A device and method for testing the water scouring resistance of a grouting material

Abstract

The application discloses a kind of grouting material dynamic water scouring test device and test method, test device includes water supply unit, steady flow unit, flowmeter, scouring test tank in sequence, and for the grouting equipment for being used to the grouting in scouring test tank, for measuring the thickness measuring unit of slurry thickness in scouring test tank;Steady flow unit includes shell, located the inlet end and outlet end of opposite sides of shell, and in the direction from inlet end to outlet end, buffer steady flow area, honeycomb straightener, rectifier net group and taper guide area are sequentially arranged;Inlet end is connected with water supply unit, and outlet end is connected with flowmeter.The application provides a kind of grouting material dynamic water scouring test device and test method, to solve the problem that flow velocity control is not stable in prior art, test result is disturbed by local flow field disturbance etc., to realize the purpose of stable simulation dynamic water scouring environment, reduce the disturbance of flow velocity fluctuation and flow field disturbance to test result.

Description

Technical Field

[0001] This invention relates to the field of erosion resistance testing of grouting materials, and specifically to a dynamic water erosion resistance testing device and method for grouting materials. Background Technology

[0002] In tunnel, mine, water conservancy and hydropower, underground space, and water-rich fractured strata remediation projects, grouting materials are commonly used for fracture filling, seepage sealing, and strata reinforcement. For water-rich fractures, fault fracture zones, karst channels, and highly permeable media, the injected grout is often placed in an environment of continuous water flow. Before the grout forms a stable solidification structure, the water flow will dilute, shear, strip, and transport the grout, leading to the loss of effective solid phase, displacement of deposition location, and discontinuity of the sealing body, ultimately reducing the effectiveness of water plugging and reinforcement.

[0003] Traditional methods for evaluating the performance of grouting materials mainly include fluidity tests, setting time tests, water separation rate tests, compressive strength tests, impermeability tests, and anti-dispersion tests in water. These methods can evaluate the basic working performance and hardened body properties of the grout, but most are static or quasi-static tests, which cannot accurately reflect the grout's scouring and migration, near-source deposition, thickness attenuation, and solid phase retention processes under continuous flowing water conditions. For water-rich fissure sealing projects, simply evaluating whether the grout has good fluidity, can set and harden, and has strength after hardening is insufficient; further assessment is needed to determine whether the grout can stably remain in the target area under water scouring.

[0004] Existing technologies include some erosion and dispersion resistance testing devices or methods. These devices or methods provide a basis for evaluating the erosion resistance of grouting materials, but they still have the following shortcomings:

[0005] First, the flow velocity control of some devices is not stable enough. It mainly relies on head difference or manual adjustment to achieve flow velocity control, lacking real-time flow monitoring and stable regulation, resulting in unstable test results and insufficient comparability between different batches of tests.

[0006] Second, after the water flows into the test tank, it is easy to form local jets, backflows or turbulence, which affects the initial deposition morphology of the slurry and causes the test results to be severely interfered with by local flow field disturbances, resulting in insufficient accuracy of the test results.

[0007] Third, existing evaluation methods focus on the residual total mass of the slurry after flushing, which makes it difficult to reflect the spatial distribution characteristics of the slurry within different distance ranges.

[0008] Fourth, existing test methods do not adequately consider the changes in moisture content of residual slurry after scouring. Most methods directly use wet mass to evaluate residual slurry, which is easily affected by differences in moisture content and cannot accurately reflect the true solid phase retention capacity of the slurry.

[0009] In conclusion, it is necessary to improve and optimize existing technologies. Summary of the Invention

[0010] This invention provides a dynamic water scouring resistance test device and test method for grouting materials, in order to solve the problems of unstable water flow velocity control and interference of test results by local flow field disturbances in the prior art, and to achieve the purpose of stably simulating the dynamic water scouring environment and reducing the interference of flow velocity fluctuations and flow field disturbances on the test results.

[0011] This invention is achieved through the following technical solution:

[0012] A dynamic water erosion resistance test device for grouting materials includes a water supply unit, a flow stabilization unit, a flow meter, and an erosion test tank connected in sequence, as well as grouting equipment for grouting into the erosion test tank and a friction thickness measurement unit for measuring the thickness of the grout in the erosion test tank.

[0013] The flow stabilizing unit includes a housing, an inlet end and an outlet end located on opposite sides of the housing, and a buffer flow stabilizing zone, a honeycomb rectifier, a rectifier network and a gradually narrowing flow guiding zone arranged sequentially along the direction from the inlet end to the outlet end; the inlet end is connected to the water supply unit and the outlet end is connected to the flow meter.

[0014] To address the problems of unstable water flow velocity control and interference with test results from local flow field disturbances in existing technologies, this invention first proposes a dynamic water scour resistance test device for grouting materials. The water supply unit provides the necessary water for the entire test, the flow stabilization unit weakens the pulsation and local jet caused by the water supply unit, and the water enters the scour test tank after being metered by a flow meter. The grouting equipment injects grout into the scour test tank, and after the scour test is completed, the friction thickness of the residual grout inside the scour test tank is measured by the friction thickness measurement unit.

[0015] This application can accurately measure the water flow rate through a flow meter, and based on this, perform feedback control on the water supply of the water supply unit, thereby realizing real-time monitoring and stable adjustment of the initial flow rate in the scouring test tank and reducing the impact of flow velocity fluctuations on the test results.

[0016] Furthermore, this application significantly enhances the current stabilization effect in the current stabilization unit through the synergistic cooperation of the buffer current stabilization zone, the cellular rectifier, the rectifier network, and the tapered guide zone. Specifically:

[0017] The water flow first enters the buffer steady flow zone, where the cross-sectional area of ​​the water flow suddenly expands and the local jet velocity decreases, initially weakening the pulsating pressure and inlet impact of the water flow pumped by the water supply unit. It then enters the honeycomb rectifier, where the honeycomb channels divide the water flow into multiple nearly parallel small-scale streams, which can suppress transverse velocity components, secondary flows, and large-scale vortices. After that, it enters the rectifier network, where multiple layers of rectifier network dissipate turbulence of different scales, making the velocity distribution tend to be uniform. Finally, it enters the tapering guide zone, which is used to smoothly transition the rectified water flow to the scouring test tank, reducing separation, backflow, and local acceleration caused by abrupt changes in cross-section. It can be seen that the flow stabilization unit of this application, through the coherent coordination of "weakening pulsation - eliminating vortices - reducing turbulence - smooth introduction", can reduce the impact of local disturbances at the inlet of the scour test tank on the slurry deposition, stripping and migration process, so that the water flow tends to be stable when entering the scour test tank, and the test results can accurately reflect the scour resistance performance of the grouting material itself, rather than the difference in the inlet flow field, thereby significantly reducing the interference of velocity fluctuations and flow field disturbances on the test results.

[0018] This application can be used for evaluating the dynamic water erosion resistance of geopolymer grouting materials, as well as ordinary cement-based grouts, quick-setting grouts, anti-dispersion grouts, chemical grouts, and other water-blocking and reinforcement materials.

[0019] Furthermore, the water supply unit includes a water storage tank, a water pump for drawing water from the water storage tank, and a filter device located at the water inlet of the water pump, with the output end of the water pump connected to the inlet end.

[0020] The water storage tank is used to store the test water; the water pump is used to provide a continuous and stable water flow; the filtration device is used to intercept fine particles that enter the water body during the flushing process, reducing the impact of particulate matter on the water pump, pipelines, and flow meter. Of course, the water pump used in this application has an adjustable displacement, which facilitates real-time adjustment based on feedback from the flow meter.

[0021] Furthermore, the width of the buffer flow stabilization zone is 1.2 to 2.5 times the width of the scouring test tank, and the height of the buffer flow stabilization zone is 1.2 to 3.0 times the height of the scouring test tank; a flow-blocking arc-shaped component is provided in the buffer flow stabilization zone, and the concave surface of the flow-blocking arc-shaped component faces the inlet end.

[0022] This design ensures that the width and height of the buffer flow stabilization zone are both greater than those of the scouring test tank. This is more conducive to reducing the local jet velocity and allows more water to temporarily remain within the buffer flow stabilization zone, ensuring a stable and constant pressure water supply to the downstream. The water flowing into the buffer flow stabilization zone first impacts the flow-blocking arc-shaped component and is then dispersed around by the concave surface of the buffer flow stabilization zone, preventing the water from directly scouring the downstream honeycomb rectifier.

[0023] Furthermore, the aperture ratio of the cellular rectifier is 70% to 95%, and it includes several polygonal channels; the axis of the polygonal channel is parallel to the line connecting the inlet end to the outlet end; the hydraulic diameter of the polygonal channel is 3 to 10 mm; and the length of the polygonal channel is 5 to 12 times the hydraulic diameter of the polygonal channel.

[0024] The honeycomb rectifier in this design has a high aperture ratio, and the polygonal channels on the honeycomb rectifier are relatively long, which helps to divide the water flow into more and more stable parallel streams, and more effectively suppress the generation of transverse velocity components, secondary flows and large-scale vortices.

[0025] Furthermore, the rectifier mesh group includes 2 to 5 layers of rectifier mesh distributed sequentially, and the opening ratio of the rectifier mesh is 40% to 80%; the mesh count of each rectifier mesh gradually increases from the inlet end to the outlet end.

[0026] By using multi-layered rectifier nets with gradually increasing mesh size, the water flow is dispersed step by step, which can better ensure that the flow velocity of the water passing through the rectifier net group tends to be uniform overall.

[0027] Furthermore, the scouring test tank includes an inlet and an outlet axially away from the inlet; it also includes a flow stabilizer plate detachably installed inside the scouring test tank, the flow stabilizer plate being located between the inlet and the grouting equipment, and the distance between the flow stabilizer plate and the grouting equipment being 150~600mm; the thickness of the flow stabilizer plate is 1~5mm, and it has several circular holes with a diameter of 2~6mm, and the opening rate is 35%~70%.

[0028] In this design, after the water flows into the scouring test tank, it first passes through a flow stabilizer plate. The flow stabilizer plate evenly distributes the water flow at its end, making the flow field before the grouting area more stable and dispersed. This prevents the water from forming uncontrollable turbulence or backflow before entering the scouring test tank and reaching the grouting area, significantly improving the accuracy of the test results. The flow stabilizer plate has a relatively low opening ratio, which reduces the interaction between the flow streams after passing through it. Furthermore, an excessively large distance between the flow stabilizer plate and the grouting equipment can lead to the plate's failure, while an excessively small distance can easily accelerate the initial water flow. Therefore, the preferred distance range of 150~600mm is defined in this design.

[0029] The flow stabilizer can be installed using any existing detachable connection method.

[0030] Furthermore, the scour test tank located downstream of the grouting equipment is divided into several sequentially adjacent test sections; each test section includes a bottom plate with a convex cross-section and a detachable mounting plate that is connected to the inner wall of the scour test tank and matches the lateral notches on both sides of the bottom plate.

[0031] For engineering applications, grouting materials not only need to be retained, but also need to form stable deposits near the injection point to prevent large-scale downstream migration. However, existing technologies mostly focus on the residual total mass of the grout after scouring, failing to reflect the spatial distribution characteristics of the grout over different distances, i.e., they cannot understand the downstream migration of the grout. To overcome this problem, this scheme divides the scouring test tank downstream of the grouting equipment into several sequentially adjacent test sections. Each test section has a base plate at the bottom. After the test, the residual grout on the corresponding base plate of each test section is collected, thus obtaining the grout deposition situation in different areas along the downstream direction, and thereby judging the deposition stability of the tested grouting material. Furthermore, this scheme can also obtain indicators such as total retention rate, segmented mass ratio, thickness distribution centroid, and influence range by measuring the thickness of the residual grout along the test path and collecting segmented dry mass. Therefore, this scheme can achieve the technical effect of determining whether the grouting material is concentrated near the injection point, which has a significant technical advantage over the existing technology that only judges the amount of scouring.

[0032] Furthermore, if conventional flat plates are used as the base plates, because they are sequentially adjacent and have no gaps between them and the tank walls, it is difficult to remove each base plate after the experiment for subsequent operations such as residual slurry collection and weighing. Forcibly removing them can easily interfere with adjacent base plates, and in severe cases, even cause residual slurry misalignment. Therefore, this design uses a convex-shaped base plate with spacer plates at both ends. During normal testing, the spacer plates occupy the convex sides; when it is necessary to remove the base plate, the spacer plates on both sides are removed, and the base plate is taken from the convex side area and lifted. This design overcomes the problems of inconvenient base plate removal and the risk of interference with adjacent base plates or slurry misalignment caused by forced removal, significantly improving the accuracy of subsequent analysis.

[0033] Furthermore, the grouting equipment is installed on a grouting positioning frame, which is equipped with a height adjustment device for adjusting the height of the grouting equipment and a horizontal adjustment device for adjusting the position of the grouting equipment along the axial direction of the scouring test trench; the output end of the grouting equipment faces downward and is connected to a connector and a grouting pipe in sequence.

[0034] The thickness measurement unit includes a sliding bracket that is slidably mounted on the scouring test tank along the axial direction, a plurality of distance sensors that are evenly installed on the sliding bracket, the distance sensors having a downward measuring direction; and an axial scale that is axially set on the bottom or wall of the scouring test tank.

[0035] During their research, the inventors discovered that existing technologies lacked sufficient control over the injection position and height of the grout. To address this, this solution utilizes a height adjustment device on the grouting positioning frame to adjust the height of the grouting equipment and a horizontal adjustment device to adjust the position along the injection path. This allows for more flexible adjustment of the grouting position, meeting the testing requirements of different working conditions and ensuring stable grouting positions across different batches.

[0036] Furthermore, existing technologies can generally only read the distance of the slurry along the water flow direction or the residual slurry thickness at a single measuring point. However, the surface of the slurry after water erosion usually exhibits an irregular accumulation pattern, with phenomena such as local bulges, thinning at the edges, agglomeration, and water film coverage. Moreover, existing technologies rely on longitudinally set scales on the sidewalls of the test tank to observe its height, which is easily affected by tank wall refraction, parallax, slurry adhesion to the wall, and reading angle, resulting in only approximate readings near the tank wall and failing to obtain the residual slurry thickness at different lateral positions. To overcome these problems, this solution also includes a sliding support that can slide across the erosion test tank. The sliding support is horizontally mounted above the erosion test tank, with several downward-facing distance sensors mounted on its top. Simply moving the position of the sliding support moves each distance sensor, thereby measuring the thickness of the residual slurry along the flow path. In addition, several distance sensors are distributed along the span of the scour test tank, so the slurry thickness at multiple points along the width direction can be obtained. Compared with the existing technology, which can only measure at a single point and can only read the slurry thickness on the sidewall, this application can accurately obtain the thickness distribution curve of the residual slurry along the test tank and its distribution curve along the width direction, which is beneficial for analyzing the scour influence range and thickness attenuation law.

[0037] The test method based on the dynamic water erosion resistance test device for grouting materials according to this application includes the following steps:

[0038] S1. Prepare the grouting material to be tested;

[0039] S2. Start the water supply unit to allow water to flow through the flow stabilization unit into the flushing test tank; during this period, read the real-time flow rate through the flow meter and control the real-time water supply unit to ensure that the average flow velocity in the flushing test tank reaches the set requirements.

[0040] S3. Inject the set volume of the grouting material to be tested into the scour test tank using grouting equipment;

[0041] S4. Continuously flush the grouting material at the set flow rate for a set time, and observe and record the changes in the state of the grouting material during the flushing process;

[0042] S5. After flushing is completed, shut off the real-time water supply unit and drain the residual water in the flushing test tank; take the grouting position as the starting point and measure the thickness of the residual grouting material in the flushing test tank along the water flow direction to obtain the thickness distribution data along the process.

[0043] S6. Collect residual grouting material in sections, dry them in drying ovens until constant weight, and weigh the residual dry mass of grouting material in each section.

[0044] S7. Calculate the total retention rate of grouting material, the proportion of segmented mass, and the centroid of thickness distribution:

[0045] R=m r / m0×100%; where: R is the total retention rate; m r m0 represents the total residual dry mass; m0 represents the theoretical injected dry mass.

[0046] P i =m i / m r ×100%; Where: P i Let m be the segment quality of the i-th segment; i Let be the residual dry mass of the i-th segment;

[0047] x c =Σx j h j / Σh j In the formula: x c x is the axial distance between the centroid of the thickness distribution and the grouting location; j h is the axial distance between the j-th measuring point and the grouting position. j Let be the thickness of the residual grouting material at the j-th measuring point.

[0048] This method employs a benchmark solid content calibration and residual slurry drying and weighing approach, which reduces the impact of residual slurry moisture content variations on quality evaluation results, making the evaluation results closer to the slurry's true solid retention capacity. Furthermore, this application not only obtains the total residual slurry amount but also effectively evaluates the slurry's spatial stability. Through thickness measurement along the injection point and segmented dry mass collection, indicators such as total retention rate, segmented mass proportion, thickness distribution centroid, and influence range can be obtained. This experimental method can determine whether the slurry is concentrated near the injection point, rather than simply determining whether there is still residue.

[0049] Furthermore, the theoretical injected dry mass m0 is obtained by measuring the reference volume V from the grouting material to be tested prepared in step S1. s The slurry sample was placed in a container of known mass, dried to constant weight, and then weighed to obtain the dry mass m corresponding to the reference volume. s ; Calculate the theoretical injected dry mass m0: m0 = m s ×V0 / V s In the formula, V0 is the set volume in step S3.

[0050] Compared with the prior art, the present invention has at least the following advantages and beneficial effects:

[0051] 1. The present invention provides a dynamic water erosion resistance test device and test method for grouting materials. The device can accurately measure the water flow rate through a flow meter and use this as a basis to control the water supply of the water supply unit. This enables real-time monitoring and stable adjustment of the initial flow rate in the erosion test tank, reducing the impact of flow velocity fluctuations on the test results.

[0052] 2. The present invention provides a dynamic water erosion resistance test device and test method for grouting materials. The flow stabilization unit, through a coherent approach of "weakening pulsation, eliminating vortices, reducing turbulence, and smooth introduction," can reduce the impact of local disturbances at the inlet end of the erosion test tank on the grout deposition, stripping, and migration process. This makes the water flow more stable when entering the erosion test tank, allowing the test results to accurately reflect the erosion resistance performance of the grouting material itself, rather than the differences in the inlet flow field. This significantly reduces the interference of velocity fluctuations and flow field disturbances on the test results.

[0053] 3. This invention provides a dynamic water erosion resistance testing device and method for grouting materials, which can obtain the grout deposition situation in different areas along the downstream direction, and thus determine the deposition stability of the tested grouting material. By measuring the thickness of the residual grout along the injection point and collecting segmented dry mass, indicators such as total retention rate, segmented mass ratio, thickness distribution centroid, and influence range can be obtained. This method effectively determines whether the grouting material is concentrated near the injection point, which has significant technical advantages compared to existing technologies that only determine the amount of erosion.

[0054] 4. The present invention provides a dynamic water erosion resistance test device and test method for grouting materials, which overcomes the problems of inconvenient removal of the base plate and easy interference with adjacent base plates or misalignment of grout when forcibly removed, thus significantly improving the accuracy of subsequent analysis.

[0055] 5. This invention provides a dynamic water erosion resistance testing device and method for grouting materials, which allows for flexible adjustment of the grouting position to meet the testing requirements of different working conditions, while also facilitating the maintenance of stable grouting positions for different batches. It can accurately obtain the thickness distribution curve of residual grout along the friction path and its distribution curve along the width direction, which is beneficial for analyzing the erosion influence range and thickness attenuation law.

[0056] 6. The present invention provides a dynamic water erosion resistance test device and test method for grouting materials. It adopts the technical approach of benchmark solid content calibration and residual grout drying and weighing, which can reduce the impact of residual grout moisture content changes on quality evaluation results and make the evaluation results closer to the true solid phase retention capacity of the grout. Attached Figure Description

[0057] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0058] Figure 1 This is a schematic diagram of a device according to a specific embodiment of the present invention;

[0059] Figure 2 This is a schematic diagram of the internal structure of the current stabilizing unit in a specific embodiment of the present invention;

[0060] Figure 3 This is a schematic diagram of the cellular rectifier in a specific embodiment of the present invention;

[0061] Figure 4 This is a schematic diagram of the flow stabilizer plate in a specific embodiment of the present invention;

[0062] Figure 5 This is a schematic cross-sectional view of the scouring test tank in a specific embodiment of the present invention;

[0063] Figure 6 This is a schematic diagram of the base plate in a specific embodiment of the present invention;

[0064] Figure 7 This is a schematic diagram of the connection of the grouting pipe in a specific embodiment of the present invention.

[0065] The attached diagram shows the markings and corresponding component names:

[0066] 1-Water storage tank, 2-Water pump, 3-Flow stabilizing unit, 4-Flow meter, 5-Data recording and display module, 6-Grouting positioning frame, 7-Grouting equipment, 8-Support frame, 9-Scribble test tank, 10-Segment marking point, 11-Flow stabilizing plate, 12-Round hole, 13-Drain outlet, 14-Height adjustment device, 15-Horizontal adjustment device, 16-Connector, 17-Grouting pipe, 18-Sliding bracket, 19-Distance sensor, 20-Axial scale, 21-Rigid frame;

[0067] 301-Buffer flow stabilization zone, 302-Cellular rectifier, 303-Rectifier mesh group, 304-Gradual narrowing flow guide zone, 305-Shell, 306-Inlet end, 307-Outlet end, 308-Baffle arc-shaped component, 309-Polygonal channel;

[0068] 901 - Base plate, 902 - Placement plate. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for explaining the invention only and are not intended to limit the invention. In the description of this application, it should be understood that terms such as "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "high," "low," "inner," and "outer," indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application.

[0070] Example 1:

[0071] like Figures 1 to 4 The device shown is a dynamic water erosion resistance test device for grouting materials, including a water supply unit, a flow stabilizing unit 3, a flow meter 4, an erosion test tank 9 connected in sequence, a grouting device 7 for grouting into the erosion test tank 9, and a friction thickness measuring unit for measuring the thickness of the grout in the erosion test tank 9.

[0072] The water supply unit in this embodiment includes a water storage tank 1, a water pump 2 for drawing water from the water storage tank 1, and a filter device located at the water inlet of the water pump 2. The output end of the water pump 2 is connected to the inlet end 306.

[0073] Preferably, the water supply unit also includes a self-circulating pipeline, which can self-circulate under normal conditions; the water storage tank 1 can also be equipped with a drain valve to facilitate emptying after the test results are obtained.

[0074] The current stabilizing unit in this embodiment is as follows: Figure 2 As shown, it includes a housing 305, an inlet end 306 and an outlet end 307 located on opposite sides of the housing 305, and a buffer flow stabilization zone 301, a honeycomb rectifier 302, a rectifier network 303 and a gradually narrowing flow guiding zone 304 arranged sequentially along the direction from the inlet end 306 to the outlet end 307; the inlet end 306 is connected to the water supply unit, and the outlet end 307 is connected to the flow meter 4.

[0075] In this embodiment, the width of the buffer flow stabilization zone 301 is 1.2 to 2.5 times the width of the scouring test tank 9, and the height of the buffer flow stabilization zone 301 is 1.2 to 3.0 times the height of the scouring test tank 9; a flow-blocking arc-shaped component 308 is provided in the buffer flow stabilization zone 301, and the concave surface of the flow-blocking arc-shaped component 308 faces the inlet end 306.

[0076] Preferably, the length of the buffer flow stabilization zone 301 along the water flow direction is 80–300 mm.

[0077] Preferably, the flow-blocking arc-shaped component 308 is an arc surface or a spherical surface; it is as follows: Figure 2 The central angle corresponding to the longitudinal section shown is greater than 120°.

[0078] In this embodiment, the cellular rectifier 302 has an aperture ratio of 70% to 95% and includes several polygonal channels 309. The axis of each polygonal channel 309 is parallel to the line connecting the inlet end 306 to the outlet end 307. The hydraulic diameter of each polygonal channel 309 is 3 to 10 mm, and the length of each polygonal channel 309 is 5 to 12 times its hydraulic diameter. In this embodiment, the polygonal channel 309 is hexagonal or rectangular.

[0079] In this embodiment, the rectifier mesh group 303 includes 2 to 5 layers of rectifier mesh distributed sequentially, and the opening ratio of the rectifier mesh is 40% to 80%; the mesh count of each rectifier mesh gradually increases in the direction of the line connecting the inlet end 306 to the outlet end 307.

[0080] Preferably, the rectifier mesh group 303 consists of three layers of rectifier mesh: a coarse mesh, a medium mesh, and a fine mesh. The coarse mesh has 10–20 mesh, the medium mesh has 30–50 mesh, and the fine mesh has 60–100 mesh; the spacing between adjacent rectifier meshes is 10–50 mm. Each layer of rectifier mesh can be made of stainless steel mesh, nylon mesh, or water-resistant polymer.

[0081] In this embodiment, the inlet cross-section of the tapered guide zone 304 matches the outlet cross-section of the rectifier mesh group 303, and the outlet cross-section of the tapered guide zone 304 matches the outlet end 307. Preferably, the length of the tapered guide zone 304 along the water flow direction is 100–400 mm, the tapering half-angle is 5°–15°, preferably 7°–10°; the inner wall of the tapering zone is preferably a smooth curved surface or a rounded transition structure.

[0082] In this embodiment, the scouring test tank 9 includes an inlet and a drain outlet 13 axially away from the inlet; it also includes a flow stabilizer 11 detachably installed inside the scouring test tank 9. The flow stabilizer 11 is located between the inlet and the grouting device 7, and the distance between the flow stabilizer 11 and the grouting device 7 is 150~600mm, preferably 200~300mm; the thickness of the flow stabilizer 11 is 1~5mm, preferably 2~3mm; and it has several circular holes 12 with a diameter of 2~6mm, and the opening rate is 35%~70%.

[0083] In this embodiment, the scouring test tank 9 is made of transparent acrylic, plexiglass, or other transparent water-resistant materials. Preferably, the tank is a U-shaped transparent water tank with a length of 1.5–3.0 m and a height of 8–20 cm; more preferably, the tank is approximately 2.0 m long and approximately 10 cm high. The transparent sidewalls of the tank facilitate observation of the diffusion, peeling, agglomeration, deposition, and migration processes of the slurry under the action of flowing water.

[0084] Preferably, the device further includes a data recording and display module 5, used to acquire and display the monitoring data from the flow meter 4 in real time. The average flow velocity in the tank can be calculated based on the flow rate and the cross-sectional area of ​​the scouring test tank 9.

[0085] Adjust the speed of pump 2 according to the target flow velocity to stabilize the flow velocity in the scouring test tank 9 within the set range. The test flow velocity can be set to 0.1~1.0m / s according to the engineering hydraulic conditions, preferably set to three levels: 0.2m / s, 0.3m / s and 0.4m / s, to simulate different dynamic water scouring intensities.

[0086] Example 2:

[0087] A dynamic water erosion resistance testing device for grouting materials, based on Example 1, such as... Figures 1 to 6 As shown, in this embodiment, the position directly opposite the grouting equipment 7 is taken as the axial zero point, and the interior of the scour test tank 9 located downstream of the grouting equipment 7 is divided into several sequentially adjacent test sections. In this embodiment, the test sections are divided into four sections: 0-20cm, 20-60cm, 60-100cm, and 100-140cm. After the scour is completed, the residual grout in each test section is collected, dried to constant weight, and then weighed to obtain the residual dry mass of each section and the total residual dry mass.

[0088] Preferably, several segment markers 10 are provided on the side wall of the scour test tank 9 to mark the boundaries between adjacent segments.

[0089] Preferred, such as Figure 6 As shown, the test section includes a base plate 901 with a convex cross-section and a spacer plate 902 detachably connected to the inner wall of the scour test tank 9 and matching the lateral notches on both sides of the base plate 901. In this embodiment, the spacer plate 902 is made of transparent acrylic material and is detachably connected to the side wall of the scour test tank 9 by bolts or magnetic attraction.

[0090] More preferably, a layer of sealing material can be applied to the stepped surfaces on both sides of the base plate 901; when the bottom end of the occupant plate 902 is located on the stepped surface, the sealing material is squeezed to ensure a sealing effect. The sealing material can be a rubber layer.

[0091] In this embodiment, the grouting equipment 7 is installed on the grouting positioning frame 6, and the grouting positioning frame 6 is fixed on the scour test tank 9. The grouting positioning frame 6 is equipped with a height adjustment device 14 for adjusting the height of the grouting equipment 7 and a horizontal adjustment device 15 for adjusting the position of the grouting equipment 7 along the axial direction of the scour test tank 9; the output end of the grouting equipment 7 faces downward and is connected to the connector 16 and the grouting pipe 17 in sequence.

[0092] The thickness measurement unit includes a sliding bracket 18 slidably mounted on the scour test tank 9 along the axial direction, and a plurality of distance sensors 19 evenly installed on the sliding bracket 18, with the measuring direction of the distance sensors 19 facing downwards; it also includes an axial scale 20 set along the bottom or wall of the scour test tank 9. The distance sensors 19 may be laser rangefinders.

[0093] In a more preferred embodiment, such as Figure 7 As shown, the hollow connector 16 is rotatably connected to the bottom of the output end of the grouting equipment 7. The grouting pipe 17, which is made of metal corrugated pipe, is fixedly connected below the connector 16. A rigid frame 21 is fitted over the metal corrugated pipe and is also fixed to the bottom of the connector 16. The bottom end of the rigid frame 21 has a bend. This scheme allows for adjustment of the angle between the injected grout and the water flow direction by rotating the connector 16, thereby simulating the grouting reinforcement operation environment under different formation water flow conditions. The metal corrugated pipe is confined inside the rigid frame 21 and therefore cannot deform freely. It can only adjust the grouting angle by following the rigid frame 21. In addition, the rotation angle of the connector 16 is controlled by manual force. After rotation, the friction between the connector 16 and the output end of the grouting equipment 7 achieves temporary positioning. Since the water flow velocity in this application is a simulation of formation water, the flow velocity will not be too fast. Therefore, it can be achieved by selecting a contact surface with high frictional resistance. Of course, other temporary positioning structures can be added as needed during actual use, such as using pins, magnetic attraction, buckles, etc. to achieve temporary positioning of the rotation angle of the connector 16, which is not difficult for those skilled in the art to implement.

[0094] Example 3:

[0095] A method for testing the dynamic water erosion resistance of grouting materials, based on the test apparatus in Example 1 or 2, includes the following steps:

[0096] S1. Prepare and stir the grouting material to be tested until it is uniform.

[0097] Measure the reference volume V from the grouting material to be tested. s The slurry sample was placed in a container of known mass, dried to constant weight, and then weighed to obtain the dry mass m corresponding to the reference volume. s ;

[0098] Theoretical calculation of injected dry mass m0: m0 = m s ×V0 / V s In the formula, V0 is the set volume in step S3.

[0099] S2. Start the water supply unit to allow water to flow through the flow stabilization unit 3 into the flushing test tank 9; during this period, read the real-time flow rate through the flow meter 4 and control the real-time water supply unit to ensure that the average flow velocity in the flushing test tank 9 reaches the set requirements.

[0100] S3. Adjust the height and lateral position and / or grouting angle of the grouting equipment 7, and inject the set volume of the grouting material to be tested into the scour test tank 9 through the grouting equipment 7.

[0101] S4. Continuously flush the grouting material at a set flow rate for a set time, observe and record the changes in the state of the grouting material during the flushing process, such as grout peeling, agglomeration, deposition, diffusion and migration.

[0102] S5. After flushing is completed, shut off the real-time water supply unit and drain the residual water in the flushing test tank 9; take the grouting position as the starting point and measure the thickness of the residual grouting material in the flushing test tank 9 along the water flow direction to obtain the thickness distribution data along the process.

[0103] Specifically, in this embodiment, the sliding bracket 18 is slid downstream at a set speed from the axial zero point, during which distance sensors 19 are activated to perform measurements at equal intervals; the distance between measuring points can be set to 2-10 cm. The thickness variation curve of the deposited slurry along the path can be obtained by subtracting the measured distance from the theoretical distance when no slurry is deposited.

[0104] S6. Collect the residual grouting material in sections, dry them in drying ovens until constant weight, and weigh the residual dry mass of the grouting material in each section.

[0105] Specifically, in this embodiment, residual grouting material can be collected in segments using the following method:

[0106] Remove the corresponding occupant plate 902 for each measuring section. Workers use their hands or tools to reach into the steps on both sides of each base plate 901 and lift each base plate 901 upwards smoothly.

[0107] Use a scraping tool to scrape the residual slurry on each base plate 901 into the sample container.

[0108] S7. Calculate the total retention rate of grouting material, the proportion of segmented mass, and the centroid of thickness distribution:

[0109] R=m r / m0×100%; where: R is the total retention rate; m r m0 represents the total residual dry mass; m0 represents the theoretical injected dry mass.

[0110] P i =m i / m r ×100%; Where: P i Let m be the segment quality of the i-th segment; i Let be the residual dry mass of the i-th segment;

[0111] x c =Σx j h j / Σh j In the formula: x c x is the axial distance between the centroid of the thickness distribution and the grouting location; j h is the axial distance between the j-th measuring point and the grouting position. j Let be the thickness of the residual grouting material at the j-th measuring point.

[0112] In step S7, if the thickness measurement unit along the friction path also sets up multiple measuring points laterally along the scouring test groove at each axial measuring point, then the lateral coordinates and axial coordinates of the centroid of the thickness distribution of the residual grouting material are calculated respectively.

[0113] When all axial and transverse measuring points are arranged at equal intervals, the formula for calculating the transverse coordinate of the centroid of the thickness distribution is:

[0114] ;

[0115] In the formula: y c y is the lateral coordinate of the centroid of the thickness distribution; k h is the lateral distance between the k-th lateral measuring point and the preset lateral baseline; jk denoted as , where is the thickness of the residual grouting material at the j-th axial measuring point and the k-th lateral measuring point; n is the number of axial measuring points; and m is the number of lateral measuring points.

[0116] The preset transverse baseline can be the transverse center line of the scouring test tank or one side wall of the scouring test tank.

[0117] Accordingly, the formula for calculating the axial coordinate of the centroid of the thickness distribution in this state is:

[0118] ;

[0119] In the formula: x c This represents the axial distance between the centroid of the thickness distribution and the grouting location.

[0120] Through x c and y c They can jointly characterize the two-dimensional spatial deposition distribution characteristics of residual grouting material in the scour test tank, where x cUsed to reflect the degree of migration of the slurry along the direction of water flow, y c It is used to reflect the degree of displacement of the slurry in the direction perpendicular to the water flow or the uniformity of lateral deposition.

[0121] When the axial or lateral spacing of measuring points is unequal, the centroid of the thickness distribution can be calculated by weighting the range represented by each measuring point:

[0122] ;

[0123] ;

[0124] In the formula: Δx j Δy represents the axial spacing corresponding to the j-th axial measuring point. k This represents the horizontal spacing corresponding to the k-th horizontal measuring point. The range represented by each measuring point can be adaptively set according to the specific working conditions.

[0125] To verify the validity of this application, dynamic water erosion resistance tests were conducted on nine groups of grouting material mixes using this application. The tests were conducted at three constant flow velocities of 0.2 m / s, 0.3 m / s, and 0.4 m / s. Each group of grout was subjected to erosion tests at different flow velocities for 3 minutes.

[0126] Before the experiment, a 20 mL sample of slurry was taken when the slurry was in a uniformly dispersed state. After drying to constant weight, the sample was weighed to obtain the baseline dry mass of that volume of slurry. During the formal experiment, 40 mL of slurry was injected into the scouring test tank using a grouting device, allowing the slurry to undergo scouring, stripping, migration, and deposition under a constant flow rate. After scouring, the thickness of the residual slurry was measured along the water flow direction, and residual slurry was collected in four sections: 0–20 cm, 20–60 cm, 60–100 cm, and 100–140 cm. The residual slurry in each section was dried to constant weight and weighed to calculate the total retention rate, the percentage of mass in each section, the centroid of thickness distribution, and the range of influence.

[0127] The experimental results are shown in the table below:

[0128] The experimental results show that as the flow velocity increased from 0.2 m / s to 0.4 m / s, the average retention rate of the nine slurry groups decreased from 88.19% to 73.12%, indicating that increased flow velocity significantly weakens the slurry's ability to retain the solid phase. Simultaneously, the average thickness centroid shifted from 39.54 cm to 53.59 cm, and the average influence range expanded from 80.00 cm to 98.89 cm, suggesting that higher flow velocities promote the downstream migration and diffusion of the slurry from near-source deposition.

[0129] Different slurry mixes also exhibited significant differences at the same flow rate. Some slurries, while having a high total retention rate, showed a marked shift in deposition location; others were able to concentrate near the injection point, with a shorter migration distance, demonstrating better near-source plugging stability. Through a comprehensive evaluation of total retention rate, segmented mass ratio, thickness distribution centroid, and influence range, the slurry's scour resistance can be categorized into near-source stable accumulation type, downstream migration and dispersion type, and weakly stable and easily dispersed type.

[0130] Verification results show that this invention can effectively distinguish the dynamic water erosion resistance of grouting materials under different flow rates and mix proportions. Compared with methods that only use residual total mass or static anti-dispersion tests, this invention can simultaneously reflect the mass retention capacity and spatial migration characteristics of the grout, making it more suitable for the screening, evaluation, and optimization of grouting materials in water-rich fissure dynamic water sealing projects.

[0131] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0132] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Additionally, the term "connection" as used herein, unless otherwise specified, can refer to a direct connection or an indirect connection via other components.

Claims

1. A dynamic water erosion resistance testing device for grouting materials, characterized in that, It includes a water supply unit, a flow stabilizing unit (3), a flow meter (4), a scour test tank (9) connected in sequence, a grouting device (7) for grouting into the scour test tank (9), and a friction thickness measuring unit for measuring the thickness of the grout in the scour test tank (9). The flow stabilizing unit includes a housing (305), an inlet end (306) and an outlet end (307) located on opposite sides of the housing (305), and a buffer flow stabilizing zone (301), a honeycomb rectifier (302), a rectifier network (303) and a gradually narrowing guide zone (304) arranged sequentially along the direction from the inlet end (306) to the outlet end (307); the inlet end (306) is connected to the water supply unit, and the outlet end (307) is connected to the flow meter (4).

2. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The water supply unit includes a water storage tank (1), a water pump (2) for drawing water from the water storage tank (1), and a filter device located at the water inlet of the water pump (2). The output end of the water pump (2) is connected to the inlet end (306).

3. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The width of the buffer flow stabilization zone (301) is 1.2 to 2.5 times the width of the scouring test tank (9), and the height of the buffer flow stabilization zone (301) is 1.2 to 3.0 times the height of the scouring test tank (9); a flow-blocking arc-shaped component (308) is provided in the buffer flow stabilization zone (301), and the concave surface of the flow-blocking arc-shaped component (308) faces the inlet end (306).

4. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The cellular rectifier (302) has an opening ratio of 70% to 95% and includes several polygonal channels (309); the axis of the polygonal channel (309) is parallel to the line connecting the inlet end (306) to the outlet end (307); the hydraulic diameter of the polygonal channel (309) is 3 to 10 mm; and the length of the polygonal channel (309) is 5 to 12 times the hydraulic diameter of the polygonal channel (309).

5. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The rectifier mesh group (303) includes 2 to 5 layers of rectifier mesh distributed sequentially, and the opening ratio of the rectifier mesh is 40% to 80%; the mesh count of each rectifier mesh gradually increases from the inlet end (306) to the outlet end (307) in the line direction.

6. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The scouring test tank (9) includes an inlet and a drain outlet (13) axially away from the inlet; it also includes a flow stabilizer (11) detachably installed inside the scouring test tank (9), the flow stabilizer (11) being located between the inlet and the grouting device (7), and the distance between the flow stabilizer (11) and the grouting device (7) being 150~600mm; the thickness of the flow stabilizer (11) is 1~5mm, and several round holes (12) with a diameter of 2~6mm are opened on it, and the opening rate is 35%~70%.

7. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The scour test tank (9) located downstream of the grouting equipment (7) is divided into several adjacent test sections; the test section includes a bottom plate (901) with a convex cross-section and a detachable plate (902) that is connected to the inner wall of the scour test tank (9) and matches the lateral notches on both sides of the bottom plate (901).

8. The dynamic water erosion resistance test device for grouting materials according to claim 1, characterized in that, The grouting equipment (7) is installed on the grouting positioning frame (6). The grouting positioning frame (6) is equipped with a height adjustment device (14) for adjusting the height of the grouting equipment (7) and a horizontal adjustment device (15) for adjusting the position of the grouting equipment (7) along the axial direction of the scouring test trench (9). The output end of the grouting equipment (7) faces downward and is connected to the connector (16) and the grouting pipe (17) in sequence. The thickness measurement unit includes a sliding bracket (18) slidably mounted on the scouring test tank (9) along the axial direction, and a number of distance sensors (19) evenly mounted on the sliding bracket (18), with the measuring direction of the distance sensors (19) facing downward; it also includes an axial scale (20) set along the axial direction at the bottom or wall of the scouring test tank (9).

9. A test method for a dynamic water erosion resistance test device for grouting materials according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Prepare the grouting material to be tested; S2. Start the water supply unit so that the water flows through the flow stabilizing unit (3) into the flushing test tank (9); during this period, read the real-time flow rate through the flow meter (4) and control the real-time water supply unit so that the average flow rate in the flushing test tank (9) reaches the set requirements. S3. The grouting material to be tested, with a set volume, is injected into the scour test tank (9) through the grouting equipment (7); S4. Continuously flush the grouting material at the set flow rate for a set time, and observe and record the changes in the state of the grouting material during the flushing process; S5. After flushing is completed, shut off the real-time water supply unit and drain the residual water in the flushing test tank (9); take the grouting position as the starting point and measure the thickness of the residual grouting material in the flushing test tank (9) along the water flow direction to obtain the thickness distribution data along the process. S6. Collect residual grouting material in sections, dry them in drying ovens until constant weight, and weigh the residual dry mass of grouting material in each section. S7. Calculate the total retention rate of grouting material, the proportion of segmented mass, and the centroid of thickness distribution: R=m r / m0×100%; where: R is the total retention rate; m r Total residual dry mass; m0 represents the theoretically injected dry mass; P i =m i / m r ×100%; Where: P i Let m be the segment quality of the i-th segment; i Let be the residual dry mass of the i-th segment; x c =Σx j h j / Σh j In the formula: x c x is the axial distance between the centroid of the thickness distribution and the grouting location; j h is the axial distance between the j-th measuring point and the grouting location; j Let be the thickness of the residual grouting material at the j-th measuring point.

10. The test method according to claim 9, characterized in that, The theoretical dry mass m0 of the injection is obtained by measuring the reference volume V from the grouting material to be tested prepared in step S1. s A slurry sample was placed in a container of known mass, dried to constant weight, and then weighed to obtain the dry mass m corresponding to the reference volume. s ; Theoretical calculation of injected dry mass m0: m0 = m s ×V0 / V s In the formula, V0 is the set volume in step S3.

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