Visual cross fracture flowing water grouting test device and method

Abstract

The invention is suitable for the technical field of rock grouting reinforcement, and relates to a visual crossed fracture flowing water grouting test device and method. A transparent soil material with soil force properties and hydraulic properties similar to those of natural soil such as an internal friction angle, a deformation characteristic and a flow boundary effect is adopted; the water flow and slurry flowing state in an actual stratum can be truly simulated, and the accuracy of a test result is remarkably improved; by means of the layered water injection design of the soil filling box, comprehensive observation of the grouting behavior rule of cross fractures in stratums in different water saturation states is achieved, and the influence of complex hydrological conditions on the grouting effect is effectively reproduced; and a tracer agent with observation advantages is introduced in the grouting process, so that the visual observation capability on the slurry diffusion path, the slurry diffusion range and the flow velocity change is greatly enhanced. According to the method, the diffusion path, the expansion range and the grouting effect of the grout in a deep crack and a large model can be visually observed, the grouting effect is greatly improved, and a scientific basis is provided for optimizing the grouting process and predicting the grouting effect.

Description

Technical Field

[0001] The invention belongs to the technical field of rock grouting reinforcement, and in particular relates to a visualized cross-crack dynamic water grouting test device and method. Background Art

[0002] The presence of cross cracks in the rock mass can significantly increase the permeability and hydraulic conductivity of the rock mass, while weakening the stability of the surrounding rock. Especially near the cross cracks, due to the stress concentration effect, it is easy to form a dominant water channel under water-rich conditions, thereby inducing geological disasters such as sudden water inrush. Grouting reinforcement is an effective measure to seal the cracks in the surrounding rock. The visual grouting test device and method can clearly display the diffusion process of slurry in cracks and strata under multiple working conditions through intuitive visualization means. Combined with the changes in pressure and displacement, the dynamic characteristics of the slurry such as flow path, diffusion range and speed under different grouting environments are analyzed in detail, providing a scientific basis for optimizing grouting process parameters and predicting grouting effects.

[0003] Existing cross-crack grouting visualization devices usually use transparent materials (such as plexiglass) as the main body of the test device, and simulate different types of cross-crack states by artificially depicting different cross-crack models or adjusting the crack replica film and replacing the silicone strip. Combined with instruments such as camera equipment, pressure sensors and flow meters, the visualization and data monitoring of the slurry flow behavior in the cross-cracks are realized. This method has the following limitations: First, it mainly focuses on the flow behavior of the slurry, ignoring the interaction between the grouting and the soil or rock mass, and the grouting process is usually non-in-situ testing, lacking the influence of ground stress, which may lead to deviations between the test results and the actual engineering conditions; second, although transparent materials can realize the visualization of the grouting process, in deeper cracks or large-scale models, it is difficult to clearly observe the expansion process of the slurry due to insufficient transparency; third, the existing device cannot accurately monitor the grouting behavior of cross-cracks in strata with different saturation states. The patent with announcement number CN103411751B provides a visual cross-crack dynamic water grouting test device, including a slurry collection device and a cross-crack platform, the cross-crack platform includes a support frame, a cross-crack test chamber arranged on the support frame, cross-cracks arranged on the inner wall of the cross-crack test chamber, a flow rate sensor arranged in the cross-crack test chamber, and a pressure sensor arranged in the cross-crack test chamber; it also includes a dynamic water supply device for injecting water into the cross-crack test chamber and a pneumatic grouting device for grouting into the cross-crack test chamber, and the cross-crack test chamber is connected to the slurry collection device. The transparent cavity of the device in this patent is made of glass material, which has the same disadvantages as the prior art.

[0004] Therefore, how to provide a method for visually and clearly observing the diffusion path and range of the slurry and improving the grouting effect of the slurry is an urgent problem to be solved by personnel in this technical field. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a visual cross-fracture dynamic water grouting test device to solve the problem of poor cross-fracture grouting effect in rock mass in the prior art; in addition, the present invention also provides a visual cross-fracture dynamic water grouting test method.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a visual cross-crack dynamic water grouting test device, comprising:

[0008] A simulation system, a water injection system and a grouting system; the simulation system includes a soil filling box, a permeable plate and a plurality of cylinders, the soil filling box includes a first soil filling part and a second soil filling part, the permeable plate and a plurality of cylinders are arranged in the second soil filling part, and a plurality of cylinders are arranged above the permeable plate; the water injection system includes a first water tank, a first pressure pump, a first frequency converter, a second water tank, a second pressure pump, a second frequency converter, a monitoring terminal and a moisture sensor, the first water tank, the first pressure pump, the first frequency converter, and the monitoring terminal are sequentially connected in communication, the first water tank is also connected to the first soil filling part and the second soil filling part respectively, the second water tank, the second pressure pump, the second frequency converter, and the monitoring terminal are sequentially connected in communication, The second water tank is also connected to the first filling part, and the monitoring terminal is also connected to the moisture sensor, which is arranged on the permeable plate; the grouting system includes a first slurry tank, a second slurry tank, a tracer storage tank, a controller, an automatic stirring barrel and a third pressure pump, the first slurry tank and the second slurry tank are both connected to one end of the automatic stirring barrel, the first slurry tank and the second slurry tank are also connected to the controller, the tracer storage tank is connected to one end of the automatic stirring barrel, the tracer storage tank is connected to the controller, the other end of the automatic stirring barrel is connected to the grouting hole on the permeable plate, and the automatic stirring barrel is also connected to the third pressure pump.

[0009] Furthermore, the simulation system also includes a waste liquid barrel, which is connected to the bottom of the first filling part.

[0010] Furthermore, the water injection system also includes a water distributor, which is arranged on the water-permeable plate and is connected to the first water tank.

[0011] Furthermore, it also includes the first water-stop valve, the second water-stop valve, the third water-stop valve, the fourth water-stop valve, the fifth water-stop valve, the sixth water-stop valve and the seventh water-stop valve, the first water-stop valve is arranged between the first water tank and the first backfill part, the second water-stop valve is arranged between the first water tank and the second backfill part, the third water-stop valve is arranged between the first slurry storage tank and the automatic stirring barrel, the fourth water-stop valve is arranged between the tracer storage tank and the automatic stirring barrel, the fifth water-stop valve is arranged between the second slurry storage tank and the automatic stirring barrel, the sixth water-stop valve is arranged between the second water tank and the first backfill part, and the seventh water-stop valve is arranged between the waste liquid barrel and the first backfill part.

[0012] Furthermore, it also includes a first electromagnetic flowmeter, a second electromagnetic flowmeter, a third electromagnetic flowmeter and a fourth electromagnetic flowmeter, the first electromagnetic flowmeter is arranged between the first water tank and the first filling part, the second electromagnetic flowmeter is arranged between the first water tank and the second filling part, the third electromagnetic flowmeter is arranged between the automatic stirring barrel and the permeable plate, and the fourth flowmeter is arranged between the second water tank and the first filling part.

[0013] Furthermore, the simulation system also includes a DAQ data collection card, one end of which is communicatively connected to the permeable plate, and the other end of which is communicatively connected to the monitoring terminal.

[0014] Furthermore, the simulation system also includes a high-precision camera, which is arranged on one side of the soil filling box.

[0015] Furthermore, the simulation system also includes a test base, and the soil filling box is placed on the test base.

[0016] Furthermore, the filling material used in the filling box is one or more of silica gel transparent soil and polyacrylate transparent soil.

[0017] In a second aspect, the present invention also provides a visual cross-fracture dynamic water grouting test method, comprising the following steps:

[0018] S10, pre-preparation: evenly apply lubricating and anti-adhesion materials around and on the bottom of the soil filling box, and smooth the surface of the soil filling box; the first water tank and the second water tank are pre-filled with calcium bromide solution having the same refractive index as the selected transparent soil material; the first slurry storage tank and the second slurry storage tank store corresponding test slurry raw materials; and the tracer storage tank stores the prepared tracer solution;

[0019] S20, soil filling step: first spread a layer of transparent soil at the bottom of the first soil filling part, and compact the soil, place the 3D printed cross-crack model horizontally on the bottom transparent soil, and fill the transparent soil layer by layer until the cross-crack model is completely covered by the transparent soil, and the filling height reaches the requirement of the first soil filling part;

[0020] S30, continue to complete the placement and filling of the second layer of unsaturated zone model according to step S20, then install a permeable board on the top of the soil in the first filling part, close the filling box, and evenly install cylinders on the top to simulate the ground stress in the actual stratum;

[0021] S40, water injection step: the monitoring terminal and the first frequency converter adjust the water flow rate and water pressure to simulate the recharge state of groundwater in different seasons or geological conditions, start the first pressure pump and open the built-in switch of the first water tank at the same time, open the first water stop valve, keep the second water stop valve closed, and transport water to the left water inlet of the first filling part through the pipeline, and monitor the pressure and flow of the water injection through the first electromagnetic flowmeter, repeat the same operation to use the second water tank, the second pressure pump, and the second frequency converter to inject water into the right water inlet of the first filling part, monitor the flow and pressure through the fourth electromagnetic flowmeter, and observe the water level rise during the water injection process until the first filling part is filled. The transparent soil layer of the filling part is saturated, the second water tank, the second pressure pump and the sixth water stop valve are closed, and the first water stop valve is closed to stop water injection into the first filling part, and the second water stop valve is opened to start water injection into the second filling part to simulate the infiltration of surface water, and the water is allowed to infiltrate evenly through the water divider and the permeable plate, and the pressure and flow are monitored by the second electromagnetic flowmeter, and the saturation state of the transparent soil of the second filling part is monitored by the moisture sensor. When the test design requirements are met, the second water stop valve is kept open, and the first water stop valve is opened, and the second water tank, the second pressure pump and the second frequency converter are opened at the same time, and the first filling part is injected with water again, and grouting is started;

[0022] S50, grouting step: according to the slurry material properties and test requirements, inject the slurry into the automatic stirring barrel through the controller and the monitoring terminal, and adjust the flow rate and flow velocity, and at the same time add the tracer in the tracer storage tank to the automatic stirring barrel for uniform mixing, start the third pressure pump, and inject the slurry containing the tracer into the top soil of the second fill part according to the set pressure, open the seventh water stop valve to simulate the groundwater discharge conditions under different conditions, monitor the pressure and flow during the grouting process through the third electromagnetic flowmeter, record the entire grouting process through a high-precision camera, connect the DAQ data collection card with multiple sensors arranged on the cross-cracks to collect the slurry pressure and flow at the entrance, intersection, and outlet of the cross-cracks and feed them back to the monitoring terminal, when the tracer diffuses to the preset range, or the slurry reaches the predetermined saturation, turn off the third pressure pump, turn off the high-precision camera at the same time, and end the grouting process;

[0023] S60, stone removal: fully open the seventh water stop valve at the bottom of the device, close all other water stop valves and water tanks, completely drain the water and waste liquid in the soil filling box into the waste liquid bucket, remove the stone, and ensure that it is not damaged, so as to facilitate subsequent observation of soil structure changes and verification of grouting effects;

[0024] S70. The key parameters of the grouting process are recorded by a high-precision camera and combined with subsequent data analysis to accurately restore the diffusion behavior of the slurry in the fractured medium.

[0025] Compared with the prior art, the visualized cross-crack dynamic water grouting test device and method provided by the present invention have at least the following beneficial effects:

[0026] Existing cross-fracture grouting visualization devices and methods have the following limitations: First, they mainly focus on the flow behavior of the slurry, ignoring the interaction between the grouting and the soil or rock mass, and the grouting process is usually an ex-situ test, lacking the influence of ground stress, which may lead to deviations between the test results and actual engineering conditions; second, although transparent materials can realize the visualization of the grouting process, in deeper cracks or large-scale models, it is difficult to clearly observe the expansion process of the slurry due to insufficient transparency; third, existing devices cannot accurately monitor the grouting behavior of cross-fractures in strata with different saturation states. The present invention adopts transparent soil materials with geomechanical and hydraulic properties similar to those of natural soil, such as internal friction angle, deformation characteristics, and flow boundary effect, which can truly simulate the water flow and slurry flow state in the actual stratum, and significantly improve the accuracy of the test results; through the layered water injection design of the fill box, a comprehensive observation of the cross-crack grouting behavior law in the stratum with different saturation states is achieved, and the influence of complex hydrological conditions on the grouting effect is effectively reproduced; the introduction of tracers with observation advantages during the grouting process greatly enhances the visualization observation ability of the slurry diffusion path, range and flow rate changes. The present invention can intuitively observe the diffusion path, expansion range and grouting effect of the slurry in deeper cracks and larger models, greatly improving the grouting effect, and providing a scientific basis for optimizing the grouting process and predicting the grouting effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the scheme of the present invention, a brief introduction is given below to the figures required for use in the description of the embodiments. Obviously, the figures described below are some embodiments of the present invention. For ordinary technicians in this field, other figures can be obtained based on these figures without paying any creative work.

[0028] Figure 1 A structural diagram of a visual cross-fracture dynamic water grouting test device provided by an embodiment of the present invention;

[0029] Figure 2A schematic diagram of the distribution of grouting ports and water injection ports of a permeable plate of a visual cross-crack dynamic water grouting test device provided by an embodiment of the present invention;

[0030] Figure 3 A cross-crack model 1 and a schematic diagram of sensor distribution of a visual cross-crack dynamic water grouting test device provided by an embodiment of the present invention;

[0031] Figure 4 A second cross-crack model and a schematic diagram of sensor distribution of a visual cross-crack dynamic water grouting test device provided by an embodiment of the present invention;

[0032] Figure 5 A schematic cross-sectional view of a soil filling box of a visualized cross-fracture dynamic water grouting test device provided by an embodiment of the present invention;

[0033] Figure 6 A flow chart of a visual cross-fracture dynamic water grouting test method provided by an embodiment of the present invention;

[0034] Attached mark: 101-filling box; 1011-first filling part; 1012-second filling part; 102-permeable board; 1021-water injection hole; 1022-grouting hole; 103-cylinder; 104-waste liquid bucket; 105-DAQ data collection card; 106-high-precision camera; 107-test base; 108-cross crack model one; 109-cross crack model two; 110-sensor; 201-first water tank; 202-first pressure pump; 203-first frequency converter; 204-second water tank; 205-second pressure pump; 206-second frequency converter; 20 7-monitoring terminal; 208-moisture sensor; 209-water distributor; 301-first slurry storage tank; 302-second slurry storage tank; 303-tracer storage tank; 304-controller; 305-automatic mixing barrel; 306-third pressure pump; 401-first water stop valve; 402-second water stop valve; 403-third water stop valve; 404-fourth water stop valve; 405-fifth water stop valve; 406-sixth water stop valve; 407-seventh water stop valve; 501-first electromagnetic flowmeter; 502-second electromagnetic flowmeter; 503-third electromagnetic flowmeter; 504-fourth electromagnetic flowmeter. DETAILED DESCRIPTION

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field of the present invention; the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. For example, the directions or positions indicated by the terms "length", "width", "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the drawings, which are only for the convenience of description and should not be understood as limitations on the present technical solution.

[0036] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions; the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish different objects rather than to describe a specific order. In the specification and claims of the present invention and the above-mentioned drawings, when an element is referred to as being "fixed to" or "mounted on" or "disposed on" or "connected to" another element, it may be directly or indirectly located on the other element. For example, when an element is referred to as being "connected to" another element, it may be directly or indirectly connected to the other element.

[0037] In addition, reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] The present invention provides a visual cross-crack dynamic water grouting test device, which is applied to the grouting reinforcement construction process of sealing surrounding rock cracks. The visual cross-crack dynamic water grouting test device comprises:

[0039] The simulation system comprises a soil filling box, a permeable plate and a plurality of cylinders, the soil filling box comprises a first soil filling part and a second soil filling part, the permeable plate and a plurality of cylinders are arranged in the second soil filling part, and a plurality of cylinders are arranged above the permeable plate; the water injection system comprises a first water tank, a first pressure pump, a first frequency converter, a second water tank, a second pressure pump, a second frequency converter, a monitoring terminal and a moisture sensor, the first water tank, the first pressure pump, the first frequency converter, and the monitoring terminal are sequentially connected in communication, the first water tank is also connected to the first soil filling part and the second soil filling part respectively, the second water tank, the second pressure pump, the second frequency converter, the monitoring terminal The two ends are connected in sequence for communication, the second water tank is also connected to the first filling part, the monitoring terminal is also connected in communication with the moisture sensor, and the moisture sensor is arranged on the permeable plate; the grouting system includes a first slurry tank, a second slurry tank, a tracer storage tank, a controller, an automatic stirring barrel and a third pressure pump, the first slurry tank and the second slurry tank are both connected to one end of the automatic stirring barrel, the first slurry tank and the second slurry tank are also connected in communication with the controller, the tracer storage tank is connected to one end of the automatic stirring barrel, the tracer storage tank is connected in communication with the controller, the other end of the automatic stirring barrel is connected to the grouting hole on the permeable plate, and the automatic stirring barrel is also connected in communication with the third pressure pump.

[0040] The present invention can intuitively observe the diffusion path, expansion range and grouting effect of slurry in deeper cracks and larger models, greatly improves the grouting effect, and provides a scientific basis for optimizing the grouting process and predicting the grouting effect.

[0041] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0042] The present invention provides a visual cross-crack dynamic water grouting test device, which is used in the grouting reinforcement construction process of sealing surrounding rock cracks. Figures 1 to 5 In this embodiment, the visual cross-crack dynamic water grouting test device includes:

[0043] Simulation system, water injection system and grouting system; the simulation system includes a filling box 101, a permeable plate 102 and four cylinders 103. The permeable plate 102 and the four cylinders 103 are arranged in the second filling part 1012. The four cylinders 103 are arranged above the permeable plate 102 to control and adjust the loading of ground stress during the test. The state of the rock and soil body under different ground stress conditions can be simulated by controlling the cylinder 103, and then the behavior of the grouting process under different pressure conditions can be observed, providing a real test environment for studying the grouting diffusion law under different ground stresses. The filling box 101 is made of high-strength transparent organic glass, which is convenient for observing the flow behavior of the slurry inside the entire model. It can accommodate cracks and transparent soil layers. In order to prevent fluid leakage, the filling box is equipped with high-efficiency sealing materials such as silicone sealing rings or rubber pads around to ensure that there is no water leakage during the test. The filling box 101 includes a first filling part 1011 and a second filling part 1012, which are used to simulate the stratum in a saturated state and to simulate the stratum conditions in a non-saturated state. After the filling is completed, a layer of permeable board 102 is first installed. The permeable board 102 is evenly provided with water injection holes 1021 and a grouting hole 1022 at the center to ensure that the water flow is evenly injected to avoid excessive concentration of water flow leading to soil damage, and the stability of the permeable board 102 is ensured by a fixing device, and finally the filling box 101 is closed;The water injection system includes a first water tank 201, a first pressure pump 202, a first frequency converter 203, a second water tank 204, a second pressure pump 205, a second frequency converter 206, a monitoring terminal 207 and a moisture sensor 208. The first water tank 201, the first pressure pump 202, the first frequency converter 203 and the monitoring terminal 207 are communicatively connected in sequence. The first water tank 201 is also connected to the first filling part 1011 and the second filling part 1012 respectively. The second water tank 204, the second pressure pump 205, the second frequency converter 206 and the monitoring terminal 207 are communicatively connected in sequence. The first frequency converter 203 and the second frequency converter 206 respectively adjust the rotation speeds of the first pressure pump 202 and the second pressure pump 205 to achieve precise control of water flow to meet the test requirements. The first frequency converter 203 and the second frequency converter 206 can adjust the water flow speed and pressure. Accurately simulate the water flow behavior and infiltration rate under different hydrological conditions, and automatically adjust the water flow according to the real-time data of the sensor 110 (such as water pressure, flow, etc.), so as to ensure the stability of the water flow during the test, avoid the test results affected by the fluctuation of the water flow, and thus improve the automation and accuracy of the test. The second water tank 204 is also connected to the first filling part 1011, and the monitoring terminal 207 is also connected to the moisture sensor 208 for communication. The moisture sensor 208 is arranged on the permeable plate 102. The moisture sensor 208 is used to measure the moisture content of the transparent soil in the second filling part 1012 and compare it with the saturated moisture content. Once the value displayed by the moisture sensor 208 is close to or reaches the saturated moisture content of the soil, it indicates that the soil is close to saturation. The data can be fed back to the monitoring terminal 207 to monitor the moisture content of the water injection process to meet different test requirements;The grouting system includes a first slurry storage tank 301, a second slurry storage tank 302, a tracer storage tank 303, a controller 304, an automatic stirring barrel 305 and a third pressure pump 306. The first slurry storage tank 301 and the second slurry storage tank 302 are both connected to one end of the automatic stirring barrel 305, and the first slurry storage tank 301 and the second slurry storage tank 302 are also connected to the controller 304 for communication. The tracer storage tank 303 is connected to one end of the automatic stirring barrel 305, and the tracer storage tank 303 is connected to the controller 304 for communication. The other end of the automatic stirring barrel 305 is connected to the grouting hole 1022 on the permeable plate 102, and the automatic stirring barrel 305 is also connected to the third pressure pump 306 for communication. The controller 304 includes two control areas, the first control area is used to adjust the flow rate and flow of the slurry, and the second control area is used to adjust the flow rate and flow of the tracer. When the grouting material is a single component, the first slurry storage tank 301 and the second slurry storage tank 302 store the same slurry. When the grouting material is a two-component grouting material, the first slurry storage tank 301 and the second slurry storage tank 302 store different slurries respectively. The controller 304 is connected to the monitoring terminal 207, and the flow rate and flow velocity can be adjusted according to the characteristics of the slurry and the test requirements. The tracer storage tank 303 is used to store the slurry tracer. For colorless slurry, sodium fluorescein or rhodamine B can be selected as the tracer. Sodium fluorescein emits bright green fluorescence under ultraviolet light, and rhodamine B emits red fluorescence. These two tracers have strong fluorescence characteristics and can clearly mark the flow trajectory of the slurry. When using sodium fluorescein and rhodamine B, it is necessary to select appropriate concentrations according to the test conditions to ensure that they provide sufficient tracing effects without interfering with the flow behavior of the slurry. For colored slurry, the fluorescence characteristics of sodium fluorescein or rhodamine B can be used for tracing under ultraviolet light: sodium fluorescein emits green fluorescence, and rhodamine B emits red or orange-red fluorescence. ;

[0044] In this embodiment, the size of the fill box 101 is 50cm×30cm×50cm (length×width×height), wherein the first fill part 1011 is 30cm high and the second fill layer is 20cm high; in some other embodiments, the size of the fill box 101 can be adjusted according to actual on-site needs.

[0045] In this embodiment, there are two slurry storage tanks; in some other embodiments, if there are multiple slurries, multiple slurry storage tanks can be set according to actual conditions.

[0046] In this embodiment, the monitoring terminal 207 is a computer; in some other embodiments, the monitoring terminal 207 may also be a communication device such as a tablet or a mobile phone according to the test site environment.

[0047] Further, in this embodiment, if Figure 1As shown, the simulation system further includes a waste liquid barrel 104, which is connected to the bottom of the first filling part 1011 through a pipeline for collecting test waste liquid.

[0048] Further, in this embodiment, if Figure 1 As shown, the water injection system further includes a water divider 209, which is disposed on the water permeable plate 102 and communicated with the first water tank 201, and is used to cooperate with the water permeable plate 102 to make water infiltrate evenly and avoid excessive flow rate.

[0049] Further, in this embodiment, if Figure 1 As shown, the test device also includes a first water stop valve 401, a second water stop valve 402, a third water stop valve 403, a fourth water stop valve 404, a fifth water stop valve 405, a sixth water stop valve 406 and a seventh water stop valve 407 for controlling the opening and closing of water flow. The first water stop valve 401 is arranged between the first water tank 201 and the first backfill part 1011, the second water stop valve 402 is arranged between the first water tank 201 and the second backfill part 1012, the third water stop valve 403 is arranged between the first slurry storage tank 301 and the automatic stirring barrel 305, the fourth water stop valve 404 is arranged between the tracer storage tank 303 and the automatic stirring barrel 305, the fifth water stop valve 405 is arranged between the second slurry storage tank 302 and the automatic stirring barrel 305, the sixth water stop valve 406 is arranged between the second water tank 204 and the first backfill part 1011, and the seventh water stop valve 407 is arranged between the waste liquid barrel 104 and the first backfill part 1011.

[0050] Further, in this embodiment, if Figure 1 As shown, the test device also includes a first electromagnetic flowmeter 501, a second electromagnetic flowmeter 502, a third electromagnetic flowmeter 503 and a fourth electromagnetic flowmeter 504 for monitoring the pressure and flow during the grouting process. The first electromagnetic flowmeter 501 is arranged between the first water tank 201 and the first backfill part 1011, the second electromagnetic flowmeter 502 is arranged between the first water tank 201 and the second backfill part 1012, the third electromagnetic flowmeter 503 is arranged between the automatic stirring barrel 305 and the permeable plate 102, and the fourth flowmeter 504 is arranged between the second water tank 204 and the first backfill part 1011.

[0051] Furthermore, in this embodiment, combined with Figures 1 to 5The simulation system also includes a DAQ data collection card 105, one end of which is connected to the permeable plate 102 for communication, and the other end of which is connected to the monitoring terminal 207 for communication. The DAQ data collection card 105 can collect in real time the flow, pressure and other data transmitted by various sensors 110 arranged on the cross-crack model 1 108 and the cross-crack model 2 109 during the test, and transmit the data to the monitoring terminal 207. The DAQ data collection card 105 supports multi-channel data synchronous acquisition, and has high sampling rate and low latency characteristics, which can ensure the accurate recording of real-time data during the test. Through seamless connection with the sensor 110, the system can process signals from different sensors 110 and effectively avoid signal interference.

[0052] Furthermore, in this embodiment, combined with Figures 1 to 5 The simulation system also includes a high-precision camera 106. The high-precision camera 106 is set on one side of the fill box 101. It can clearly capture the flow behavior of the slurry in the cracks, ensure the visualization of the dynamic process, and can be combined with the sensor 110 data to provide real-time feedback on the test situation, help observe the slurry diffusion path and flow speed, and optimize the grouting process. The high-precision camera 106 overcomes the limitation of insufficient transparency, especially in deep cracks or large models, to ensure the accuracy of the test results.

[0053] Further, in this embodiment, if Figure 1 As shown, the simulation system further includes a test base 107, and the soil filling box 101 is placed on the test base 107 to ensure the stability of the entire test device during the test.

[0054] Furthermore, in this embodiment, the fill material is selected as transparent soil with geomechanical and hydraulic properties similar to those of natural soil, such as internal friction angle, deformation characteristics, and flow boundary effect. By artificially configuring different porosities and permeabilities of transparent soil, the hydraulic properties of natural soil in different states can be simulated. At the same time, the mechanical properties of transparent soil, such as compressibility and strength, can also match those of natural soil, especially in saturated or partially saturated states. There are two main types of commonly used transparent soil: silica gel transparent soil and polyacrylate transparent soil. Silica gel transparent soil is suitable for simulating sandy soil or coarse-grained soil, and polyacrylate transparent soil is suitable for simulating In order to simulate clay or dense soil layers, in order to avoid observation errors caused by different refractive indices at the interface between the liquid phase and the solid phase, the water in the water injection system in this embodiment is replaced by calcium bromide solutions of different concentrations (which needs to be determined according to the material of the transparent soil selected, mainly to make the refractive index of the calcium bromide solution the same as that of the transparent soil). During the test, the above-mentioned transparent soil type can be selected according to the needs of simulating different strata in the test, and the soil particle size, permeability and other parameters can be adjusted according to the test parameters to ensure the uniformity and stability of the fill, thereby providing a reliable test basis for grouting tests under different fracture conditions.

[0055] Furthermore, in this embodiment, combined with Figures 1 to 5 In the 3D modeling software, according to the test requirements, the parameters such as the size, angle, intersection, opening and shape of the cracks are accurately set. By selecting transparent materials and using high-precision 3D printing technology, cross-crack model 1 108 and cross-crack model 2 109 are generated to simulate the crack characteristics under different geological conditions. To ensure clear observation of the grouting behavior in the cross-cracks, the size of the cracks is usually 30%-50% of the size of the fill box 101, but the size, opening and shape of the cracks can be flexibly adjusted according to the test requirements. The transparent material used has high mechanical strength and stability, and can simulate the complexity of cracks in real rock masses. By accurately controlling the geometric parameters of the cracks, the influence of different crack openings and intersection angles on the slurry flow can be effectively studied, providing more accurate test data for the analysis of grouting behavior.

[0056] In a second aspect, the embodiment of the present invention further provides a visual cross-crack dynamic water grouting test method, which is applied to a visual cross-crack dynamic water grouting test device, combined with Figures 1 to 6 The visual cross-crack dynamic water grouting test method comprises the following steps:

[0057] S10, pre-preparation: In order to facilitate the removal of the stone body after the test, lubricating and anti-adhesion materials can be evenly applied around and on the bottom of the filling box 101 to play a role in lubrication and anti-adhesion. When applying, it is necessary to ensure that the vaseline is evenly covered and avoid being too thick or too thin to ensure the uniformity of the lubrication effect. The coating should be completely dried or fixed before the test to avoid affecting the slurry flow or the accuracy of the data during the test. If conditions permit, the surface of the filling box 101 can also be smoothed to reduce the adhesion between the stone body and the box body, so as to facilitate the smooth removal of the stone body after the test. The first water tank 201 and the second water tank 204 are pre-filled with calcium bromide solution with the same refractive index as the selected transparent soil material. The first slurry storage tank 301 and the second slurry storage tank 302 store the corresponding slurry raw materials for the test, and the tracer storage tank 303 stores the prepared tracer solution.

[0058] S20, filling steps: first spread a layer of transparent soil at the bottom of the first filling part 1011, about 4cm to 6cm thick, and gently compact the soil to provide a stable bottom foundation for the crack model to avoid the position of the model from shifting during the filling process. Use a plastic plate to gently compact each layer of soil. After each filling, ensure that the soil layer is uniform and dense to ensure its stability and uniformity. Place the 3D printed cross-crack model horizontally above the bottom transparent soil to ensure that the angle and position of the crack meet the requirements of the experimental design. Slowly fill the transparent soil layer by layer until the cross-crack model is completely covered by the transparent soil. The thickness of each layer of soil is 2cm to 3cm. Each layer must be lightly pressed to ensure that each layer of soil is uniform and stable, and the filling height meets the requirements of the first filling part 1011.

[0059] S30. After completing the first layer of filling, continue to complete the placement and filling of the second layer of unsaturated zone model according to step S20, ensuring that each layer of soil is evenly compacted to maintain the stability and uniformity of the entire test model, and then install the permeable board 102 on the top of the soil in the first filling part 1011, and ensure that it is firmly fixed to ensure uniform injection of water. After the filling work is completed, close the filling box 101, and evenly install the cylinder 102 on the top, and fix the cylinder 102 with threads to simulate the ground stress in the actual stratum to ensure that the stress environment during the test meets expectations.

[0060] S40, water injection step: the monitoring terminal 207 and the first frequency converter 203 adjust the water flow rate and water pressure to simulate the recharge state of groundwater in different seasons or geological conditions, start the first pressure pump 202 and open the switch built into the first water tank 201 at the same time, open the first water stop valve 401, keep the second water stop valve 402 closed, and transport water to the left water inlet of the first filling part 1011 through the pipeline, and monitor the pressure and flow of the water injection through the first electromagnetic flowmeter 501, repeat the same operation to use the second water tank 204, the second pressure pump 205, and the second frequency converter 206 to inject water into the right water inlet of the first filling part 1011, monitor the flow and pressure through the fourth electromagnetic flowmeter 504, observe the water level rise during the water injection process, until the transparent soil layer of the first filling part 1011 is saturated, close the second water tank 204, and close the second water tank 205. 04. The second pressure pump 205 and the sixth water stop valve 406 are connected, and the first water stop valve 401 is closed to stop injecting water into the first fill part 1011. The second water stop valve 402 is opened to start injecting water into the second fill part 1012 to simulate the infiltration of surface water. The water can be evenly infiltrated through the water divider 209 and the permeable plate 102 to avoid excessive flow rate. The pressure and flow are monitored by the second electromagnetic flowmeter 502. The saturated state of the transparent soil in the second fill part 1012 is monitored by the moisture sensor 208. When the test design requirements are met, the second water stop valve 402 is kept open, and the first water stop valve 401 is opened. At the same time, the second water tank 204, the second pressure pump 205 and the second inverter 206 are opened to inject water into the first fill part 1011 again. Note that the water flow rate should not be too fast at the beginning, and then grouting is started.

[0061] S50, grouting step: according to the slurry material properties and test requirements, the slurry is injected into the automatic stirring barrel 304 through the controller 304 and the monitoring terminal 207, and the flow rate and flow velocity are regulated. At the same time, the tracer in the tracer storage tank 303 is added to the automatic stirring barrel 304 for uniform mixing. After the slurry is uniformly mixed according to the slurry properties, the third pressure pump 306 is turned on, and the slurry containing the tracer is injected into the top soil of the second filling part 1012 according to the set pressure. At the same time, according to the test design requirements, the seventh water stop valve 407 is opened to simulate the groundwater discharge conditions under different states, and the third electromagnetic flow pump 306 is used to control the groundwater discharge conditions under different conditions. The meter 503 monitors the pressure and flow rate during the grouting process to ensure that the slurry is injected into the top evenly and slowly to avoid uneven diffusion caused by excessive pressure. The entire grouting process is recorded by the high-precision camera 106. The DAQ data collection card 105 is connected to multiple sensors 110 arranged on the cross-cracks to collect the slurry pressure and flow rate at the entrance, intersection and exit of the cross-cracks and feed them back to the monitoring terminal 207. When the tracer diffuses to a preset range or the slurry reaches a predetermined saturation, the third pressure pump 306 is turned off, and the high-precision camera 106 is turned off at the same time to end the grouting process.

[0062] S60, stone removal: fully open the seventh water stop valve at the bottom of the device, close all other water stop valves and water tanks, completely drain the water and waste liquid in the filling box into the waste liquid bucket, use pliers and other tools to carefully remove the stone to ensure that it is not damaged, so as to facilitate subsequent observation of soil structure changes and verification of grouting effects.

[0063] S70. The key parameters of the grouting process, including flow rate, pressure and tracer diffusion path, are recorded by a high-precision camera 106. The diffusion behavior of the slurry in the fractured medium is accurately restored in combination with subsequent data analysis. Based on the diffusion trajectory of the tracer, the flow and diffusion pattern of the slurry inside the transparent soil is visualized, thereby quantitatively evaluating the grouting effect. By analyzing the influence of the fracture structure characteristics on the flow and diffusion law of the slurry, a scientific basis is provided for optimizing the grouting design and construction process.

[0064] The visualized cross-crack behavior grouting test device and method described in the above-mentioned embodiment, compared with the prior art, the existing cross-crack grouting visualization device and method have the following limitations: First, it mainly focuses on the flow behavior of the slurry, ignoring the interaction between the grouting and the soil or rock mass, and the grouting process is usually a non-in-situ test, lacking the influence of ground stress, which may lead to deviations between the test results and actual engineering conditions; second, although transparent materials can realize the visualization of the grouting process, in deeper cracks or large-scale models, due to insufficient transparency, it is difficult to clearly observe the expansion process of the slurry; third, the existing device cannot accurately monitor the grouting behavior of cross-cracks in strata with different saturation states. The present invention adopts transparent soil materials with geomechanical and hydraulic properties similar to those of natural soil, such as internal friction angle, deformation characteristics, and flow boundary effect, which can truly simulate the water flow and slurry flow state in the actual stratum, and significantly improve the accuracy of the test results; through the layered water injection design of the fill box, a comprehensive observation of the cross-crack grouting behavior law in the stratum with different saturation states is achieved, and the influence of complex hydrological conditions on the grouting effect is effectively reproduced; the introduction of tracers with observation advantages during the grouting process greatly enhances the visualization observation ability of the slurry diffusion path, range and flow rate changes. The present invention can intuitively observe the diffusion path, expansion range and grouting effect of the slurry in deeper cracks and larger models, greatly improving the grouting effect, and providing a scientific basis for optimizing the grouting process and predicting the grouting effect.

[0065] Obviously, the embodiments described above are only preferred embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific embodiments, or to perform equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of the present invention, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. A visual cross-crack dynamic water grouting test device, characterized in that: include: Simulation system, water injection system and grouting system; The simulation system comprises a soil-filling box, a water-permeable plate and a plurality of cylinders, the soil-filling box comprises a first soil-filling part and a second soil-filling part, the water-permeable plate and a plurality of cylinders are arranged in the second soil-filling part, and a plurality of cylinders are arranged above the water-permeable plate; The water injection system includes a first water tank, a first pressure pump, a first frequency converter, a second water tank, a second pressure pump, a second frequency converter, a monitoring terminal and a moisture sensor, wherein the first water tank, the first pressure pump, the first frequency converter and the monitoring terminal are sequentially connected in communication, the first water tank is also connected to the first filling part and the second filling part respectively, the second water tank, the second pressure pump, the second frequency converter and the monitoring terminal are sequentially connected in communication, the second water tank is also connected to the first filling part, the monitoring terminal is also connected in communication with the moisture sensor, and the moisture sensor is arranged on the permeable plate; The grouting system includes a first slurry storage tank, a second slurry storage tank, a tracer storage tank, a controller, an automatic stirring barrel and a third pressure pump. The first slurry storage tank and the second slurry storage tank are both connected to one end of the automatic stirring barrel, and the first slurry storage tank and the second slurry storage tank are also connected to the controller for communication. The tracer storage tank is connected to one end of the automatic stirring barrel, and the tracer storage tank is connected to the controller for communication. The other end of the automatic stirring barrel is connected to the grouting hole on the permeable plate, and the automatic stirring barrel is also connected to the third pressure pump for communication.

2. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The simulation system further includes a waste liquid bucket connected to the bottom of the first filling part.

3. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The water injection system further includes a water divider, which is disposed on the water-permeable plate and communicated with the first water tank.

4. A visual cross-crack dynamic water grouting test device according to claim 2, characterized in that: It also includes the first water-stop valve, the second water-stop valve, the third water-stop valve, the fourth water-stop valve, the fifth water-stop valve, the sixth water-stop valve and the seventh water-stop valve. The first water-stop valve is arranged between the first water tank and the first filling part, the second water-stop valve is arranged between the first water tank and the second filling part, the third water-stop valve is arranged between the first slurry storage tank and the automatic stirring barrel, the fourth water-stop valve is arranged between the tracer storage tank and the automatic stirring barrel, the fifth water-stop valve is arranged between the second slurry storage tank and the automatic stirring barrel, the sixth water-stop valve is arranged between the second water tank and the first filling part, and the seventh water-stop valve is arranged between the waste liquid barrel and the first filling part.

5. A visual cross-crack dynamic water grouting test device according to claim 2, characterized in that: It also includes a first electromagnetic flowmeter, a second electromagnetic flowmeter, a third electromagnetic flowmeter and a fourth electromagnetic flowmeter. The first electromagnetic flowmeter is arranged between the first water tank and the first filling part, the second electromagnetic flowmeter is arranged between the first water tank and the second filling part, the third electromagnetic flowmeter is arranged between the automatic stirring barrel and the permeable plate, and the fourth flowmeter is arranged between the second water tank and the first filling part.

6. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The simulation system also includes a DAQ data collection card, one end of which is communicatively connected to the water permeable plate, and the other end of which is communicatively connected to the monitoring terminal.

7. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The simulation system also includes a high-precision camera, which is arranged on one side of the soil filling box.

8. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The simulation system further comprises a test base, and the soil filling box is placed on the test base.

9. A visual cross-crack dynamic water grouting test device according to claim 1, characterized in that: The filling material used in the filling box is one or more of silica gel transparent soil and polyacrylate transparent soil.

10. A visual cross-crack dynamic water grouting test method, characterized in that: The following steps are involved: S10, pre-preparation: evenly apply lubricating and anti-adhesion materials around and on the bottom of the soil filling box, and smooth the surface of the soil filling box; the first water tank and the second water tank are pre-filled with calcium bromide solution having the same refractive index as the selected transparent soil material; the first slurry storage tank and the second slurry storage tank store corresponding test slurry raw materials; and the tracer storage tank stores the prepared tracer solution; S20, soil filling step: first spread a layer of transparent soil at the bottom of the first soil filling part, and compact the soil, place the 3D printed cross-crack model horizontally on the bottom transparent soil, and fill the transparent soil layer by layer until the cross-crack model is completely covered by the transparent soil, and the filling height reaches the requirement of the first soil filling part; S30, continue to complete the placement and filling of the second layer of unsaturated zone model according to step S20, then install a permeable board on the top of the soil in the first filling part, close the filling box, and evenly install cylinders on the top to simulate the ground stress in the actual stratum; S40, water injection step: the monitoring terminal and the first frequency converter adjust the water flow rate and water pressure to simulate the recharge state of groundwater in different seasons or geological conditions, start the first pressure pump and open the built-in switch of the first water tank at the same time, open the first water stop valve, keep the second water stop valve closed, and transport water to the left water inlet of the first filling part through the pipeline, and monitor the pressure and flow of the water injection through the first electromagnetic flowmeter, repeat the same operation to use the second water tank, the second pressure pump, and the second frequency converter to inject water into the right water inlet of the first filling part, monitor the flow and pressure through the fourth electromagnetic flowmeter, and observe the water level rise during the water injection process until the first filling part is filled. The transparent soil layer of the filling part is saturated, the second water tank, the second pressure pump and the sixth water stop valve are closed, and the first water stop valve is closed to stop water injection into the first filling part, and the second water stop valve is opened to start water injection into the second filling part to simulate the infiltration of surface water, and the water is allowed to infiltrate evenly through the water divider and the permeable plate, and the pressure and flow are monitored by the second electromagnetic flowmeter, and the saturation state of the transparent soil of the second filling part is monitored by the moisture sensor. When the test design requirements are met, the second water stop valve is kept open, and the first water stop valve is opened, and the second water tank, the second pressure pump and the second frequency converter are opened at the same time, and the first filling part is injected with water again, and grouting is started; S50, grouting step: according to the slurry material properties and test requirements, inject the slurry into the automatic stirring barrel through the controller and the monitoring terminal, and adjust the flow rate and flow velocity, and at the same time add the tracer in the tracer storage tank to the automatic stirring barrel for uniform mixing, start the third pressure pump, and inject the slurry containing the tracer into the top soil of the second fill part according to the set pressure, open the seventh water stop valve to simulate the groundwater discharge conditions under different conditions, monitor the pressure and flow during the grouting process through the third electromagnetic flowmeter, record the entire grouting process through a high-precision camera, connect the DAQ data collection card with multiple sensors arranged on the cross-cracks to collect the slurry pressure and flow at the entrance, intersection, and outlet of the cross-cracks and feed them back to the monitoring terminal, when the tracer diffuses to the preset range, or the slurry reaches the predetermined saturation, turn off the third pressure pump, turn off the high-precision camera at the same time, and end the grouting process; S60, stone removal: fully open the seventh water stop valve at the bottom of the device, close all other water stop valves and water tanks, completely drain the water and waste liquid in the soil filling box into the waste liquid bucket, remove the stone, and ensure that it is not damaged, so as to facilitate subsequent observation of soil structure changes and verification of grouting effects; S70. The key parameters of the grouting process are recorded by a high-precision camera and combined with subsequent data analysis to accurately restore the diffusion behavior of the slurry in the fractured medium.

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