 11. outer lining plate, 12. locking cap, 13. plugging screw, 14. slurry outlet hole. DETAILED DESCRIPTION

[0054] The present invention is further described in detail below in conjunction with embodiments, but the present invention is not limited to the following embodiments:

[0055] Embodiment 1:

[0056] like Figures 1 to 3 As shown, the grouting cylinder for indoor simulated grouting test of fault and fracture zone rock mass comprises a cylinder 5, the top end plate 1 for closing the top end is arranged at the top of the cylinder 5, the bottom end plate 9 for closing the bottom end is arranged at the bottom end of the cylinder 5, and the inner wall of the cylinder 5 is adhered with an inner lining layer 7 by hot melt adhesive;

[0057] It also includes a plate ring-shaped pressure ring 4, the shape of which is adapted to the inner hole at the upper end of the cylinder 5: after the rock mass to be grouted is installed in the cylinder 5 and the gap between the rock mass and the cylinder 5 is sealed with epoxy glue, the pressure ring 4 can be placed into the cylinder 5 from the top end of the cylinder 5 and supported on the epoxy glue, and the contact surface between the pressure ring 4 and the epoxy glue is located at the edge of the epoxy glue and extends along the circumferential direction of the cylinder 5;

[0058] It also includes a clamping device connected to the inner wall of the cylinder 5 , and the clamping device is used to provide pressure for the pressure ring 4 toward the bottom end of the cylinder 5 .

[0059] When using the grouting tube to perform indoor simulated grouting of the rock mass, the rock mass installation, epoxy mortar packaging between the rock mass and the cylinder 5, grouting tube packaging, and step-by-step increase of grouting pressure are completed in the corresponding order until the grouting under the highest pressure is completed (the relevant pressure is determined according to the rock sample and needs, for example, the single-stage pressure increase gradient adopts 0.2Mpa and the maximum pressure is 3Mpa). The epoxy mortar is used to limit the flow path of the grouting material, specifically to block the rock sample so that the grouting material enters the bottom of the cylinder 5 from the slurry inlet pipe 10 on the bottom end plate 9, passes through the granular cushion layer on the bottom side of the cylinder 5 from bottom to top, enters the rock sample from the bottom of the rock sample, flows and diffuses in the rock sample, slurries out from the top of the rock sample and then passes through the granular cushion layer on the top side of the cylinder 5, and then flows out from the first slurry outlet pipe 6, and flows out from the second slurry outlet pipe 8 on the side of the cylinder 5. The end of the second slurry outlet pipe 8 is inserted into the insertion hole of the rock mass, and the outer periphery of the second slurry outlet pipe 8 and the wall of the insertion hole are sealed with a sealing material. In the specific grouting, due to the pressure difference between the upper and lower ends of the rock mass, the bonding structure formed by the rock mass and the epoxy putty is supported by the top particle cushion under the grouting pressure, but the particle cushion cannot ensure complete compaction. Therefore, the bonding structure has the possibility of upward movement under the pressure difference, which becomes an inducing factor affecting the reliability of the epoxy putty sealing the cavity between the rock mass and the cylinder 5, such as cracking of the epoxy putty and separation of the epoxy putty from the cylinder 5. The specific reasons include: internal stress in the epoxy putty after curing, inappropriate proportion of the epoxy putty, inappropriate curing and curing process of the epoxy putty, inappropriate cleanliness and / or roughness of the inner wall of the cylinder 5, etc. In order to reduce this possibility, the present scheme provides the above technical scheme.

[0060] Specifically, before the rock mass is loaded into the cylinder 5, the inner lining layer 7 is pasted on the inner wall of the cylinder 5 by means of hot melt adhesive. The inner surface of the inner lining layer 7 is cleaned, dried, roughened, etc. to improve the surface quality of the surface for epoxy glue to bond, and to reduce the possibility of the epoxy glue being separated from the inner lining layer 7 during the grouting process and the formation of a leakage flow channel for the grouting material between the inner lining layer 7 and the epoxy glue. After the test is completed, the rock sample is cored, and the attachments in the cylinder 5 are cleaned, the inner lining layer 7 can be torn off the cylinder 5 by heating the hot melt adhesive, so that a new inner lining layer 7 can be replaced in the next test. In this way, the inner wall of the cylinder 5 is not damaged. Since it is the contact surface that is in direct contact with the epoxy putty, the cylinder 5 will not be damaged during the roughness treatment. Therefore, this solution is beneficial to the long-term reliable pressure resistance of the cylinder 5. At the same time, compared with the inner wall of the cylinder 5 as the contact surface that is in direct contact with the epoxy putty, from the residual angle of cleaning the inner wall of the cylinder 5 in the last test, this solution can complete the cleaning after tearing off the inner lining layer 7. Therefore, this solution also has the characteristic of improving the convenience of the test. At the same time, compared with the steel cylinder 5, the inner lining layer 7 can be made of plastic. When the inner wall of the inner lining layer 7 is roughened to obtain a rough surface, the surface can be roughened by a simple grinding operation, which has the characteristic of simple operation. In summary, the inner lining layer 7 provided by this solution is beneficial to the grouting test from the perspectives of test convenience, simplicity of operation, and tightness of the epoxy putty and the cylinder 5.

[0061] On the other hand, the present solution is to configure the cylinder 5 with a pressure ring 4 and a clamping device. The specific method of use is as follows: after the epoxy putty is poured and solidified, the pressure ring 4 provides support for the top of the bonding structure with the assistance of the clamping device, and the pressure ring 4 is inserted into the cylinder 5 from the top end of the cylinder 5 and supported on the epoxy putty. The contact surface between the pressure ring 4 and the epoxy putty is located at the edge of the epoxy putty and extends along the circumferential direction of the cylinder 5. In this way, for the possible upward movement of the bonding structure under pressure, resulting in cracking and detachment of the bonding surface, the pressure ring 4 reduces the displacement of the bonding structure by providing support for the bonding structure. This measure can effectively reduce the requirements for the bonding strength between the epoxy putty and the bonding surface, reduce the requirements for the flexibility of the epoxy putty, avoid the expansion of the cracks that have been formed during the grouting process, etc. From the perspectives of epoxy putty material selection, proportioning, and maintenance, the purpose of reducing the requirements for the epoxy putty used in the test is achieved.

[0062] On the other hand, by arranging the clamping device on the cylinder 5, compared with connecting the clamping device to the top end plate 1, the process of the top end plate 1 sealing the top of the cylinder 5 can be avoided. Because the top end plate 1 keeps moving downward, the position of the pressure ring 4 is kept pressed downward by the clamping device, causing the epoxy resin structure to be destroyed under the pressure or the connection surface with the outer peripheral lining layer 7 to be destroyed, thereby ensuring the reliability of the use of the pressure ring 4.

[0063] More specifically, in order to ensure the pressure resistance of the cylinder 5 during the grouting process, so that the pressure ring 4 can act on the edge of the epoxy putty, and ensure the adhesion quality of the bonding surface between the epoxy putty and the lining layer 7, the cylinder 5 is a cylinder, the pressure ring 4 is a ring, and the outer diameter of the pressure ring 4 is equal to the inner diameter of the cylinder 5.

[0064] More specifically, in order to make the pressure ring 4 have a larger contact area with the combination structure so as to exert the epoxy cement crack protection function, the inner diameter of the pressure ring 4 is set to be consistent with the outer diameter of the rock coring barrel, and the difference between the inner diameter of the pressure ring 4 and the outer diameter of the rock coring barrel is less than 3mm.

[0065] More specifically, as a technical solution with low cost for using the inner lining layer 7 and easy roughening of the inner wall of the inner lining layer 7, the inner lining layer 7 is a plastic plate layer with a smooth outer surface and a rough inner surface formed by roughening, and the outer surface is bonded to the inner wall of the cylinder 5 by hot melt adhesive. In this solution, since it is inconvenient to complete the exhaust and glue injection after the initial bonding between the outer surface of the inner lining layer 7 and the cylinder 5, in order to facilitate the bonding quality of the hot melt adhesive, the outer surface is set to a smooth surface, for example, after applying the hot melt adhesive, subsequent pressing is performed to form a bonding connection relationship. For the inner surface, it is used as a bonding surface with epoxy glue during use. After roughening, the bonding relationship formed by the rough surface can improve the bonding strength between the inner lining layer 7 and the epoxy glue by injecting epoxy glue in the corresponding cavity.

[0066] More specifically, the inner lining layer 7 is an integrally formed cylindrical structure or a cylindrical structure formed by overlapping or bonding the ends;

[0067] When the inner lining layer 7 is an integrally formed cylindrical structure, the outer diameter of the inner lining layer 7 is equal to the inner diameter of the cylinder 5. When the inner lining layer 7 is a cylindrical structure formed by overlapping or bonding the ends, hot melt adhesive is provided between each position of the outer surface of the inner lining layer 7 and the cylinder 5.

[0068] For the cylinder section with the inner lining layer 7 provided on the cylinder body 5, the inner lining layer 7 covers the entire surface of the cylinder section except the slurry outlet hole 14. Two structural forms of the inner lining layer 7 are provided above. When it is an integrally formed structure, that is, the inner lining layer 7 itself is a cylindrical structure with an outer diameter consistent with the inner diameter of the cylinder body 5, and it is required to customize the inner lining layer 7 of a specific size for the cylinder body 5 of a specific size. When it is a cylindrical structure formed by overlapping or bonding the ends, the inner lining layer 7 can be made of a coil. When it is used specifically, the plate used as the inner lining layer 7 is cut out according to the target cylinder body 5, and then rolled and pasted into the inside of the cylinder body 5. The coating of the hot melt adhesive and the covering of the inner lining layer 7 are used to ensure the reliability of the connection between the inner lining layer 7 and the cylinder body 5, and avoid the formation of a leakage channel for the grouting material between the cylinder body 5 and the inner lining layer 7.

[0069] More specifically, the clamping device includes a plurality of clamping components, the clamping components including an internal threaded hole 2 provided on the inner wall of the upper end of the barrel 5 and an internal hexagonal screw 3 threadedly connected to the internal threaded hole 2, the internal threaded hole 2 starting from the top of the barrel 5 and extending along the height direction of the barrel 5, the internal threaded hole 2 intersecting with the inner wall of the barrel 5, and the lower end of the internal hexagonal screw 3 exposed in the barrel 5;

[0070] The pressing components are arranged at intervals in the circumferential direction of the cylinder 5 .

[0071] The above provides a specific implementation method of the clamping device, that is, an internal helical screw and an internal threaded hole 2 form a clamping assembly that provides support for the top of the pressure ring 4. For example, even if the on-site sampling size of the rock sample is consistent, since cement mortar needs to be set on the outside of the rock sample for reinforcement and protection, it involves transportation and sample preparation before the test in the later stage, so the size of the rock sample used for the test is uncontrollable. In the above scheme, according to the position of the top of the rock sample in the barrel 5, after it is placed in the barrel 5 below the pressure ring 4 and supported on the combining structure, the internal hexagonal screw 3 is rotated to move the internal hexagonal screw 3 in the internal threaded hole 2 to a position where the lower end can support the pressure ring 4. Multiple clamping assemblies are used to provide multi-point support for the pressure ring 4 arranged at intervals along the circumferential direction. The intersection of the internal threaded hole 2 and the inner wall of the barrel 5 is: the internal threaded hole 2 is not a complete internal threaded hole 2. In this way, the internal hexagonal screw 3 on the internal threaded hole 2 can be partially exposed outside the internal threaded hole 2, so that the lower end of the internal hexagonal screw 3 can be used to provide support for the pressure ring 4. By adopting this solution, before the hexagonal screw 3 is installed in the internal threaded hole 2, the clamping assembly does not affect the internal space of the cylinder 5, which facilitates the implementation of rock placement and epoxy cement pouring. At the same time, the position of the hexagonal screw 3 can be linearly adjusted according to the position of the top surface of the epoxy cement, and has good adaptability to rocks of different heights.

[0072] More specifically, it also includes a thread protection layer, which is coated on the threads of the internal thread hole 2 and the internal hexagonal screw 3, and the thread protection layer is a thread fastening glue or a thread sealing glue.

[0073] The purpose of setting up the above scheme is: after the grouting material is poured, it is generally necessary to obtain the grouting parameters through the bottom, top and side of the grouting tube, so the grouting material will fill the internal space of the grouting tube. With this scheme, the thread protective layer is coated after the hexagonal screw 3 moves down into place. When cleaning the residue in the grouting tube later, the gap on the thread can be restored by tearing off the thread protective layer, eliminating the tedious work of removing the residue in the thread and improving the convenience of using the grouting tube.

[0074] More specifically, in order to make the thread protective layer easy to tear and separate from the thread in a large-piece manner, the thread protective layer adopts a low-strength thread fastening glue or a thread sealant that is soft after curing.

[0075] More specifically, it also includes a second pulp outlet pipe 8 arranged on the side wall of the cylinder 5, a pulp outlet hole 14 which is a threaded hole is arranged on the side wall of the cylinder 5, and the second pulp outlet pipe 8 is connected to the pulp outlet hole 14 through an external external thread;

[0076] It also includes a locking cap 12 threadedly connected to the second pulp outlet pipe 8, and the locking cap 12 is located on the second pulp outlet pipe 8 outside the cylinder 5;

[0077] The plugging screw 13 is threadedly connected to the second slurry outlet pipe 8 , and the length of the plugging screw 13 satisfies that the plugging screw 13 can pass through the second slurry outlet pipe 8 .

[0078] In the above scheme, for the overflow of grouting material from the side of the cylinder 5, the second slurry outlet pipe 8 is used as a conduit, and the second slurry outlet pipe 8 is set to be threadedly connected to the slurry outlet hole 14, so as to facilitate the adjustment of the insertion depth of the second slurry outlet pipe 8 into the rock sample according to needs. The locking cap 12 is used to lock the second slurry outlet pipe 8 after the insertion depth of the second slurry outlet pipe 8 is adjusted. Specifically, the locking cap 12 can be rotated to lock the second slurry outlet pipe 8 by squeezing the locking cap 12 and the outer wall of the cylinder 5 or the locking cap 12 and the outer lining plate 11 on the outer wall of the cylinder 5. The plug screw 13 is used to lock the second slurry outlet pipe 8. In: After drilling an insertion hole for the rock sample inside the barrel 5 using the slurry outlet hole 14 as a processing hole, first use the slurry outlet hole 14 as a filling hole to inject a sealing material into the insertion hole, the sealing material is used to seal the cavity between the insertion hole and the second slurry outlet pipe 8, and then install the plugging screw 13 to penetrate the second slurry outlet pipe 8, and by rotating the second slurry outlet pipe 8, complete the connection between the second slurry outlet pipe 8 and the barrel 5 and insert it into the rock mass. In this process, the plugging screw 13 plays a role in plugging the second slurry outlet pipe 8, preventing the sealing material from entering the second slurry outlet pipe 8, and plugging the second slurry outlet pipe 8 after solidification. More specifically, the second slurry outlet pipe 8 is equipped with screws of different sizes for plugging the second slurry outlet pipe 8, and another screw size is shorter than the second slurry outlet pipe 8, which is used to plug the second slurry outlet pipe 8 during the grouting process.

[0079] More specifically, the top and bottom ends of the barrel 5 are both provided with connecting flanges, and the top end plate 1 and the bottom end plate 9 are both detachably connected to the connecting flanges on the barrel 5 through connecting screws;

[0080] The connecting flange is integrally formed on the cylinder 5 .

[0081] The design features of this solution are: the screw connection method formed by the top end plate 1 and the bottom end plate 9 with the cylinder 5 respectively makes the top end plate 1 and the bottom end plate 9 removable relative to the cylinder 5. After the top end plate 1 is removed, it is convenient to set the rock mass, epoxy putty and other contents in the cylinder 5. The top end plate 1 and the bottom end plate 9 are both removable to facilitate sampling of the rock mass after grouting for subsequent property testing. The design purpose of the connecting flange integrally formed on the cylinder 5 is to ensure the mechanical properties of each position of the cylinder 5, so as to ensure the compressive resistance of the cylinder 5 in repeated use cycles. However, it should be noted that since the grouting cylinder is used as an internal pressure container, it should be stipulated in the usage specifications to carry out periodic nondestructive testing.

[0082] The present embodiment also relates to an indoor simulated grouting test device for fault and fracture zone rock mass, comprising a grouting tube as described in any one of the above items, and also comprising a grouting pump for injecting grouting material into the tube body 5, wherein the grouting pump is a double-liquid grouting pump with a grouting adjusting device, and the grouting adjusting device is used to adjust the ratio of the two grouting materials pumped by the grouting pump.

[0083] Regarding the above test device, it should be particularly pointed out that: the dual-liquid grouting pump can realize the simultaneous grouting of different phases of grouting materials, and the different phases are mixed in the pipeline, so as to avoid the grouting materials from volatilizing in the environment due to the need for external mixing, thereby affecting the working environment; the slurry mixing device is used to adapt to different grouting material ratios to meet the needs of the current test and different tests.

[0084] This embodiment also relates to a fault and fracture zone rock mass indoor simulation grouting test method, the method is implemented based on the grouting tube as described in any one of the above;

[0085] The method comprises the following steps:

[0086] The rock mass to be grouted is placed in the cylinder 5 and supported on the bottom end plate 9, and a particle cushion layer is provided between the grouting surface of the rock mass and the outlet of the grouting pipe 10 on the bottom end plate 9;

[0087] On the outside of the cylinder 5, the slurry outlet hole 14 on the cylinder 5 is used as a processing hole to process an insertion hole for the second slurry outlet pipe 8 on the rock sample;

[0088] On the outside of the cylinder 5, the slurry outlet hole 14 on the cylinder 5 is used as a filling hole to inject a sealing material into the insertion hole, and the sealing material is used to seal the cavity between the insertion hole and the second slurry outlet pipe 8;

[0089] A second pulp outlet pipe 8 is installed on the pulp outlet hole 14, and the front end of the second pulp outlet pipe 8 is inserted into the insertion hole;

[0090] The gap between the rock sample and the cylinder 5 is filled with epoxy cement, and after the epoxy cement is cured, the pressure ring 4 is placed in the cylinder 5 and supported on the epoxy cement, and the contact surface between the pressure ring 4 and the epoxy cement is located at the edge of the epoxy cement and extends along the circumferential direction of the cylinder 5;

[0091] Using a clamping device to provide pressure to the pressing ring 4 toward the bottom end of the cylinder 5 to maintain the position of the pressing ring 4 in the height direction of the cylinder 5;

[0092] The cavity at the upper end of the cylinder 5 is filled with granular filler, and then the top end plate 1 is installed at the upper end of the cylinder 5;

[0093] A grouting pump is used, and the grouting material is grouted into the rock mass encapsulated in the cylinder 5 by using the grouting pipe 10, and the grouting parameters during the grouting process are recorded.

[0094] The above method is a method of using the grouting tube to carry out an indoor grouting simulation test on rock samples collected on site.

[0095] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific embodiments of the present invention are limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, other embodiments obtained without departing from the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A grouting cylinder for indoor simulated grouting test of fault and fracture zone rock mass, comprising a cylinder (5), the top end plate (1) for sealing the top end is arranged at the top of the cylinder (5), and the bottom end plate (9) for sealing the bottom end is arranged at the bottom of the cylinder (5), characterized in that: An inner lining layer (7) is adhered to the inner wall of the cylinder (5) by hot melt adhesive; It also includes a plate-ring-shaped pressure ring (4), the outer shape of which is adapted to the inner hole at the upper end of the cylinder (5): after the rock mass to be grouted is installed in the cylinder (5) and the gap between the rock mass and the cylinder (5) is sealed with epoxy glue, the pressure ring (4) can be inserted into the cylinder (5) from the top end of the cylinder (5) and supported on the epoxy glue, and the contact surface between the pressure ring (4) and the epoxy glue is located at the edge of the epoxy glue and extends along the circumferential direction of the cylinder (5); It also comprises a pressing device connected to the inner wall of the cylinder (5), wherein the pressing device is used to provide pressure for the pressure ring (4) toward the bottom end of the cylinder (5).

2. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 1 is characterized in that: The barrel (5) is a cylinder, the pressure ring (4) is a circular ring, and the outer diameter of the pressure ring (4) is equal to the inner diameter of the barrel (5).

3. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 1, characterized in that: The inner lining layer (7) is a plastic plate layer having a smooth outer surface and a rough inner surface formed by roughening treatment, and the outer surface is bonded to the inner wall of the cylinder (5) by hot melt adhesive.

4. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 1, characterized in that: The inner lining layer (7) is an integrally formed cylindrical structure or a cylindrical structure formed by overlapping or bonding the ends; When the inner lining layer (7) is an integrally formed cylindrical structure, the outer diameter of the inner lining layer (7) is equal to the inner diameter of the cylinder (5); when the inner lining layer (7) is a cylindrical structure formed by overlapping or bonding the ends, hot melt adhesive is provided between each position of the outer surface of the inner lining layer (7) and the cylinder (5); For a cylinder section on which an inner lining layer (7) is arranged on the cylinder body (5), the inner lining layer (7) covers the entire surface of the cylinder section except for the pulp outlet hole (14).

5. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 1, characterized in that: The clamping device comprises a plurality of clamping assemblies, wherein the clamping assemblies comprise an internal threaded hole (2) arranged on the inner wall of the upper end of the barrel (5) and a hexagonal screw (3) threadedly connected in the internal threaded hole (2), wherein the internal threaded hole (2) starts from the top end of the barrel (5) and extends along the height direction of the barrel (5), the internal threaded hole (2) intersects with the inner wall of the barrel (5), and the lower end of the hexagonal screw (3) is exposed in the barrel (5); The pressing components are arranged at intervals in the circumferential direction of the cylinder (5).

6. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 5, characterized in that: It also includes a thread protection layer, which is coated on the threads of the internal thread hole (2) and the internal hexagonal screw (3), and the thread protection layer is a thread fastening glue or a thread sealing glue.

7. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to claim 1, characterized in that: It also comprises a second pulp outlet pipe (8) arranged on the side wall of the cylinder (5), a pulp outlet hole (14) which is a threaded hole is arranged on the side wall of the cylinder (5), and the second pulp outlet pipe (8) is connected to the pulp outlet hole (14) through an external external thread; It also includes a locking cap (12) threadedly connected to the second pulp outlet pipe (8), wherein the locking cap (12) is located on the second pulp outlet pipe (8) outside the cylinder (5); It also comprises a plugging screw (13) threadedly connected to the second pulp outlet pipe (8), and the length of the plugging screw (13) satisfies that the plugging screw (13) can pass through the second pulp outlet pipe (8).

8. The grouting tube for indoor simulated grouting test of fault and fracture zone rock mass according to any one of claims 1 to 7, characterized in that: The top and bottom ends of the barrel (5) are both provided with connecting flanges, and the top end plate (1) and the bottom end plate (9) are both detachably connected to the connecting flanges on the barrel (5) via connecting screws; The connecting flange is integrally formed on the cylinder (5).

9. Indoor simulation grouting test device for fault and fracture zone rock mass, characterized in that: The grouting barrel comprises the grouting barrel as claimed in any one of claims 1 to 8, and further comprises a grouting pump for injecting grouting material into the barrel (5), wherein the grouting pump is a dual-liquid grouting pump with a grouting adjusting device, and the grouting adjusting device is used to adjust the ratio of two grouting materials pumped by the grouting pump.

10. Indoor simulation grouting test method for fault and fracture zone rock mass, characterized in that: The method is implemented based on the grouting tube described in any one of claims 1 to 8; The method comprises the following steps: The rock mass to be grouted is placed in the cylinder (5) and supported on the bottom end plate (9), and a particle cushion layer is provided between the grouting surface of the rock mass and the outlet of the grouting pipe (10) on the bottom end plate (9); On the outside of the cylinder (5), a slurry outlet hole (14) on the cylinder (5) is used as a processing hole to process an insertion hole for a second slurry outlet pipe (8) on the rock sample; On the outside of the cylinder (5), a slurry outlet hole (14) on the cylinder (5) is used as a filling hole to inject a sealing material into the insertion hole, wherein the sealing material is used to seal the cavity between the insertion hole and the second slurry outlet pipe (8); A second pulp outlet pipe (8) is installed on the pulp outlet hole (14), and the front end of the second pulp outlet pipe (8) is inserted into the insertion hole; The cavity between the rock sample and the cylinder (5) is filled with epoxy cement, and after the epoxy cement is solidified, a pressure ring is placed in the cylinder (5) and supported on the epoxy cement, wherein the contact surface between the pressure ring (4) and the epoxy cement is located at the edge of the epoxy cement and extends along the circumferential direction of the cylinder (5); Using a clamping device to provide pressure to the pressure ring (4) toward the bottom end of the cylinder (5) so as to maintain the position of the pressure ring (4) in the height direction of the cylinder (5); The cavity at the upper end of the cylinder (5) is filled with granular filler, and then a top end plate (1) is installed at the upper end of the cylinder (5); A grouting pump is used and the grouting pipe (10) is used to grout the rock mass encapsulated in the cylinder (5) with grouting material, and grouting parameters during the grouting process are recorded.

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