Testing device and method for grouting reinforcement in high-pressure dynamic water environment

Abstract

The invention relates to a test device and method for grouting reinforcement in a high-pressure dynamic water environment. Comprising a water injection pressurization system, a sample loading system, a grouting system, a constant temperature control system and a recording system, a to-be-grouted reinforcement sample is placed in the sample loading system, and pressure is applied to the sample when the sample loading system is grouted, so that the pressure of upper soil is simulated; the water injection pressurization system is nested on the outer side of the sample loading system and is sealed, and the water injection pressurization system is used for simulating the influence of water flow on the sample grouting effect in a dynamic water environment by adjusting water pressure and changing the water flowing speed and direction; the grouting system is connected with the sample loading system and is used for injecting slurry; the constant temperature control system is used for simulating the influence of temperature change on the grouting effect; the recording system is used for recording the trend that grout escapes along with water flow in the grouting process. The high-pressure dynamic water environment under the complex geological condition can be highly restored, and the accuracy and reliability of a grouting reinforcement simulation test are remarkably improved.

Description

Technical Field

[0001] The invention belongs to the technical field of grouting reinforcement test, and in particular relates to a test device and method for grouting reinforcement under a high-pressure dynamic water environment. Background Art

[0002] As a fast, efficient and economical engineering method, grouting technology has been widely used around the world and plays a vital role in improving the integrity and safety of the target structure. Especially in the field of reinforcement of underground soil and rock environment, grouting technology plays a pivotal role. With the acceleration of urbanization in recent years, the development and utilization of underground space has become increasingly frequent, which has triggered a series of new challenges that require reinforcement of underground soil. Especially in coastal areas and areas with abundant groundwater, changes in groundwater conditions have a significant impact on the effect of grouting reinforcement. The rise and fall of groundwater levels, changes in water flow velocity and different water quality may affect the permeability, curing effect and overall reinforcement performance of grouting materials. Therefore, before the implementation of grouting reinforcement projects, it is particularly important to accurately test and determine the performance of grouting slurry, which is not only related to the control of construction quality, but also directly related to the long-term safety and stability of engineering structures.

[0003] At present, there are many types of indoor grouting reinforcement test devices, most of which are designed for specific engineering practices. The existing grouting reinforcement test devices have the following main shortcomings:

[0004] (1) At present, most grouting reinforcement test equipment has a single sample environment and cannot truly reflect the evaluation of grouting effect under the influence of multiple fields such as groundwater pressure, water flow, temperature, and soil pressure;

[0005] (2) Most existing grouting reinforcement test equipment still requires the sample to be removed from the grouting equipment after grouting, which causes significant disturbance to the sample and makes it impossible to complete the curing and effect measurement in the original grouting environment;

[0006] (3) The existing grouting sleeve has a relatively simple hole for grouting, and the size of the seepage hole is fixed and cannot be adjusted according to the sample conditions. In addition, the hole is not sealed, and the sand sample will suffer sample loss under the disturbance of grouting. Summary of the invention

[0007] The purpose of the present invention is to provide a test device and method for grouting reinforcement under a high-pressure dynamic water environment, which can simulate the actual situation of grouting reinforcement under a real high-pressure dynamic water state to the greatest extent and provide a theoretical basis for practical engineering applications.

[0008] The technical solution to achieve the purpose of the present invention is: a test device for grouting reinforcement under high-pressure dynamic water environment, including a water injection pressurization system, a sample loading system, a grouting system, a constant temperature control system and a recording system;

[0009] The sample to be reinforced by grouting is placed in the sample loading system, and the sample loading system applies pressure to the sample during grouting to simulate the upper soil pressure;

[0010] The water injection and pressurization system is nested outside the sample loading system and is sealed. The water injection and pressurization system simulates the influence of water flow on the sample grouting effect in a dynamic water environment by adjusting the water pressure and changing the water flow speed and direction.

[0011] The grouting system is connected to the sample loading system and is used to inject slurry;

[0012] The constant temperature control system is used to simulate the impact of temperature changes on grouting effects;

[0013] The recording system is used to record the tendency of slurry to escape with water flow during the grouting process.

[0014] Further, the water injection and pressurization system includes a clean water tank, a servo pressurized water pump, a water guide pipe, a transparent pressurized sleeve, an upper cover, a lower cover, a waste water tank, a water stop valve and a flow pressure sensor;

[0015] The pressure sleeve is sealed and connected with the upper cover and the lower cover. A group of water injection holes, a group of drainage holes and a group of water guide holes are arranged circumferentially on the pressure sleeve. By opening and closing different water injection holes, drainage holes and water guide holes, the servo pressure water pump, the water stop valve and the flow pressure sensor, the water pressure, water flow speed and direction in the pressure sleeve, i.e. the grouting environment, are changed.

[0016] Furthermore, the constant temperature control system includes a heating rod and a temperature controller; the heating rod is arranged in the clean water tank, and the water temperature in the clean water tank is accurately controlled by the temperature controller.

[0017] Furthermore, a group of water injection holes and a group of drainage holes on the circumference of the pressurized sleeve are arranged at 180°, and a group of water guide holes are arranged at 90° to a group of water injection holes and a group of drainage holes respectively; a group of water injection holes includes a plurality of water injection holes evenly arranged vertically along the pressurized sleeve, and each water injection hole is equipped with a three-way valve; a group of drainage holes includes a plurality of drainage holes evenly arranged vertically along the pressurized sleeve, and each drainage hole is equipped with a three-way valve; a group of water guide holes is used for water injection or drainage as needed, and a group of water guide holes includes a plurality of water guide holes evenly arranged vertically along the pressurized sleeve, and each water guide hole is equipped with a three-way valve.

[0018] Furthermore, the pressurizing sleeve is sealed and connected to the upper cover and the lower cover by a sealing rubber ring, and the upper cover and the lower cover are fastened by tie rods and bolts at four corners; the pressurizing sleeve is made of transparent acrylic material or transparent plexiglass material.

[0019] Further, the sample loading system includes a water-permeable sleeve, a water-permeable nut, a confining pressure throat clamp, a confining pressure regulating rod, an upper pressure rod, a lower pad and a confining pressure test device;

[0020] The side wall of the water-permeable sleeve is provided with threaded openings, and water-permeable nuts of different specifications are matched according to needs;

[0021] The lower pad is arranged in the water-permeable sleeve at the bottom of the sample, the upper pressure rod is provided with a grouting channel, and the sample is pressurized through the upper pressure rod;

[0022] The grouting confining pressure is controlled by the confining pressure throat hoop on the outside of the permeable sleeve, and the strain gauge of the confining pressure testing device is attached between the permeable sleeve and the confining pressure throat hoop; the confining pressure of the confining pressure throat hoop is controlled by the confining pressure adjusting rod.

[0023] Furthermore, the water-permeable sleeve is a spliced ​​piece composed of multiple sleeve petals, the sleeve petals are made of transparent acrylic material or transparent organic glass material, one end between adjacent sleeve petals is set as a concave surface, and the other end is set as a convex surface, the inner wall of the concave surface of the sleeve petal is chamfered inward, and the splicing of the sleeve petals is achieved by the cooperation of the concave and convex surfaces;

[0024] The confining pressure throat clamp is made of spring steel material, which clamps the water-permeable sleeve from the outside;

[0025] The upper pressure rod is made of spring steel and is located on the upper side of the specimen. It is used to simulate the upper soil pressure under the real grouting state by a uniaxial hydraulic press.

[0026] The lower pad is made of permeable stone material, and the excess slurry is discharged from the bottom of the grouting material;

[0027] The permeable nut includes a permeable nut outer ring and a permeable nut inner ring, and the permeable nut inner rings of permeable nuts of different specifications occupy different volumes;

[0028] The outer ring material of the permeable nut is made of acrylic material or plexiglass material, and the inner ring material of the permeable nut is made of permeable stone.

[0029] Further, the grouting system includes a slurry tank, an air compressor, a rotary motor and a stirring blade;

[0030] The slurry tank is used to load the evenly mixed grouting material. The air compressor injects compressed air into the slurry tank to form a maximum pressure of 10MPa, pushing the slurry at the bottom of the slurry tank through the water pipe to be injected into the sample to achieve pressurized grouting; the rotating motor drives the stirring blade to stir the grouting material;

[0031] Furthermore, the recording system is a high-speed camera, which uses the high-speed camera to record the tendency of the slurry to escape with the water flow during the grouting process through the transparent pressure sleeve and the permeable sleeve.

[0032] A method for performing a grouting reinforcement test using the above-mentioned test device comprises the following steps:

[0033] S1: Select the water-permeable nut and screw it into the corresponding position of the water-permeable sleeve, install the confining pressure hose clamp to the fixed position outside the water-permeable sleeve, and stick the strain gauge to the fixed position;

[0034] S2: The sample to be grout-reinforced is placed in a water-permeable sleeve, the upper pressure rod is installed on the upper part of the sample, placed in the pressurized sleeve, the upper cover is covered, and the fixing bolts are tightened; the upper pressure rod is pressurized by a uniaxial hydraulic press to reach the preset upper pressure;

[0035] S3: Turn on the servo pressure water pump to continuously inject water into the clean water tank, open the valve of the corresponding water injection hole, and reach the preset water pressure and flow rate; turn on the constant temperature control system to heat the clean water tank so that the water injection temperature reaches the preset temperature;

[0036] S4: Pour the set proportion of grouting material and water into the slurry tank. After the slurry is mixed, turn on the air compressor to inject compressed air into the slurry tank. Use the pressure gauge above the slurry tank to control the grouting pressure. When the preset grouting pressure is reached, open the grouting valve to start grouting. The slurry is injected into the center of the sample through the grouting hole in the upper pressure rod.

[0037] S5: Observe the loss of slurry from each water-permeable hole after grouting through the transparent pressure sleeve; stop grouting the sample after the sample reaches a stable state;

[0038] S6: Different curing methods are used for the samples according to different actual working conditions;

[0039] S7: After the curing is completed, the samples are subjected to in-situ mechanical property tests and permeability tests according to the working conditions.

[0040] Compared with the prior art, the present invention has the following significant advantages:

[0041] 1. The present invention designs a grouting reinforcement test equipment that can truly simulate the coupled interactive effects of multiple fields such as groundwater pressure, water flow, temperature, soil pressure, etc., and allows the specimens to be directly maintained and the effect tested in the original grouting environment, effectively avoiding the interference that may occur during the sample removal process, and providing a more reliable basis for engineering practice.

[0042] 2. The present invention designs an adjustable grouting sleeve with perforated holes. The size of the seepage holes of the sleeve can be flexibly adjusted according to the sample conditions, and a sealing device is provided in the hole. The present invention can effectively prevent the loss of sand samples under grouting disturbance, which not only improves the controllability of the grouting process, but also further ensures the accuracy and stability of the test results.

[0043] 3. The present invention innovatively proposes a new type of grouting effect evaluation technology, which can accurately reflect the grouting process under complex geological environments, calculate the effective grouting volume of slurry, and observe the seepage of grouting materials through a transparent sleeve, thereby more intuitively and accurately evaluating the grouting effect through multiple factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the overall structure of the test device of the present invention;

[0045] Figure 2 It is a schematic diagram of the three-dimensional structure of the grouting part of the present invention;

[0046] Figure 3 It is a cross-sectional view of the pressurized sleeve of the present invention;

[0047] Figure 4 It is a cross-sectional view of the water-permeable sleeve of the present invention;

[0048] Figure 5 A three-dimensional schematic diagram of the water-permeable sleeve petal of the present invention;

[0049] Figure 6 This is a schematic diagram of a water-permeable nut according to the present invention;

[0050] Figure 7 It is a schematic diagram of a series of water-permeable nuts of the present invention.

[0051] Description of reference numerals:

[0052] 1-1-clean water tank, 1-2-servo pressure water pump, 1-3-water pipe, 1-4-pressure sleeve, 1-5-upper cover, 1-6-lower cover, 1-7-waste water tank, 1-8-water stop valve, 1-9-flow pressure sensor, 2-1-permeable sleeve, 2-2-permeable nut, 2-3-confining pressure throat clamp, 2-4-confining pressure adjustment rod, 2-5-upper pressure rod, 2-6-lower gasket, 2-7-confining pressure test device, 2-8-permeable nut outer ring, 2-9-permeable nut inner ring , 2-10-grouting channel, 2-11-first water injection hole, 2-12-second water injection hole, 2-13-third water injection hole, 2-14-first water guide hole, 2-15-second water guide hole, 2-16-third water guide hole, 2-17-first drainage hole, 2-18-second drainage hole, 2-19-third drainage hole, 3-1-slurry tank, 3-2-air compressor, 3-3-rotating motor, 3-4-stirring blade, 4-1-heating rod, 4-2-temperature controller, 5-sample. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present application to provide a detailed and clear description of the technical solution. It should be clear that the embodiments only represent some examples of the present application, not all of them. Based on these embodiments, all other implementation methods that can be derived by those skilled in the art without creative work are deemed to fall within the scope of protection of the present application.

[0054] In this document, the term "embodiment" is used to indicate that a particular feature, structure, or property described in conjunction with its example may be embodied in at least one embodiment of the present application. When the phrase appears in different places in the text, it does not necessarily refer to the same embodiment, nor does it mean that it is mutually exclusive, independent, or alternative to other embodiments. It should be clearly understood by those skilled in the art that the embodiments described herein can be flexibly combined with other embodiments.

[0055] Embodiment 1:

[0056] See also Figure 1-6 The present invention provides a test device for grouting reinforcement under high-pressure dynamic water environment, including a water injection pressurization system, a sample loading system, a grouting system and a constant temperature control system; wherein the water injection pressurization system mainly simulates the influence of water flow on the grouting effect of the sample under a dynamic water environment by increasing water pressure and changing water flow speed and direction; wherein the influence of the environment on the grouting effect of the sample under a deep soil pressure environment is simulated; wherein the grouting system increases the pressure by an air compressor to pump the grouting material through a water pipe to grout the sample; wherein the constant temperature control system mainly controls the heating plate through a temperature controller to simulate the influence of temperature changes on the grouting effect;

[0057] The water injection and pressurization system includes a clean water tank 1-1, a servo pressurized water pump 1-2, a water guide pipe 1-3, a pressurized sleeve 1-4, an upper cover 1-5, a lower cover 1-6, a waste water tank 1-7, a water stop valve 1-8 and a flow pressure sensor 1-9;

[0058] The sample loading system includes a water-permeable sleeve 2-1, a water-permeable nut 2-2, a confining pressure throat clamp 2-3, a confining pressure regulating rod 2-4, an upper pressure rod 2-5, a lower cushion block 2-6 and a confining pressure testing device 2-7;

[0059] The grouting system includes a slurry tank 3-1, an air compressor 3-2, a rotary motor 3-3 and a stirring blade 3-4;

[0060] The constant temperature control system includes a heating rod 4-1 and a temperature controller 4-2.

[0061] The clean water tank 1-1 is continuously supplied with water through the servo pressure pump 1-2 to increase its internal pressure; when the preset water pressure value is reached, the water stop valve 1-8 opens to allow water to flow into the pressure sleeve 1-4; the water then flows through the sample loading system and finally flows into the waste water tank 1-7. The water pipes in the entire water injection and pressure system are equipped with water stop valves 1-8 and flow pressure sensors 1-9 to achieve precise control and real-time monitoring of the water flow state.

[0062] The water-permeable sleeve 2-1 is located inside the pressurized sleeve 1-4; the upper cover 1-5 and the lower cover 1-6 are located outside the pressurized sleeve 1-4 and are tightened with bolts, and the connection is sealed by a sealing rubber ring.

[0063] The pressurized sleeves 1-4 are provided with a plurality of water injection holes, drainage holes and water guide holes, and the flexible regulation of the water flow direction is achieved by precisely controlling the opening and closing states of the corresponding valves.

[0064] The water-permeable sleeve 2-1 is constructed as a splicable structure composed of multiple sleeve petals, one end of each sleeve petal is designed as a concave interface, and the other end is designed as a matching convex interface; wherein the inner wall of the concave interface is provided with an inward chamfer so that when confining pressure is applied, the sleeve can achieve a certain degree of radial contraction through the tight fit between the petals.

[0065] The grouting confining pressure is controlled by the confining pressure throat hoop 2-3 on the outside of the water-permeable sleeve 2-1, and the strain gauge of the confining pressure testing device 2-7 is posted between the water-permeable sleeve 2-1 and the confining pressure throat hoop 2-3.

[0066] The water-permeable sleeve 2-1 is provided with threaded openings and is equipped with corresponding water-permeable nuts.

[0067] The outer ring 2-8 of the permeable nut is made of transparent material, and the inner ring 2-9 of the permeable nut is made of permeable stone material; in addition, the permeable nut is designed with various specifications to adapt to and match the permeability requirements under different actual working conditions.

[0068] The grouting system is equipped with a closed slurry tank 3-1, which is used to load the uniformly matched grouting material; and also includes an air compressor 3-2, which injects compressed air into the slurry tank 3-1 to form a maximum pressure of 10MPa, thereby pushing the slurry at the bottom of the slurry tank to be forced into the sample 5 through the water pipe, thereby realizing the process of pressurized grouting;

[0069] In order to prevent the grouting material from segregating, the device is equipped with a rotating motor 3-3, which drives the stirring blades 3-4 through the transmission shaft to achieve effective stirring of the grouting material.

[0070] The constant temperature control system includes a heating rod 4-1 and a temperature controller 4-2;

[0071] The heating rods 4-1 are evenly arranged in the clean water tank to maintain the temperature of the water injection medium.

[0072] The temperature controller 4-2 is responsible for accurately monitoring and adjusting the working state of the above-mentioned heating rod to ensure that the dynamic water environment of the grouting sample can reach the preset constant temperature condition during the entire test process.

[0073] When assembling the test device of the present invention, the permeable stone of the lower pad 2-6 is properly placed at the bottom of the permeable sleeve 2-1. The pre-grouting reinforcement sample 5 is placed on the lower pad 2-6 and is tightly fixed to the periphery of the permeable sleeve 2-1 using the confining pressure hose clamp 2-3 to ensure stability and sealing during the test.

[0074] The strain gauge of the confining pressure test device 2-7 is precisely pasted between the water-permeable sleeve 2-1 and the confining pressure throat clamp 2-3, and the corresponding signal transmission line is carefully connected to monitor and record the strain changes during the test in real time.

[0075] The upper pressure rod 2-5 is accurately placed against the sample 5, and then the pressure sleeve 1-4 is placed on the outside of the water-permeable sleeve 2-1. To ensure the sealing and stability of the device, sealing rubber rings are placed at the upper and lower connections between the upper cover 1-5, the lower cover 1-6 and the pressure sleeve 1-4, and the bolts at the four feet of the device are used to evenly tighten and fix them.

[0076] The upper pressure rods 2-5 can be supported by a hydraulic press, and the hydraulic press can be used to provide axial pressure to simulate the upper soil pressure during the grouting process.

[0077] The servo pressure pump 1-2 is used to inject water into the clean water tank 1-1, and the water pressure in the clean water tank 1-1 can be increased to 10MPa at most. The corresponding control valves are opened and closed according to the settings of the experimental control group to simulate the flow direction of the water flow.

[0078] The pressurized water first flows through the permeable sleeve 2-1, and then the water flows through the specially set drainage holes, during which they mix with the grouting liquid that may escape. The mixed wastewater is then effectively discharged and finally collected in the wastewater tank 1-7.

[0079] Specifically, the water injection pressurization system can inject water into the pressurization sleeve 1-4 through the first water injection hole 2-11, the second water injection hole 2-12, the third water injection hole 2-13, the first water guide hole 2-14, the second water guide hole 2-15 and the third water guide hole 2-16; it can drain water to the waste water tank 1-7 through the first drainage hole 2-17, the second drainage hole 2-18, the third drainage hole 2-19, the first water guide hole 2-14, the second water guide hole 2-15 and the third water guide hole 2-16;

[0080] By selecting different combinations of holes for water injection and drainage operations, the flow direction of water in the pressurized sleeve can be flexibly adjusted. This flexibility not only simulates the impact of different water flow directions on the grouting effect, but also allows in-depth analysis for specific water flow conditions.

[0081] The water pipes outside each water hole are equipped with three-way valves, which not only control the inflow and outflow of water, but also accurately adjust the path and state of the water flow. By adjusting the direction of the valve, the path of the water flow can be easily opened, closed or changed, thereby achieving fine control of the direction of the water flow.

[0082] The temperature controller 4-2 is used to precisely adjust the temperature of the heating rod 4-1 and to control the temperature of the clean water tank 1-1. Through precise temperature setting and maintenance, the device can simulate the grouting environment under different temperature conditions, thereby comprehensively evaluating the performance of the grouting material and the grouting effect under different temperatures.

[0083] Put the grouting material with a preset water-cement ratio into the slurry box 3-1, start the rotating motor 3-3 to drive the stirring blade 3-4 through the transmission shaft to stir the slurry to prevent the grouting liquid from bleeding, segregation, etc.

[0084] Start the air compressor 3-2 to inject high-pressure air into the slurry tank 3-1, which can drive a grouting pressure of up to 10 MPa, and drive the mixed grouting liquid in the slurry tank 3-1 for grouting.

[0085] Embodiment 2:

[0086] The present invention provides a technical solution: a test method for grouting reinforcement under a high-pressure dynamic water environment, and the second embodiment is optimized on the basis of the first embodiment;

[0087] The loss of slurry during the grouting process can be observed through the transparent pressure sleeve 1-4 and the permeable sleeve 2-1. A high-speed camera can be used to record the trend of slurry escaping with water flow, and the influence of water flow direction on the grouting liquid escaping can be studied.

[0088] Based on the output of the clean water tank 1-1 and the slurry tank 3-1, and the increase of the waste water tank 1-7 and the sample 5, the effect of the grouting sample is evaluated.

[0089] During the sample curing stage, the present invention adopts a strategy of operating in the original grouting environment, by continuously injecting pressurized moving water into the pressure sleeve 1-4 and maintaining the axial pressure applied by the upper pressure rod 2-5 to ensure that the curing conditions are closer to the actual environment after grouting, thereby being able to more accurately simulate and evaluate the curing effect after grouting.

[0090] After the curing process is completed, the equipment supports direct in-situ pressure testing of the mechanical properties of sample 5. The specific operation includes adjusting the confining pressure hose clamp 2-3 to a loose state through the adjustment rod, and then applying gradually increasing pressure to sample 5 until sample 5 reaches the breaking strength, so as to accurately determine its strength after grouting reinforcement in the original environment.

[0091] It should be noted that the structural layout, proportional dimensions and specification parameters shown in the drawings of this patent are intended to assist in explaining the text content and facilitate professional and technical personnel to understand and analyze, rather than to constitute a strict limitation on the implementation methods of the present invention. Therefore, as long as the fine-tuning of the structure, the reasonable change of the proportional relationship or the appropriate expansion and contraction of the size range do not weaken the functional effect of the present invention or hinder the realization of the established goals, they should be deemed to fall within the scope of protection defined by the technical solution of the present invention. In addition, the directional expressions such as "up", "down", "left", "right", "center" and "single" used in the specification are only for the sake of clarity of explanation and are not used to frame the application boundaries of the present invention. On the premise of keeping the technical core unchanged, the relative changes or adaptive adjustments of the above-mentioned directional descriptions should also be regarded as reasonable extensions of the implementation methods of the present invention.

Claims

1. A test device for grouting reinforcement under high pressure water dynamic environment, characterized in that: Including water injection and pressurization system, sample loading system, grouting system, constant temperature control system and recording system; The sample to be reinforced by grouting is placed in the sample loading system, and the sample loading system applies pressure to the sample during grouting to simulate the upper soil pressure; The water injection and pressurization system is nested outside the sample loading system and is sealed. The water injection and pressurization system simulates the influence of water flow on the sample grouting effect in a dynamic water environment by adjusting the water pressure and changing the water flow speed and direction. The grouting system is connected to the sample loading system and is used to inject slurry; The constant temperature control system is used to simulate the impact of temperature changes on grouting effects; The recording system is used to record the tendency of slurry to escape with water flow during the grouting process.

2. The test device according to claim 1, characterized in that: The water injection and pressurizing system comprises a clean water tank (1-1), a servo pressurizing water pump (1-2), a water guide pipe (1-3), a transparent pressurizing sleeve (1-4), an upper cover (1-5), a lower cover (1-6), a waste water tank (1-7), a water stop valve (1-8) and a flow pressure sensor (1-9); The pressurizing sleeve (1-4) is sealedly connected to the upper cover (1-5) and the lower cover (1-6); a group of water injection holes, a group of drainage holes and a group of water guide holes are circumferentially arranged on the pressurizing sleeve (1-4); and the water pressure, water flow speed and direction in the pressurizing sleeve (1-4), i.e., the grouting environment, are changed by opening and closing the different water injection holes, drainage holes and water guide holes, a servo pressurizing water pump (1-2), a water stop valve (1-8) and a flow pressure sensor (1-9).

3. The test device according to claim 2, characterized in that: The constant temperature control system comprises a heating rod (4-1) and a temperature controller (4-2); the heating rod (4-1) is evenly arranged in the clean water tank (1-1), and the temperature controller (4-2) is used to control the water temperature in the clean water tank (1-1).

4. The test device according to claim 3, characterized in that: A group of water injection holes and a group of drainage holes on the circumference of the pressurizing sleeve (1-4) are arranged at 180 degrees, and a group of water guide holes are arranged at 90 degrees with the group of water injection holes and the group of drainage holes respectively; a group of water injection holes includes a plurality of water injection holes evenly arranged vertically along the pressurizing sleeve (1-4), and each water injection hole is equipped with a three-way valve; a group of drainage holes includes a plurality of drainage holes evenly arranged vertically along the pressurizing sleeve (1-4), and each drainage hole is equipped with a three-way valve; a group of water guide holes is used for water injection or drainage according to needs, and a group of water guide holes includes a plurality of water guide holes evenly arranged vertically along the pressurizing sleeve (1-4), and each water guide hole is equipped with a three-way valve.

5. The test device according to claim 4, characterized in that: The pressurizing sleeve (1-4) and the upper cover (1-5) and the lower cover (1-6) are sealed and connected via a sealing rubber ring, and the upper cover (1-5) and the lower cover (1-6) are fastened via tie rods and bolts at four corners; the pressurizing sleeve (1-4) is made of a transparent acrylic material or a transparent organic glass material.

6. The test device according to claim 5, characterized in that: The sample loading system comprises a water-permeable sleeve (2-1), a water-permeable nut (2-2), a confining pressure throat clamp (2-3), a confining pressure regulating rod (2-4), an upper pressure rod (2-5), a lower cushion block (2-6) and a confining pressure testing device (2-7); The side wall of the water-permeable sleeve (2-1) is provided with threaded openings, and water-permeable nuts of different specifications are matched according to needs; The lower cushion block (2-6) is arranged in the water-permeable sleeve (2-1) at the bottom of the sample (5), the upper pressure rod (2-5) is provided with a grouting channel (2-10), and the sample is pressurized through the upper pressure rod (2-5); The grouting confining pressure is controlled by a confining pressure throat hoop (2-3) outside the water-permeable sleeve (2-1); a strain gauge of a confining pressure testing device (2-7) is attached between the water-permeable sleeve (2-1) and the confining pressure throat hoop (2-3); and the confining pressure of the confining pressure throat hoop (2-3) is controlled by a confining pressure regulating rod (2-4).

7. The test device according to claim 6, characterized in that The water-permeable sleeve (2-1) is a spliced ​​piece composed of multiple sleeve petals, the sleeve petals are made of transparent acrylic material or transparent organic glass material, one end between adjacent sleeve petals is set as a concave surface, and the other end is set as a convex surface, the inner wall of the concave surface of the sleeve petal is chamfered inward, and the splicing of the sleeve petals is achieved by matching the concave and convex surfaces; The confining pressure throat hoop (2-3) is made of spring steel material and clamps the water-permeable sleeve (2-1) from the outside; The upper pressure rod (2-5) is made of spring steel and is located on the upper side of the specimen. It uses a single-axis servo hydraulic press to simulate the upper soil pressure under the actual grouting state. The lower pad (2-6) is made of permeable stone material, and the excess slurry is discharged from the bottom of the grouting material; The water-permeable nut (2-2) comprises a water-permeable nut outer ring (2-8) and a water-permeable nut inner ring (2-9), and the volumes occupied by the water-permeable nut inner ring (2-9) of water-permeable nuts (2-2) of different specifications are different; The material of the outer ring (2-8) of the water-permeable nut is acrylic material or organic glass material, and the material of the inner ring (2-9) of the water-permeable nut is permeable stone.

8. The test device according to claim 7, characterized in that: The grouting system comprises a slurry tank (3-1), an air compressor (3-2), a rotating motor (3-3) and a stirring blade (3-4); The slurry box (3-1) is used to load the uniformly mixed grouting material. The air compressor (3-2) injects compressed air into the slurry box (3-1) to form a maximum pressure of 10MPa, pushing the slurry at the bottom of the slurry box through the water pipe to be injected into the sample (5), thereby realizing pressurized grouting; the rotating motor (3-3) drives the stirring blade (3-4) to stir the grouting material.

9. The test device according to claim 8, characterized in that The recording system is a high-speed camera, which uses the high-speed camera to record the tendency of slurry to escape with water during the grouting process through a transparent pressure sleeve (1-4) and a water-permeable sleeve (2-1).

10. A method for conducting a grouting reinforcement test using the test device according to claim 9, characterized in that: The steps include: S1: Select the water-permeable nut and screw it into the corresponding position of the water-permeable sleeve, install the confining pressure hose clamp to the fixed position outside the water-permeable sleeve, and stick the strain gauge to the fixed position; S2: The sample to be grout-reinforced is placed in a water-permeable sleeve, the upper pressure rod is installed on the upper part of the sample, placed in the pressurized sleeve, the upper cover is covered, and the fixing bolts are tightened; the upper pressure rod is pressurized by a uniaxial hydraulic press to reach the preset upper pressure; S3: Turn on the servo pressure water pump to continuously inject water into the clean water tank, open the valve of the corresponding water injection hole, and reach the preset water pressure and flow rate; turn on the constant temperature control system to heat the clean water tank so that the water injection temperature reaches the preset temperature; S4: Pour the set proportion of grouting material and water into the slurry tank. After the slurry is mixed, turn on the air compressor to inject compressed air into the slurry tank. Use the pressure gauge above the slurry tank to control the grouting pressure. When the preset grouting pressure is reached, open the grouting valve to start grouting. The slurry is injected into the center of the sample through the grouting hole in the upper pressure rod. S5: Observe the loss of slurry from each water-permeable hole after grouting through the transparent pressure sleeve; stop grouting the sample after the sample reaches a stable state; S6: Different curing methods are used for the samples according to different actual working conditions; S7: After the curing is completed, the samples are subjected to in-situ mechanical property tests and permeability tests according to the working conditions.

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