Testing device for water injection test

Abstract

The invention relates to the technical field of geotechnical engineering geological investigation, in particular to a testing device for a water injection test, which comprises a wall protecting pipe, a wall protecting floral pipe, a first annular air bag and a testing assembly, one end of the wall protecting pipe is provided with a limiting protruding ring protruding out of the inner pipe wall of the wall protecting pipe. An abutting ring which protrudes out of the outer pipe wall of the wall protecting floral pipe and is used for being matched with the limiting protruding ring in an abutting mode is arranged on the outer pipe wall of the wall protecting floral pipe. A plurality of water seepage holes are formed in the pipe wall of the wall protecting floral pipe in a penetrating manner; the first annular air bag abuts against the end face of the bottom end of the wall protecting pipe in a sealed mode, can expand and deform in the radial direction after being pressed in the axial direction, and can recover to the initial shape after pressure is released. The outer diameter of the first annular airbag after compression deformation is greater than the diameter of the base hole; the testing assembly is used for injecting water into the wall protection floral tube so as to test the permeability coefficient of the rock-soil layer of the test section. The method has the effects that the complexity and the test cost of water injection test operation are reduced, and the test efficiency and accuracy are improved.

Description

Technical Field

[0001] The present application relates to the technical field of geotechnical engineering geological survey, and in particular to a testing device for water injection test. Background Art

[0002] During the construction of water conservancy and hydropower dams, transportation tunnels and other projects, it is usually necessary to measure and evaluate the degree of crack development and permeability of the rock and soil layer serving as the dam body or the rock and soil layer serving as the tunnel body to ensure that the rock and soil layer under construction meets the requirements. The permeability coefficient is one of the important parameters for evaluating the degree of crack development and permeability. The water injection test is an in-situ test method that determines the permeability coefficient of the rock and soil layer by drilling a hole into the rock and soil layer and injecting water into the hole. The water injection test is generally divided into a borehole constant head water injection test and a borehole reduced head water injection test. The borehole constant head water injection test measures the rate of change of the water injection volume of the rock and soil layer over time while keeping the head (water level) height fixed. The borehole reduced head water injection test measures the rate of change of the head (water level) height over time to determine the permeability coefficient of the rock and soil layer.

[0003] In engineering applications, the typical process for a water injection test is as follows: A drill is first used to drill a foundation hole. During the drilling process, the non-test rock and soil layers are first penetrated. A retaining wall pipe is then installed in this non-test rock and soil layer to protect the hole wall and isolate the non-test rock and soil layers. Once the retaining wall pipe is installed, drilling continues until the test rock and soil layers are penetrated. A retaining wall pipe is then installed in the test rock and soil layers. Finally, the water injection test can begin to test the permeability of the test rock and soil layers. This method creates a gap between the retaining wall pipe and the foundation hole wall, making it easy for water from the non-test rock and soil layers to seep into the retaining wall pipe, affecting the accuracy of the permeability test results for the test rock and soil layers. To address this issue, existing techniques typically employ an inflatable and deflable airbag installed between the retaining wall pipe and the foundation hole wall. Once the retaining wall pipe is installed, the airbag is inflated, causing the inflated airbag to block the gap between the retaining wall pipe and the foundation hole wall.

[0004] Regarding the aforementioned related technologies, the testing process is cumbersome, complex, and requires high equipment costs, resulting in low test efficiency. On the one hand, the airbag inflation and deflation process is tedious and requires a specialized high-pressure air pump, which increases equipment costs. On the other hand, the base hole depth can range from a dozen meters to hundreds of meters. Since the wall-protecting flower tubes are independently installed deep within the base hole, special pipe extraction equipment is required. Often, due to cost considerations, the wall-protecting flower tubes are simply discarded, resulting in a waste of resources. Summary of the Invention

[0005] In order to reduce the complexity and test cost of water injection test operations and improve test efficiency and accuracy, the present application provides a test device for water injection test.

[0006] The present application provides a testing device for water injection test using the following technical solution: This method has complicated steps, complex operation, high equipment cost and low test efficiency. A testing device for a water injection test, comprising: A wall protection tube is arranged in the non-test section of the base hole, and one end of the wall protection tube is provided with a limiting convex ring protruding from the inner tube wall thereof; The wall-protecting flower tube is arranged in the test section of the base hole. The outer tube wall of the wall-protecting flower tube is provided with an abutment ring protruding from the outer tube wall and used to abut and cooperate with the limiting convex ring; a plurality of water seepage holes are opened through the tube wall of the wall-protecting flower tube; The first annular airbag is sealed against the bottom end surface of the wall protection tube. The first annular airbag can expand and deform radially after being compressed in the axial direction, and can restore its original shape after the pressure is released. The outer diameter of the first annular airbag in the initial state is smaller than the aperture of the non-test section of the base hole. The outer diameter of the first annular airbag after being compressed and deformed is larger than the aperture of the non-test section of the base hole. The test component is used to inject water into the wall protection flower tube to test the permeability coefficient of the rock and soil layer in the test section.

[0007] By adopting the above technical solution, the complexity and cost of water injection testing can be reduced, while improving test efficiency and accuracy. Specifically, during the test, water is injected into the protective wall tube through the test assembly to measure the permeability of the test section's rock and soil layer. The protective wall tube prevents the non-test section's rock and soil layer from collapsing. While preventing the test section's rock and soil layer from collapsing, the protective wall tube allows water injected into the tube to directly contact the test section's rock and soil layer through the seepage holes. Furthermore, since the protective wall tube is installed in the hole after the non-test section is drilled, the drilling of the test section's rock and soil layer must be performed within the protective wall tube. Consequently, an annular boss is formed within the base hole between the non-test and test sections. The end of the first annular airbag facing away from the protective wall tube abuts the boss. The weight of the protective wall tube compresses the first annular airbag axially, causing it to expand and deform radially, sealing against the base hole wall. This effectively blocks the gap between the protective wall tube and the base hole wall, preventing water from the non-test section's rock and soil layer from seeping into the protective wall tube, and improving the accuracy of the permeability test results for the test section's rock and soil layer. When removing the retaining wall tube, the tube is pulled up using a tube puller. The first annular airbag returns to its original shape after the pressure is relieved, reducing friction between the tube and the base hole wall during removal. This test device eliminates the need for an additional inflation device or the complex inflation and deflation of the first annular airbag, reducing the complexity and cost of the water injection test. Furthermore, the design of the retaining ring and abutment ring allows the retaining wall tube to be pulled up with it, significantly improving the convenience and efficiency of removing the retaining wall tube.

[0008] Optionally, the test assembly includes a water pump, a water injection pipe, a flow meter, a water level monitor and a control host; the water pump is used to extract water from an external source and input it into the wall-protecting flower tube through the water injection pipe; the flow meter is arranged on the water injection pipe to monitor the water flow of the water injection pipe; the water level monitor is arranged in the wall-protecting flower tube to monitor the water level in the wall-protecting flower tube; the control host is electrically connected to the flow meter and the water level monitor to analyze and calculate the permeability coefficient of the rock and soil layer in the test section By adopting the above technical solution, during the test, first, water is drawn from the external source by a water pump and input into the wall protection flower tube through the water injection pipe to provide water source for the water injection test; then the water flow in the water injection pipe is monitored by a flow meter, and the water level in the wall protection flower tube is monitored by a water level monitor, and the data of the two are analyzed and calculated by the control host, so as to accurately test the permeability coefficient of the rock and soil layer in the test section.

[0009] Optionally, the inner diameter of the first annular airbag after being compressed and deformed is smaller than the outer diameter of the wall-protecting flower tube.

[0010] By adopting the above technical solution, as the wall-protecting flower tube is lowered from the wall-protecting tube, the wall-protecting flower tube can further compress the first annular airbag, causing it to fully expand radially, thereby better sealing the gap between the wall-protecting tube and the foundation hole. This effectively prevents water from the rock and soil strata in the non-test section from seeping into the wall-protecting flower tube through the gap, thereby improving the accuracy of the permeability coefficient test results of the rock and soil strata in the test section. At the same time, the first annular airbag can seal the connecting gap between the wall-protecting tube and the wall-protecting flower tube. When the test water pressure in the wall-protecting flower tube needs to be increased, water can be injected into the wall-protecting tube to increase the test water depth, thereby increasing the water pressure in the wall-protecting flower tube. This eliminates the need for an additional pressurizer and reduces equipment costs.

[0011] Optionally, a connecting component is also included; the wall-protecting flower tube includes a plurality of segmented tubes, and the plurality of segmented tubes are sealed and connected end to end through the connecting component.

[0012] By adopting the above technical solution, the segmented pipes can be connected or removed one by one when installing or disassembling the wall-protecting flower pipe. Compared with the integral wall-protecting flower pipe, it is easier to transport and install into the test section of the base hole, thereby improving the convenience and efficiency of disassembly and assembly of the test device.

[0013] Optionally, the connecting assembly includes a clamping ring, at least two clamping blocks and a second annular airbag; the clamping ring is arranged on the inner tube wall of the segment tube and protrudes from the inner tube wall of the segment tube; the two clamping blocks are respectively arranged on both sides of one end of the segment tube, for clamping and cooperating with the clamping ring on the other segment tube, so as to realize the end-to-end connection between multiple segment tubes; the second annular airbag is arranged between the two segment tubes, for sealing the connecting gap between the two segment tubes.

[0014] By adopting the above technical solution, the clamping block and the clamping ring are clamped together to realize the end-to-end connection between multiple segmented tubes, which is convenient for the assembly and disassembly of the wall-protecting flower tubes; the second annular airbag is arranged between the two segmented tubes, which can seal the connecting gap between the two segmented tubes to prevent water leakage from the gap and ensure the accuracy of the water injection test.

[0015] Optionally, the clamping block includes an elastic part, a guide part and a clamping part; the elastic part can produce elastic deformation, one end of the elastic part is connected to the inner tube wall of the segment tube, and the other end extends out of the end part of the segment tube; the guide part is arranged at one end of the elastic part away from the segment tube, the guide part is wedge-shaped, and the narrow end of the wedge is away from the segment tube, and the wide end is close to the segment tube; the outer side spacing of the narrow ends of the two guide parts of the two clamping blocks is smaller than the inner diameter of the clamping ring, and the outer side spacing of the wide ends of the two guide parts of the two clamping blocks is greater than the inner diameter of the clamping ring; the clamping part is arranged on one side of the wedge-shaped wide surface of the guide part; when the two segment tubes are connected, the two end surfaces of the second annular airbag respectively seal and abut the two end surfaces of the two segment tubes close to each other; the two clamping blocks on the first segment tube are inserted into the clamping ring of the second segment tube, and the side of the clamping part of the first segment tube close to the first segment tube abuts against the side of the clamping ring of the second segment tube away from the first segment tube.

[0016] By adopting the above technical solution, a plurality of segmented pipes can be conveniently and stably connected to each other. Specifically, when connecting two segmented pipes, the end of one segmented pipe with the protruding clamping block is inserted into the end of the other segmented pipe without the protruding clamping block. During the process, the wedge surfaces of the two guide parts of the two clamping blocks first contact the clamping ring, initially guiding the two clamping blocks to align with the clamping ring as a whole; as the two segmented tubes continue to approach each other, the two elastic parts of the two clamping blocks are elastically deformed under the abutment of the guide parts and the clamping ring and then approach each other, making it easier for the two clamping blocks to be inserted into the clamping ring; when the two clamping blocks are moved to the predetermined position as a whole, the two guide parts of the two clamping blocks are disengaged from the abutment with the clamping ring, and the two elastic parts of the two clamping blocks return to their initial state, and the side of the two clamping parts close to the segmented tube that supports itself abuts against the side of the clamping ring away from the segmented tube to be connected, thereby realizing a stable connection between the two segmented tubes; the two end faces of the second annular airbag seal and abut against the two end faces of the two segmented tubes that are close to each other, thereby sealing the connection gap between the two segmented tubes, ensuring that water will not leak from the connection of the segmented tubes during the water injection test, thereby improving the sealing and reliability of the test device.

[0017] Optionally, the second annular airbag can expand and deform radially after being compressed in the axial direction, and can restore its original shape after the pressure is released; the outer diameter of the second annular airbag in the initial state is smaller than the outer diameter of the segmented tube, and the outer diameter of the second annular airbag after being compressed and deformed is larger than the aperture of the base hole test section; when the two segmented tubes are vertically arranged and connected, the segmented tube located above can use its own weight to squeeze the second annular airbag to deform it.

[0018] By adopting the above technical solution, the second annular airbag is set between the two segmented tubes. When the two segmented tubes are vertically connected, the upper segmented tube uses its own weight to squeeze the second annular airbag axially, causing it to expand and deform radially until the side wall of the second annular airbag is sealed and abutted against the hole wall of the base hole test section. In this way, the gap between the wall-protecting flower tube and the base hole wall can be divided into multiple sections, shortening the flow path of water flowing along the gap to flush the hole wall during water seepage, effectively reducing the scouring of the hole wall sediment by the water flow, thereby significantly reducing the risk of hole wall collapse and the sediment content in the water, reducing the interference of sediment on the test data, and helping to improve the accuracy of the test results of the permeability coefficient of the rock and soil layer in the test section. At the same time, due to the elastic properties of the second annular airbag, a certain amount of axial elastic activity margin can be provided between the segmented tubes, and a certain amount of radial activity margin can also be provided between the segmented tubes and the base hole wall. In practice, this margin of movement acts as a buffer when encountering slight vibrations or other factors that cause positional shifts, reducing potential damage from rigid connections and improving the stability of the connections between the segments and between the segments and the base hole. Furthermore, when removing a segment, the second annular airbag automatically contracts to its initial state after the segment is pulled out, preventing friction with the base hole wall and hindering removal.

[0019] Optionally, a segmented component is also included, which includes a first segmented airbag, a second segmented airbag, an air pump and a connecting tube. The first segmented airbag and the second segmented airbag are movably arranged in multiple segmented tubes connected end to end; the air pump is used to inflate the first segmented airbag and the second segmented airbag so that the first segmented airbag and the second segmented airbag block the segmented tubes at different positions after expansion, and form independent test cavities in the multiple segmented tubes; the connecting tube is connected to the test cavity, and water can be injected into the test cavity through the connecting tube.

[0020] By adopting the above technical solution, the setting of the segmented component enables the first segmented airbag and the second segmented airbag to be moved to different positions in multiple segmented tubes connected end to end. After being inflated by an air pump, the segmented tubes are blocked, thereby forming an independent test cavity in the multiple segmented tubes. Water is injected into the test cavity through a connecting pipe, and the permeability coefficient of the rock and soil layers in the test sections at different positions can be tested separately, thereby improving the flexibility and pertinence of the test.

[0021] Optionally, a first skirt and a second skirt are provided on the outer side wall of the second annular airbag; the first ends of the first skirt and the second skirt are connected to the outer side wall of the second annular airbag; the second ends of the first skirt and the second skirt extend toward the segmented tube close to the two ends of the second annular airbag respectively; in the initial state of the second annular airbag, the first skirt and the second skirt are both located in the circumferential surface where the outer tube wall of the segmented tube is located; after the second annular airbag is subjected to axial pressure, the second ends of the first skirt and the second skirt can approach each other and abut against the wall of the base hole.

[0022] By adopting this technical solution, the ends of the first and second skirts, distal from the segmented tubes, can move closer together and abut against the base hole wall when the second annular airbag is subjected to axial pressure. This enhances the sealing of the gap connecting the two segmented tubes, reduces the infiltration of water from the rock layer into the test section through the gap, and improves the accuracy of the permeability coefficient test results. Furthermore, the higher the test water pressure, the tighter the contact between the first and second skirts and the base hole wall, resulting in better sealing performance.

[0023] Optionally, the clamping ring is detachably connected to the inner tube wall of the segment tube via a screw threadedly connected to the segment tube.

[0024] By adopting the above technical solution, when pulling up and removing the segment pipes, the segment pipes can be quickly separated by removing the clamping ring, which reduces the separation difficulty and improves the disassembly efficiency.

[0025] In summary, this application has the following beneficial technical effects: 1. It can reduce the complexity and testing costs of water injection tests, improving test efficiency and accuracy. Specifically, during testing, water can be injected into the protective wall tube through the test assembly to test the permeability of the test section's rock and soil layer. The protective wall tube prevents the non-test section's rock and soil layer from collapsing. The protective wall tube prevents the test section's rock and soil layer from collapsing and allows water injected into the tube to directly contact the test section's rock and soil layer through the seepage holes. Because the protective wall tube is installed in the hole after the non-test section is drilled, the drilling of the test section's rock and soil layer must be performed within the protective wall tube. Therefore, an annular boss is formed within the base hole between the non-test section and the test section. The end of the first annular airbag facing away from the protective wall tube abuts against the annular boss. The protective wall tube's own weight compresses the first annular airbag axially, causing the first annular airbag to expand and deform radially and then seal against the base hole wall, effectively blocking the gap between the protective wall tube and the base hole wall, preventing water from the non-test section's rock and soil layer from seeping into the protective wall tube, and improving the accuracy of the permeability test results for the test section's rock and soil layer. When removing the wall protection tube, the tube is pulled up with a tube pulling machine. The first annular airbag returns to its original shape after the pressure is released, which can reduce the friction between the wall protection tube and the base hole wall when pulling it up. This test device does not require the installation of an additional inflation device, nor does it require the complex inflation and deflation operations of the first annular airbag, which reduces the complexity and test cost of the water injection test operation. At the same time, due to the design of the limiting convex ring and the abutment ring, when pulling up the wall protection tube, the wall protection flower tube can be pulled up together, greatly improving the convenience and efficiency of removing the wall protection flower tube; 2. The second annular airbag is set between the two segmented tubes. When the two segmented tubes are connected vertically, the upper segmented tube uses its own weight to squeeze the second annular airbag axially, causing it to expand and deform radially until the side wall of the second annular airbag is sealed and abutted against the hole wall of the base hole test section. In this way, the gap between the wall-protecting flower tube and the base hole wall can be divided into multiple sections, shortening the flow path of water flowing along the gap to flush the hole wall during water seepage, effectively reducing the scouring of the hole wall sediment by the water flow, thereby significantly reducing the risk of hole wall collapse. At the same time, the sediment content caused by the entry of hole wall sediment into the water during the test is reduced, avoiding the interference of sediment on the test data, and helping to improve the accuracy of the test results of the permeability coefficient of the rock and soil layer in the test section. Moreover, due to the elastic properties of the second annular airbag, there can be a certain axial elastic activity margin between the segmented tubes, and a certain radial activity margin between the segmented tubes and the base hole wall. In actual applications, when encountering position changes caused by slight external vibrations or other factors, these movable margins can act as a buffer, reducing damage that may be caused by rigid connections and improving the stability of the connections between segment pipes and between segment pipes and base holes. In addition, when removing the segment pipe, after pulling out the segment pipe, the second annular airbag can automatically shrink to its original state, avoiding friction with the base hole wall and preventing obstacles to the removal of the segment pipe; 3. The setting of the segmented assembly enables the first segmented airbag and the second segmented airbag to be moved to different positions in multiple segmented tubes connected end to end. The airbags are inflated by an air pump to block the segmented tubes after expansion, thereby forming independent test chambers in the multiple segmented tubes. Water is injected into the test chamber through a connecting pipe, and the permeability coefficient of the rock and soil layers in the test sections at different positions can be tested separately, thereby improving the flexibility and pertinence of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application.

[0027] Figure 2 yes Figure 1 A partial enlarged view of part A.

[0028] Figure 3 Mainly display the wall protection flower tube and connection components of the embodiment of this application.

[0029] Figure 4 yes Figure 1 A partial enlarged view of part B.

[0030] Explanation of the reference numerals: 100, base hole; 101, non-test section; 102, test section; 1, wall protection tube; 11, limiting convex ring; 2, wall protection flower tube; 21, segment tube; 211, test cavity; 22, abutment ring; 23, seepage hole; 3, first annular airbag; 4, test assembly; 41, water pump; 42, water injection pipe; 43, flow meter; 44, water level monitor; 45, control host; 5, connecting assembly; 51, snap ring; 52, snap block; 521, elastic part; 522, guide part; 523, snap part; 53, second annular airbag; 531, first skirt; 532, second skirt; 6, segment assembly; 61, first segment airbag; 62, second segment airbag; 63, inflation pump; 64, connecting pipe; 7, screw. DETAILED DESCRIPTION

[0031] The following combination Figure 1-Figure 4 This application is described in further detail.

[0032] The embodiment of the present application discloses a testing device for a water injection test.

[0033] Reference Figure 1 and Figure 2In this embodiment, the test device includes a wall protection tube 1, a wall protection flower tube 2, a first annular airbag 3, a test assembly 4, a connection assembly 5, and a segment assembly 6. Specifically, the wall protection tube 1 is arranged in the non-test section 101 of the base hole 100; the wall protection tube 1 can be made of a stainless steel tube or a plastic tube, and the tube diameter is slightly smaller than the aperture of the non-test section 101 of the base hole 100, so that it can be smoothly placed in the base hole 100 during installation. A limiting convex ring 11 is installed on the inner tube wall of the bottom end of the wall protection tube 1, which protrudes from the inner tube wall of the wall protection tube 1. The limiting convex ring 11 is a circle of raised structures on the inner tube wall of the wall protection tube 1. In other embodiments, the wall protection tube 1 can also adopt a segmented structure to facilitate the installation and removal of the wall protection tube 1.

[0034] Reference Figure 1 and Figure 3 In this embodiment, the wall-protecting flower tube 2 is set in the test section 102 of the base hole 100. The wall-protecting flower tube 1 can also be made of stainless steel or plastic tube, and the diameter of the tube is slightly smaller than the diameter of the test section 102 of the base hole 100 and the inner diameter of the limiting protrusion 11. A plurality of water seepage holes 23 are opened through the middle part of the tube wall of the wall-protecting flower tube 2. The water seepage holes 23 can be of different shapes such as circular and square. Their function is to allow the water injected into the wall-protecting flower tube 2 to penetrate into the rock and soil layer of the test section 102 so as to test the permeability coefficient. The outer tube wall of the top of the wall-protecting flower tube 2 is provided with an abutment ring 22 that protrudes from its own outer tube wall and is used to abut with the limiting protrusion 11. The abutment ring 22 is a circle of raised structures on the outer tube wall of the wall-protecting flower tube 2. The diameter of the abutment ring 22 matches the inner diameter of the wall-protecting flower tube 1.

[0035] The first annular airbag 3 is a toroidal airbag made of rubber and filled with high-pressure gas. The first annular airbag 3 is sealed to the bottom end surface of the protective wall tube 1 and is coaxial with the protective wall tube 1. The outer diameter of the first annular airbag 3 in its initial state is smaller than the aperture of the non-test section 101 of the base hole 100, so that it can be placed into the base hole 100 together with the protective wall tube 1. The first annular airbag 3 is capable of radial expansion and deformation after being subjected to axial pressure, and can return to its original shape after the pressure is released. The outer diameter of the first annular airbag 3 after being compressed and deformed is larger than the aperture of the non-test section 101 of the base hole 100.

[0036] The test assembly 4 is used to inject water into the wall-protecting flower tube 2 to test the permeability coefficient of the rock and soil layer in the test section 102. The test assembly 4 includes a water pump 41, a water injection pipe 42, a flowmeter 43, a water level monitor 44, and a control unit 45. The water pump 41 draws water from an external source and delivers it to the wall-protecting flower tube 2 through the water injection pipe 42. Water pumps 41 can be of various types, such as centrifugal pumps and screw pumps, each suitable for different flow and pressure requirements. The water injection pipe 42 can be made of materials such as plastic and rubber, and its diameter can be selected based on actual needs. A flowmeter 43 is mounted on the water injection pipe 42 to monitor the water flow within the water injection pipe 42. The flowmeter 43 can be an electromagnetic flowmeter or a turbine flowmeter, for example. A water level monitor 44 is mounted inside the wall-protecting flower tube 2 to monitor the water level within the pipe. The water level monitor 44 can be a float-type water level monitor or an ultrasonic water level monitor, for example. Control host 45 is a computer equipped with programming and calculation software. It is electrically connected to flow meter 43 and water level monitor 44 to analyze and calculate the permeability coefficient of the soil layer in test section 102. Control host 45 can calculate the permeability coefficient using a corresponding algorithm based on the data provided by flow meter 43 and water level monitor 44.

[0037] In this way, after the non-test section 101 of the base hole 100 is drilled, the end of the wall protection tube 1 equipped with the first annular airbag 3 is directed downward, and the wall protection tube 1 is installed in the non-test section 101 of the base hole 100. The test section 102 of the base hole 100 is then drilled. The wall protection tube 1 can prevent the rock and soil layer in the non-test section 101 from collapsing. During this process, since the drilling of the test section 102 must be carried out within the wall protection tube 1, an annular boss is formed within the base hole 100 between the non-test section 101 and the test section 102. After the wall protection tube 1 is installed, the end of the first annular airbag 3 facing away from the wall protection tube 1 abuts against the annular boss. At this time, the weight of the wall protection tube 1 is used to axially squeeze the first annular airbag 3, causing the first annular airbag 3 to expand and deform radially and then seal against the wall of the non-test section 101 of the base hole 100, effectively blocking the gap between the wall protection tube 1 and the wall of the non-test section 101 of the base hole 100, preventing water in the rock and soil layer of the non-test section 101 from penetrating into the wall protection flower tube 2, and improving the accuracy of the permeability coefficient test results of the rock and soil layer of the test section 102. Subsequently, after the test section 102 of the base hole 100 is drilled, the end of the wall protection flower tube 2 with the abutment ring 22 is facing upward, and the wall protection flower tube 2 is installed in the test section 102 of the base hole 100 to prevent the rock and soil layer of the test section 102 from collapsing, and to allow the water injected into the wall protection flower tube 2 to directly contact the rock and soil layer of the test section 102 through the seepage hole 23. Finally, water is drawn from an external source by a water pump 41 and fed into the wall-protecting flower tube 2 through the water injection pipe 42 to provide a water source for the water injection test. A flow meter 43 monitors the water flow in the water injection pipe 42, and a water level monitor 44 monitors the water level in the wall-protecting flower tube 2. The data from both are analyzed and calculated by the control host 45, thereby accurately testing the permeability coefficient of the rock and soil layer in the test section 102. After the test is completed, the wall-protecting tube 1 is pulled out and removed using a pipe pulling machine. At this time, the first annular airbag 3 returns to its original shape after the pressure is released, reducing friction with the wall of the base hole 100. At the same time, due to the design of the limiting convex ring 11 and the abutment ring 22, when the wall-protecting tube 1 is pulled out, the wall-protecting flower tube 2 can be pulled out upward together, greatly improving the convenience and efficiency of removing the wall-protecting flower tube 2. Furthermore, this test device does not require the installation of an additional inflation device, nor does it require the complex inflation and deflation operations of the first annular airbag 3, reducing the complexity of the water injection test operation and the test cost.

[0038] It should be emphasized that, in actual construction, the width of the annular boss formed between the non-test section 101 and the test section 102 in the base hole 100 can be reserved to be larger to ensure stable support of the first annular airbag 3 .

[0039] Preferably, the inner diameter of the first annular airbag 3 after being deformed by pressure is smaller than the outer diameter of the wall-protecting flower tube 2. Thus, during the process of lowering the wall-protecting flower tube 2 into the wall-protecting flower tube 1, the wall-protecting flower tube 2 can further squeeze the first annular airbag 3, causing the first annular airbag 3 to fully expand radially, thereby better sealing the gap between the wall-protecting flower tube 1 and the base hole 100. At the same time, the first annular airbag 3 can also seal the connecting gap between the wall-protecting flower tube 1 and the wall-protecting flower tube 2. When the test water pressure in the wall-protecting flower tube 2 needs to be increased, the test water depth can be increased by injecting water into the wall-protecting flower tube 1, thereby increasing the water pressure in the wall-protecting flower tube 2. This eliminates the need for an additional pressurizer, thereby reducing equipment costs.

[0040] Reference Figure 1 and Figure 3 In this embodiment, the wall-protecting flower tube 2 includes a plurality of segmented tubes 21, and the plurality of segmented tubes 21 are sealed end to end by a connecting assembly 5, and the abutment ring 22 is located at the end of the first segmented tube 21 at the top of the plurality of segmented tubes 21 away from the other segmented tubes 21. The connecting assembly 5 includes a clamping ring 51, two clamping blocks 52 and a second annular airbag 53. The clamping ring 51 is a stainless steel ring with an outer diameter matching the inner diameter of the segmented tube 21, and has good corrosion resistance and wear resistance. The clamping ring 51 is detachably connected to the inner tube wall at the top of the segmented tube 21 by a screw 7 threaded on the segmented tube 21. The clamping block 52 is also made of stainless steel and has good corrosion resistance and wear resistance. The two clamping blocks 52 are respectively fixed on both sides of the inner tube wall at the bottom end of the segmented tube 21, and are used to clamp and cooperate with the clamping ring 51 on another segmented tube 21 to achieve the end-to-end connection between the plurality of segmented tubes 21. The second annular airbag 53 is specifically a ring-shaped airbag made of rubber and filled with high-pressure gas. The second annular airbag 53 is arranged between the two segmented tubes 21 and is coaxial with the segmented tubes 21 to seal the connecting gap between the two segmented tubes 21.

[0041] Reference Figure 3 and Figure 4The clamping block 52 includes an elastic portion 521, a guide portion 522, and a clamping portion 523. The elastic portion 521 can produce elastic deformation. The elastic portion 521 is in the shape of an elongated strip, one end of which is welded and fixed to the inner wall of the segment tube 21, and the other end extends out of the bottom end of the segment tube 21 in a direction parallel to the central axis of the segment tube 21. The guide portion 522 is arranged at the end of the elastic portion 521 that is welded and fixed away from the segment tube 21. The guide portion 522 is wedge-shaped, and the narrow end of the wedge is away from the segment tube 21, while the wide end is close to the segment tube 21. The wedge-shaped surfaces of the two guide portions 522 of the two clamping blocks 52 are facing each other. The outer distance between the narrow ends of the two guide portions 522 of the two clamping blocks 52 is smaller than the inner diameter of the clamping ring 51, and the outer distance between the wide ends of the two guide portions 522 of the two clamping blocks 52 is larger than the inner diameter of the clamping ring 51. The clamping portion 523 is a rectangular block, welded to the side of the wedge-shaped wide surface of the guide portion 522 near the bottom end of the segment tube 21. The side of the clamping portion 523 near the bottom end of the segment tube 21 is parallel to the bottom end surface of the segment tube 21, and the side of the clamping ring 51 near the bottom end of the segment tube 21 is parallel to the bottom end surface of the segment tube 21. When the two segment tubes 21 are connected, the two end surfaces of the second annular airbag 53 respectively seal against the two end surfaces of the two segment tubes 21 that are close to each other; the two clamping blocks 52 on the first segment tube 21 are inserted into the clamping ring 51 of the second segment tube 21, and the side of the clamping portion 523 of the first segment tube 21 near the first segment tube 21 abuts against the side of the clamping ring 51 of the second segment tube 21 facing away from the first segment tube 21.

[0042] In this way, the segmented tubes 21 can be connected or removed one by one, which improves the convenience of installing and removing the wall-protecting flower tubes 2 compared to the integral wall-protecting flower tubes 2. Specifically, when connecting two segmented tubes 21, the bottom end of one segmented tube 21 with the protruding clamping block 52 is inserted into the top end of the other segmented tube 21. During the process, the wedge-shaped surfaces of the two guide portions 522 of the two clamping blocks 52 first contact the clamping ring 51, and preliminarily guide the two clamping blocks 52 as a whole to align with the clamping ring 51. As the two segmented tubes 21 continue to approach, the two elastic portions 521 of the two clamping blocks 52 are elastically deformed under the contact between the guide portions 522 and the clamping ring 51 and then approach each other, making it easier for the two clamping blocks 52 to be inserted into the clamping ring 51. When the two clamping blocks 52 are moved as a whole to the predetermined position, the two guide parts 522 of the two clamping blocks 52 are disengaged from the abutment with the clamping ring 51, and the two elastic parts 521 of the two clamping blocks 52 return to their initial state. The two clamping parts 523 are close to the side of the segment tube 21 that supports itself and abut against the side of the clamping ring 51 that faces away from the segment tube 21 to be connected, thereby achieving a stable connection between the two segment tubes 21. The two end faces of the second annular airbag 53 are sealed against the two end faces of the two segment tubes 21 that are close to each other, playing the role of sealing the connection gap between the two segment tubes 21, ensuring that water will not leak from the connection of the segment tubes 21 during the water injection test. When the segment tubes 21 are removed, the clamping parts 523 will not be disengaged from the abutment with the clamping ring 51, and pulling up the first segment tube 21 at the top can pull up all other segment tubes 21. When the segment pipe 21 is completely pulled out of the base hole 100 , the clamping ring 51 can be removed by loosening the screws 7 fixing the clamping ring 51 on the segment pipe 21 , so as to facilitate the rapid separation of the segment pipes 21 .

[0043] Reference Figure 1 and Figure 3 In this embodiment, the second annular airbag 53 can expand and deform radially after being compressed along its own axial direction, and can restore its original shape after the pressure is released. The outer diameter of the first annular airbag 3 after being compressed and deformed is larger than the aperture of the non-test section 101 of the base hole 100. The outer diameter of the second annular airbag 53 in the initial state is smaller than the aperture of the test section 102 of the base hole 100, so that it can be placed into the base hole 100 together with the segment tube 21. The outer diameter of the second annular airbag 53 after being compressed and deformed is larger than the aperture of the test section 102 of the base hole 100. When the two segment tubes 21 are vertically connected, the segment tube 21 located above can use its own weight to squeeze the second annular airbag 53 to deform it.

[0044] In this way, when the two segmented pipes 21 are vertically connected, the upper segmented pipe 21 uses its own weight to axially squeeze the second annular airbag 53, causing it to expand and deform radially until the side wall of the second annular airbag 53 is sealed against the wall of the test section 102 of the base hole 100. The gap between the wall-protecting flower pipe 2 and the wall of the base hole 100 is divided into multiple sections, shortening the flow path of water flowing along the gap to flush the wall during water seepage, reducing the scouring of sediment on the wall by water flow, thereby reducing the risk of wall collapse and the sediment content in the water, and improving the accuracy of the test results of the permeability coefficient of the rock and soil layer in the test section 102. At the same time, due to the elastic properties of the second annular airbag 53, there is a certain axial elastic activity margin between the segmented pipes 21 and the segmented pipes 21, and there is also a certain radial activity margin between the segmented pipes 21 and the wall of the base hole 100. In actual use, when encountering position changes caused by slight external vibrations or other factors, this margin of movement can act as a buffer, reducing damage that may be caused by the rigid connection, and improving the stability of the connection between the segment tubes 21 and between the segment tubes 21 and the base hole 100. When the segment tube 21 is removed, the second annular airbag 53 can automatically shrink to its original state after the segment tube 21 is pulled up, preventing friction with the wall of the base hole 100 and preventing the removal of the segment tube 21.

[0045] Reference Figure 1 and Figure 2 In this embodiment, the segmented assembly 6 includes a first segmented airbag 61, a second segmented airbag 62, an air pump 63, and a connecting pipe 64. The first segmented airbag 61 and the second segmented airbag 62 are both made of rubber; the first segmented airbag 61 and the second segmented airbag 62 both have an expanded state with gas filled inside, and a contracted state with a hollow interior. When the first segmented airbag 61 and the second segmented airbag 62 are in the contracted state, their outer diameters are both smaller than the inner diameter of the clamping ring 51; when the first segmented airbag 61 and the second segmented airbag 62 are in the expanded state, their outer diameters are both larger than the inner diameter of the segmented tube 21. The first segmented airbag 61 is annular, and the second segmented airbag 62 is cylindrical. The connecting pipe 64 can be made of a stainless steel tube or a plastic tube; the first segmented airbag 61, the second segmented airbag 62, and the segmented tube 21 can all be movably arranged in a plurality of segmented tubes 21 connected end to end. The first segmented airbag 61 is sleeved onto the outer wall of the connecting tube 64, with its inner annular wall in sealed contact with the outer wall of the connecting tube 64. The first segmented airbag 61 is positioned above the second segmented airbag 62. An air pump 63 is used to inflate the first and second segmented airbags 61, 62. After expansion, the first and second segmented airbags 61, 62 block different locations of the segmented tube 21, forming an independent test cavity 211 within the first and second segmented airbags 61, 62, and the multiple segmented tubes 21. The connecting tube 64 is in communication with the test cavity 211, allowing water to be injected into the test cavity 211 through the connecting tube 64.

[0046] In this way, the first segmented airbag 61 and the second segmented airbag 62 are moved to different positions within multiple segmented tubes 21 connected end to end. Air is then inflated using an air pump 63 to block the segmented tubes 21 after expansion, thereby forming independent test cavities 211 within the multiple segmented tubes 21. Water is then injected into the test cavities 211 through the connecting tube 64, allowing permeability tests to be performed on the rock and soil layers of the test sections 102 at different locations, thereby improving the flexibility and specificity of the tests. It should be emphasized that due to the influence of the location of the seepage holes 23 on the segmented tubes 21, the blocking position of the first segmented airbag 61 and the second segmented airbag 62 must be maintained at the connection between the two segmented tubes 21.

[0047] Reference Figure 3 and Figure 4 In this embodiment, the outer wall of the second annular airbag 53 is provided with a first skirt 531 and a second skirt 532 made of rubber. The first skirt 531 and the second skirt 532 are annular in shape. The inner ends of the first skirt 531 and the second skirt 532 are both connected to the outer wall of the second annular airbag 53. The outer ends of the first skirt 531 and the second skirt 532 extend toward the segmented tube 21 near the ends of the second annular airbag 53. In this way, in the initial state of the second annular airbag 53, the outer edges of the first skirt 531 and the second skirt 532 are both located within the circumferential surface of the outer tube wall of the segmented tube 21. When the second annular airbag 53 is subjected to axial pressure, the outer edges of the first skirt 531 and the second skirt 532 can approach each other and abut against the wall of the base hole 100, thereby enhancing the sealing of the connecting gap between the two segmented tubes 21. The greater the test water pressure, the tighter the first skirt 531 and the second skirt 532 abut against the wall of the base hole 100 , and the better the sealing performance.

[0048] The working principle of the test device for water injection testing in the embodiment of the present application is as follows: after the non-test section 101 of the base hole 100 is drilled, the end of the wall protection tube 1 equipped with the first annular airbag 3 is directed downward, and the wall protection tube 1 is installed in the non-test section 101 of the base hole 100. The test section 102 of the base hole 100 is then drilled. The wall protection tube 1 can prevent the rock and soil layer in the non-test section 101 from collapsing. During the process, since the drilling of the test section 102 must be carried out within the wall protection tube 1, an annular boss is formed within the base hole 100 between the non-test section 101 and the test section 102. After the wall protection tube 1 is installed, the end of the first annular airbag 3 facing away from the wall protection tube 1 abuts against the annular boss. At this time, the weight of the wall protection tube 1 is used to axially squeeze the first annular airbag 3, which can cause the first annular airbag 3 to expand and deform radially and then seal against the wall of the non-test section 101 of the base hole 100, effectively blocking the gap between the wall protection tube 1 and the wall of the non-test section 101 of the base hole 100, preventing water in the rock and soil layer of the non-test section 101 from penetrating into the wall protection flower tube 2, and improving the accuracy of the permeability coefficient test results of the rock and soil layer of the test section 102. Subsequently, after the test section 102 of the base hole 100 is drilled, the end of the wall protection flower tube 2 with the abutment ring 22 is facing upward, and the wall protection flower tube 2 is installed in the test section 102 of the base hole 100, preventing the rock and soil layer of the test section 102 from collapsing and allowing the water injected into the wall protection flower tube 2 to directly contact the rock and soil layer of the test section 102 through the seepage holes 23. Finally, water is drawn from an external source by a water pump 41 and input into the wall-protecting flower tube 2 through a water injection pipe 42 to provide a water source for the water injection test; a flow meter 43 monitors the water flow in the water injection pipe 42, and a water level monitor 44 monitors the water level in the wall-protecting flower tube 2, and the data of the two are analyzed and calculated by the control host 45, so as to accurately test the permeability coefficient of the rock and soil layer of the test section 102. During the test, the first segmented airbag 61 and the second segmented airbag 62 are moved to different positions in a plurality of segmented pipes 21 connected end to end, and are inflated by an air pump 63 to expand them and then block the segmented pipe 21, thereby forming an independent test cavity 211 in the plurality of segmented pipes 21, and water is injected into the test cavity 211 through a connecting pipe 64, so that the permeability coefficient of the rock and soil layers of the test sections 102 at different positions can be tested separately, thereby improving the flexibility and pertinence of the test. After the test is completed, the wall-protecting tube 1 is pulled up and removed using a tube pulling machine. At this time, the first annular airbag 3 returns to its original shape after the pressure is released, reducing friction with the wall of the base hole 100. At the same time, due to the design of the limiting convex ring 11 and the abutment ring 22, when the wall-protecting tube 1 is pulled up, the wall-protecting flower tube 2 can be pulled up together, greatly improving the convenience and efficiency of removing the wall-protecting flower tube 2. Furthermore, this test device does not require the installation of an additional inflation device, nor does it require the complex inflation and deflation operations of the first annular airbag 3, reducing the complexity and cost of the water injection test operation.

[0049] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A testing device for water injection test, characterized in that: include: A wall protection tube (1) is arranged in a non-test section (101) of the base hole (100), and one end of the wall protection tube (1) is provided with a limiting convex ring (11) protruding from the inner tube wall thereof; A wall-protecting flower tube (2) is arranged in the test section (102) of the base hole (100); an abutting ring (22) is provided on the outer tube wall of the wall-protecting flower tube (2), which protrudes from the outer tube wall and is used to abut against the limiting convex ring (11); a plurality of water seepage holes (23) are opened through the tube wall of the wall-protecting flower tube (2); The first annular airbag (3) is sealed against the bottom end surface of the wall protection tube (1); the first annular airbag (3) can expand and deform in the radial direction after being compressed in the axial direction, and can restore the original shape after the pressure is released; the outer diameter of the first annular airbag (3) in the initial state is smaller than the aperture of the non-test section (101) of the base hole (100); the outer diameter of the first annular airbag (3) after being compressed and deformed is larger than the aperture of the non-test section (101) of the base hole (100); The test assembly (4) is used to inject water into the wall protection flower tube (2) to test the permeability coefficient of the rock and soil layer in the test section (102).

2. A testing device for water injection test according to claim 1, characterized in that: The test assembly (4) includes a water pump (41), a water injection pipe (42), a flow meter (43), a water level monitor (44) and a control host (45); the water pump (41) is used to extract water from an external source and input it into the wall-protecting flower tube (2) through the water injection pipe (42); the flow meter (43) is arranged on the water injection pipe (42) to monitor the water flow of the water injection pipe (42); the water level monitor (44) is arranged in the wall-protecting flower tube (2) to monitor the water level in the wall-protecting flower tube (2); the control host (45) is electrically connected to the flow meter (43) and the water level monitor (44) to analyze and calculate the permeability coefficient of the rock and soil layer in the test section (102).

3. A testing device for water injection test according to claim 1, characterized in that: The inner diameter of the first annular airbag (3) after being compressed and deformed is smaller than the outer diameter of the wall-protecting flower tube (2).

4. A testing device for water injection test according to claim 1, characterized in that: It also includes a connecting assembly (5); the wall-protecting flower tube (2) includes a plurality of segmented tubes (21), and the plurality of segmented tubes (21) are sealed end to end through the connecting assembly (5).

5. A testing device for water injection test according to claim 4, characterized in that: The connecting assembly (5) comprises a clamping ring (51), at least two clamping blocks (52) and a second annular airbag (53); the clamping ring (51) is arranged on the inner tube wall of the segment tube (21) and protrudes from the inner tube wall of the segment tube (21); the two clamping blocks (52) are respectively arranged on both sides of one end of the segment tube (21) and are used to clamp and cooperate with the clamping ring (51) on another segment tube (21) to achieve end-to-end connection between multiple segment tubes (21); the second annular airbag (53) is arranged between the two segment tubes (21) and is used to seal the connection gap between the two segment tubes (21).

6. A testing device for water injection test according to claim 5, characterized in that: The clamping block (52) comprises an elastic portion (521), a guide portion (522) and a clamping portion (523); the elastic portion (521) can generate elastic deformation, one end of the elastic portion (521) is connected to the inner tube wall of the segment tube (21), and the other end extends out of the end of the segment tube (21); the guide portion (522) is arranged at the end of the elastic portion (521) away from the segment tube (21), and the guide portion (522) is wedge-shaped, with the narrow end of the wedge away from the segment tube (21) and the wide end close to the segment tube (21); the outer distance between the narrow ends of the two guide portions (522) of the two clamping blocks (52) is smaller than the inner diameter of the clamping ring (51), and the two clamping blocks (52) are spaced apart from each other. ) has a spacing between the wide ends of the two guide portions (522) greater than the inner diameter of the clamping ring (51); the clamping portion (523) is arranged on one side of the wedge-shaped wide surface of the guide portion (522); when the two segment tubes (21) are connected, the two end surfaces of the second annular airbag (53) respectively seal against the two end surfaces of the two segment tubes (21) that are close to each other; the two clamping blocks (52) on the first segment tube (21) are inserted into the clamping ring (51) of the second segment tube (21), and the side of the clamping portion (523) of the first segment tube (21) close to the first segment tube (21) abuts against the side of the clamping ring (51) of the second segment tube (21) that is away from the first segment tube (21).

7. A testing device for water injection test according to claim 6, characterized in that: The second annular airbag (53) can expand and deform in the radial direction after being compressed in the axial direction, and can restore its original shape after the pressure is released; the outer diameter of the second annular airbag (53) in the initial state is smaller than the outer diameter of the segmented tube (21), and the outer diameter of the second annular airbag (53) after being compressed and deformed is larger than the aperture of the test section (102) of the base hole (100); when the two segmented tubes (21) are vertically arranged and connected, the segmented tube (21) located on the upper side can use its own weight to squeeze the second annular airbag (53) to deform it.

8. A testing device for water injection test according to claim 7, characterized in that: The invention also includes a segmented component (6), wherein the segmented component (6) includes a first segmented airbag (61), a second segmented airbag (62), an air pump (63) and a connecting pipe (64), wherein the first segmented airbag (61) and the second segmented airbag (62) are movably arranged in a plurality of segmented tubes (21) connected end to end; the air pump (63) is used to inflate the first segmented airbag (61) and the second segmented airbag (62), so that the first segmented airbag (61) and the second segmented airbag (62) block the segmented tubes (21) at different positions after expansion, and form independent test cavities (211) in the plurality of segmented tubes (21); the connecting pipe (64) is connected to the test cavity (211), and water can be injected into the test cavity (211) through the connecting pipe (64).

9. A testing device for water injection test according to claim 8, characterized in that: A first skirt (531) and a second skirt (532) are provided on the outer side wall of the second annular airbag (53); the first ends of the first skirt (531) and the second skirt (532) are connected to the outer side wall of the second annular airbag (53); the second ends of the first skirt (531) and the second skirt (532) respectively extend toward the segment tube (21) close to the two ends of the second annular airbag (53); in the initial state of the second annular airbag (53), the first skirt (531) and the second skirt (532) are both located within the circumferential surface where the outer tube wall of the segment tube (21) is located; after the second annular airbag (53) is compressed in the axial direction, the second ends of the first skirt (531) and the second skirt (532) can approach each other and abut against the wall of the base hole (100).

10. The testing device for water injection test according to claim 6, characterized in that: The clamping ring (51) is detachably connected to the inner tube wall of the segment tube (21) via a screw (7) threadedly connected to the segment tube (21).

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