Migration loss test device and method for filling particles in karst pipeline

Abstract

The invention provides a karst pipeline internal filling particle migration loss test device and method, a glass tube is filled with a karst pipeline transparent similar material, a pressurization module is arranged at one end of the glass tube, a colored solution is arranged between the pressurization module and the karst pipeline filling material, and a plugging module is arranged at the other end of the glass tube. Permeation seams are formed in the middles of the plugging modules. Through pressurization of the pressurization module, the colored solution flows through the karst pipeline filling material, carries the filling particles to penetrate through the seepage seam to enter the seepage fluid collecting pipe, and finally converges into the flow metering module. In the test process, a laser is adopted to irradiate the karst pipeline filling material to form a laser section, and digital photographing measurement analysis is carried out to obtain the permeation path change of the colored solution and the movement change rule of particles in the filling material; analyzing the permeability coefficient and porosity of the karst pipeline filling structure according to the water body quality and particle quality of the percolating fluid; therefore, the particle migration and loss rule of the filling in the karst pipeline is researched.

Description

Technical Field

[0001] The invention belongs to the technical field of karst pipelines, and in particular relates to a device and method for testing the migration and loss of filling particles inside a karst pipeline. Background Art

[0002] In underground projects such as karst tunnel projects, understanding the migration and loss of filling particles inside karst pipes helps engineers formulate reasonable construction plans and safety measures. Affected by engineering geological and hydrological conditions, the filling particle structure inside karst pipes is often very complex, which leads to a variety of inconsistent movement deformation and damage characteristics due to seepage erosion after being exposed during tunnel excavation, inducing different types of water and mud inrush disasters. Therefore, in the process of geological exploration and engineering design of karst tunnels, it is necessary to consider the migration and loss laws of filling particles inside karst pipes to formulate reasonable construction plans and preventive control measures.

[0003] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art. The present invention provides a device and method for testing the migration and loss of filling particles inside a karst pipeline.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A karst pipeline internal filling particle migration and loss test device, the test device comprising:

[0007] A glass tube, wherein the glass tube is an L-shaped transparent tube body with two open ends, and the interior of the glass tube is filled with a transparent material similar to the filling of a karst pipeline, which is used to simulate the filling structure material of the karst pipeline;

[0008] A pressurizing module, wherein the pressurizing module is arranged at one end of the glass tube, a colored solution is arranged between the pressurizing module and the karst pipeline filling material, and the hydraulic coupling effect of the karst pipeline is simulated by pressurizing the colored solution;

[0009] A plugging module, the plugging module is arranged at the other end of the glass tube, a permeation seam is arranged in the middle of the plugging module, and the permeation seam is connected to the flow metering module through a permeate collecting pipe;

[0010] A laser irradiation module, which is arranged on the opposite side of the glass tube and the plugging module. The laser irradiation module is a movable red planar laser. The laser irradiates the karst pipe in the glass tube and fills the transparent similar material to form a laser section. An image acquisition device is used in front of the glass tube to continuously collect the laser section image.

[0011] The pressurizing module is used to apply pressure so that the colored solution seeps from the karst filling material to the flow metering module, and the permeability coefficient and porosity of the karst pipeline filling structure are analyzed by the water quality and particle quality of the seepage liquid; by continuously collecting and digitally photographing and measuring the laser section images of the karst pipeline filling material during the test, the changes in the permeation path of the colored solution and the movement changes of the particles inside the karst pipeline filling material are obtained.

[0012] Preferably, the inner wall of the glass tube is configured as an irregular concave-convex surface, and the karst filling material comprises fused quartz sand, amorphous silicon powder, liquid paraffin and n-tridecane.

[0013] Preferably, the glass tube is arranged on one side of a fixed steel frame, a bottom support for fixing the test bench is provided at the bottom of the fixed steel frame, and a diagonal support connected to the bottom support is provided on the side of the glass tube away from the fixed steel frame.

[0014] Preferably, the diagonal brace and the middle part of the fixed steel frame are provided with a strip hole facing the glass tube, the longitudinal length of the strip hole is adapted to the height of the karst filling material, the laser emitted by the planar laser passes through the strip hole and irradiates the transparent similar material filled in the karst pipe to form a laser section, and the image acquisition device is used to continuously collect the laser section image.

[0015] Preferably, the pressurizing module comprises:

[0016] A main frame, wherein a first pressure rod pointing to the glass tube is provided in the middle of the main frame, and a first piston plate is provided at one end of the first pressure rod extending into the glass tube;

[0017] A pressure tube, one end of which is connected to a pressure pump, and the other end of which passes through the first piston plate and points to the karst pipeline filling material, so as to pump a high-pressure colored solution between the first piston plate and the karst pipeline filling material.

[0018] Preferably, the blocking module comprises:

[0019] a second piston plate, the second piston plate being slidably mounted on the glass tube to contact the karst pipeline filling material, and a permeable seam being provided in the middle of the second piston plate;

[0020] A second pressure rod, the second pressure rod being supported on the corners of the second piston plate via a plurality of claws;

[0021] A slide plate, wherein the second piston plate is close to a slide groove on one side of the karst pipeline filling material, the slide groove is located on one side of the permeable seam, and the depth of the slide groove is matched with the thickness of the slide plate, so that the second piston plate has a flat surface facing the karst pipeline filling material; the width of the permeable seam can be adjusted by sliding the slide plate;

[0022] The edge of the slide plate is provided with a folded portion corresponding to the permeable seam, and the side of the second piston plate away from the karst pipeline filling material is provided with a limiting strip corresponding to blocking the folded portion.

[0023] Preferably, the flow metering module comprises a permeate collection pipe, a metering tank, a filter screen and an electronic scale, wherein the filter screen is arranged above the metering tank to filter out particles in the permeate.

[0024] Preferably, the test device further comprises an image acquisition device and a pressure acquisition device correspondingly connected to the controller;

[0025] The image acquisition instrument is facing the glass tube to continuously acquire the laser section image of the karst pipe filling material inside the glass tube; the pressure acquisition instrument is correspondingly connected to the pressurizing module and the plugging module to acquire the rated pressure data of the pressurizing module and the plugging module.

[0026] A method for testing the migration and loss of filling particles inside a karst pipeline, wherein the test is carried out by any of the test devices, and the water quality and particle quality of the seepage fluid are obtained through the test device, so as to analyze the permeability coefficient and porosity of the karst pipeline filling structure; and the changes in the permeation path of the colored solution and the movement change rules of the particles inside the filling material are obtained by continuously collecting and digitally photographing the laser section images of the karst pipeline filling material during the test.

[0027] Preferably, the method comprises the following steps:

[0028] Step S1, sealing the bottom of the glass tube with a temporary cover plate;

[0029] Step S2, preparing a transparent similar material for filling the karst pipeline, and mixing the multi-walled carbon nanotubes into the karst pipeline filling material and filling it into the glass tube in multiple times, each filling height is 40 mm, and after filling, the glass tube is placed in a vacuum box for 15 minutes of vacuum treatment until the filling height reaches 360 mm;

[0030] Step S3, fixing the glass tube on the test bench through a fixed steel frame, and installing the plugging module and the pressurizing module;

[0031] Step S4, sliding the blocking module slide plate to close the seepage seam; turning off the colored solution pressure pump, so that the pressure module piston plate is closely attached to the karst pipeline filled with transparent similar materials; applying rated pressure to the pressure module piston plate, so that the transparent similar materials filled in the pipeline are statically consolidated for a rated time under the rated consolidation pressure;

[0032] Step S5, after the consolidation is completed, the planar laser is turned on to irradiate the karst pipeline in the glass tube after being filled with transparent similar materials to form a laser section, and the image acquisition device is used to continuously collect the laser section image in front of the glass tube, and the collected images are digitally photographed, measured and analyzed to obtain the changes in the permeation path of the colored solution and the movement change rules of the particles inside the karst pipeline filling material;

[0033] Step S6, adjusting the width of the seepage seam to a predetermined value by sliding the slide plate of the plugging module, turning on the pressurizing module and the colored solution pressurizing pump, allowing the colored solution to seep from the top of the karst pipeline filling material to the flow metering module, allowing the seepage liquid to be filtered through the filter screen and then discharged to the metering tank, and analyzing the permeability coefficient and porosity of the karst pipeline filling structure by the water quality and particle quality of the seepage liquid;

[0034] Step S7, stop the test, turn off the instrument, clean and store the instrument.

[0035] Beneficial effects: By filling the karst pipeline with transparent similar materials to simulate the karst pipeline filling structure, the pressurized module is used to make the colored solution flow through the karst pipeline filling material, carry the filling particles through the permeable seam and enter the seepage fluid collection pipe, and finally merge into the flow metering module. During the experiment, the karst pipeline filling material was irradiated with laser to form a laser section and digital photography measurement and analysis were performed to obtain the changes in the permeation path of the colored solution and the movement of the particles inside the filling material; the permeability coefficient and porosity of the karst pipeline filling structure were analyzed by the water quality and particle quality of the seepage fluid; thus, the particle migration and loss law of the filling material inside the karst pipeline was studied. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0037] Figure 1 It is a structural schematic diagram of an experimental device in a specific embodiment provided by the present invention;

[0038] Figure 2 This is a schematic diagram of the assembly of a glass tube in a specific embodiment provided by the present invention;

[0039] Figure 3 It is a schematic diagram of the assembly of the slide plate and the second piston plate in a specific embodiment provided by the present invention;

[0040] Figure 4 A schematic structural diagram of a slide plate in a specific embodiment provided by the present invention;

[0041] Figure 5 This is a simplified side view of a fixed steel frame in a specific embodiment provided by the present invention.

[0042] In the figure: 1. digital camera; 2. pressurized tube; 3. glass tube; 4. karst pipeline filled with transparent similar materials; 5. metering tank; 6. filter screen; 7. image acquisition instrument and pressure acquisition instrument; 8. fixed steel frame; 9. main frame; 10. first pressurized rod; 11. first piston plate; 12. controller; 13. injection pressurizer; 14. water pump; 15. oil pump; 16. strip hole; 17. diagonal support; 18. second pressurized rod; 19. second piston plate; 20. limit strip; 21. slide plate; 22. folding part; 23. penetration seam; 24. planar laser; 25. electronic scale; 26. test bench; 27. seepage liquid collection pipe. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0044] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0045] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0046] like Figure 1-5As shown, in order to study the migration and loss law of particles inside the karst pipeline filling structure and the deformation and failure characteristics under the action of hydraulic coupling, the present application provides a karst pipeline internal filling particle migration and loss test device, the test device includes a glass tube 3, a pressurization module, a plugging module and a laser irradiation module, the glass tube 3 is a transparent tube body with open ends, the glass tube 3 is preferably organic glass, and the glass tube 3 is a square tube formed by gluing multiple organic glass plates, and the inside of the glass tube 3 is filled with a transparent material 4 similar to the karst pipeline filling, fused quartz sand is used to simulate the gravel and sand particles in the karst pipeline filling, and amorphous silicon powder is used to simulate The clay particles in the karst pipeline filling material are prepared by mixing liquid paraffin and n-tridecane in a mass ratio of 1:0.85 to simulate the karst pipeline filling structure pore water, so as to simulate the filling structure material of the karst channel; the pressurizing module is arranged at one end of the glass tube 3, and a colored solution is arranged between the pressurizing module and the karst pipeline filling transparent similar material 4 to simulate the internal pore water in the karst pipeline filling material, and the colored solution can be a mineral oil solution with 1% light blue dye, and the colored solution is pressurized to make it penetrate through the karst pipeline filling transparent similar material 4 to simulate the hydraulic coupling effect of the karst pipeline.

[0047] The plugging module is arranged at the other end of the glass tube 3, and a seepage seam 23 is arranged in the middle of the plugging module, so as to discharge the seepage liquid passing through the transparent similar material 4 filled in the karst pipeline. The seepage seam 23 is connected to the flow metering module through the seepage liquid collecting tube 27. The water body and particles in the seepage liquid are separated by the flow metering module. In response to the pressurization through the pressurizing module, the colored solution seeps from the karst pipeline filling material 4 to the flow metering module. The permeability coefficient and porosity of the karst pipeline filling structure are analyzed by the water quality and particle quality of the seepage liquid, so as to study and observe the migration and loss law of the filling particles inside the karst pipeline.

[0048] In this embodiment, the colored solution is prepared by mixing liquid paraffin and n-tridecane in a mass ratio of 1:0.85 and adding 1% of a light blue dye. The refractive indexes of the fused quartz sand, amorphous silicon powder and the colored solution are substantially the same, thereby avoiding errors caused by image acquisition.

[0049] In an optional embodiment, the glass tube 3 is L-shaped, with an outer length of 250 mm, a height of 450 mm, a thickness of 150 mm, an irregular concave-convex inner surface, an inner space cross-sectional size of about 100 mm, and a square glass tube 3 and an outer steel frame fixing device, which is used to simulate the actual irregular inner surface of the curved karst pipeline. The karst pipeline is filled with transparent similar materials 4 including molten quartz sand, amorphous silicon powder, liquid paraffin and n-tridecane, and the mass ratio of the four is 1:5:5:4.25.

[0050] Fused quartz sand is used to simulate gravel and sand particles in karst pipeline fillings, amorphous silicon powder is used to simulate clay particles in karst pipeline fillings, and mineral oil solution (mixed by liquid paraffin and n-tridecane at a mass ratio of 1:0.85) is used to simulate the internal pore water in karst pipeline fillings. When the glass tube 3 is filled with transparent similar materials of karst tunnel filling structure, it can be combined with a digital photography measurement system to realize the observation and analysis of the internal particle migration law and deformation and failure characteristics of the karst pipeline filling structure.

[0051] Specifically, the mass and particle size range of fused quartz sand and amorphous silicon powder are determined according to the composition and particle grading curve of the actual karst pipeline filling structure medium, mixed with mineral oil solution and vacuum treated to prepare a transparent similar material for karst pipeline filling.

[0052] In an optional embodiment, the glass tube 3 is arranged on one side of a fixed steel frame 8. The fixed steel frame 8 is used to ensure the safety and stability of the L-shaped glass tube 3 under the test loading state. It is fixed to the steel plate of the test bench 26 by a "diagonal brace" method. Specifically, a bottom support for fixing the test bench 26 is provided at the bottom of the fixed steel frame 8, and a diagonal brace 17 connected to the bottom support is provided on the side of the glass tube 3 away from the fixed steel frame 8. Both ends of the diagonal brace 17 are fixed to the bottom support and the fixed steel frame 8 by bolts.

[0053] The test bench 26 is composed of 26 steel plates and a bottom support frame. The 26 steel plates of the test bench are 1200 mm in length and 500 mm in width, and are mainly used to provide a test operation platform for the pressurization module and the plugging module.

[0054] In addition, a water hole is reserved at the position of the test bench 26 corresponding to the penetration seam 23 of the plugging module, so as to facilitate the water and particles flowing out of the seepage liquid collection pipe 27 to be introduced into the flow metering module below through the loss collection port.

[0055] Specifically, a guide plate or a guide groove is provided at the lower end of the glass tube 3 or at the outlet of the seepage seam 23 of the blocking module, so as to collect the permeate and guide it to the flow metering module through the permeate collecting pipe 27 below.

[0056] In this embodiment, the height of the bottom support frame is 600 mm, the main purpose of which is to ensure the stability of the visualization seepage test system of the deep-buried karst tunnel filling structure and to provide a height space to facilitate the test operation.

[0057] In an optional embodiment, a strip hole 16 facing the glass tube 3 is provided in the middle of the diagonal support 17 and the fixed steel frame 8, and the longitudinal length of the strip hole 16 is adapted to the height of the karst pipe filling material 4, ensuring that the surface laser emitted by the laser 24 can penetrate the entire glass tube 3. The laser emitted by the laser 24 passes through the strip hole 16 and then irradiates the transparent similar material 4 filled in the karst pipe to form a laser section.

[0058] The test device also includes an image acquisition instrument and a pressure acquisition instrument 7 corresponding to the controller 12. The image acquisition instrument is a digital camera 1, which is facing the glass tube 3 to acquire images of the karst pipe filling material 4 inside the glass tube 3. The laser 24 completes the internal plane laser spotting of the transparent similar material of the karst pipe filling structure by emitting laser. The digital camera 1 is connected to the computer to realize the timing and fixed-point acquisition of the laser spotting image. The controller 12 can be a PC terminal, pre-installed with a software system for data processing, and the software system analyzes the collected test images for seepage path, particle migration, deformation and failure characteristics of the filling body, etc.

[0059] Furthermore, the pressure collector is connected to the pressurizing module and the plugging module to collect the rated pressure of the pressurizing module and the plugging module. The pressure collector collects pressure through a pressure sensor and a pressure gauge. Specifically, two groups of pressure sensors are correspondingly arranged on the first pressurizing rod 10 and the second pressurizing rod 18 for pressure collection. The pressure gauge is correspondingly located on the pressurizing tube 2 to collect data on the internal hydraulic pressure, thereby collecting data such as the pressure at the inlet and outlet of the glass tube 3 and the inner wall water pressure, which is used to analyze the water pressure, hydraulic gradient, sliding force, etc. of the karst pipeline filling structure. The pressure collector is connected to a computer, and the data collected by the data collection system can be stored in the computer to facilitate subsequent test data analysis.

[0060] In an optional embodiment, the pressurizing module includes a main frame 9 and a pressurizing tube 2, wherein the main frame 9 is fixed to the surface of the test bench 26 by bolts, and a first pressurizing rod 10 pointing to the glass tube 3 is provided in the middle of the main frame 9. The first pressurizing rod 10 can be any one of a screw, a worm, a hydraulic rod, and a cylinder movable electromagnetic rod. The end of the first pressurizing rod 10 extending into the glass tube 3 is provided with a first piston plate 11. The first piston plate 11 is a square structure corresponding to the inner cavity at the upper end of the glass tube 3, including multiple layers of square plates, and rubber layers are provided between the multiple layers of square plates, or the first piston plate 11 has a certain thickness, and two layers of rubber water stop strips are sleeved on the outer ring of the first piston plate 11 to form a piston structure.

[0061] Thus, a piston structure is formed, and a pressure pipe 2 is provided on the first piston plate 11 for connecting the pressure pipe 2. One end of the pressure pipe 2 is connected to the pressure pump, and the other end passes through the first piston plate 11 and points to the karst pipeline filled with transparent similar material 4, so as to pump high-pressure colored solution between the first piston plate 11 and the karst pipeline filled with transparent similar material 4.

[0062] The pressure pump is mainly composed of an oil pump 15, a water pump 14, an injection pressurizer 13, pipelines and connecting joints. The injection pressurizer 13 is a piston cylinder with a pressure piston on the inner wall. One end of the piston cylinder corresponding to the pressure piston is connected to the oil pump 15, and the other end side wall is connected to the pressure pipe 2 through a three-way valve. The other end of the three-way valve is connected to the water pump 14 through a stop valve and a reversing valve. The water pump 14 is connected to the colored solution holding tank, and a stop valve is provided on the pressure pipe 2 between the three-way valve and the glass tube 3.

[0063] In an optional embodiment, the penetration slit 23 of the plugging module can adjust the slit width, thereby simulating different water seepage crack widths and supporting forces at the outlet of the karst pipeline filling structure by adjusting the width of the penetration slit 23.

[0064] The plugging module includes a second piston plate 19, a second pressure rod 18 and a slide plate 21, wherein the second piston plate 19 is a square plate corresponding to its lower end, and its outer wall is ringed with two layers of rubber water stop strips, which are slidably assembled on the glass tube 3 to form a piston structure. Under the drive of the second pressure rod 18, it resists the transparent similar material 4 filled in the karst pipeline, thereby preventing the transparent similar material 4 filled in the karst pipeline from being displaced. A penetration seam 23 is provided in the middle of the second piston plate 19. The penetration seam 23 is a rectangular hole. A sliding plate 21 is slidably assembled on the penetration seam 23 to adjust the width of the penetration seam 23. The second pressure rod 18 can be any one of a screw, a worm, a hydraulic rod, and a cylinder movable electromagnetic rod.

[0065] The second pressure rod 18 is supported on the corners of the second piston plate 19 via a plurality of claws, so as not to affect the installation and sliding of the slide plate 21 .

[0066] In an optional embodiment, the infiltration seam 23 is a rectangular hole arranged in the middle of the second piston plate 19. The second piston plate 19 is close to a slide groove on one side of the karst pipeline for filling transparent similar material 4. The slide groove is adapted to the length of the infiltration seam 23, so that the slide plate 21 can slide toward the infiltration seam 23 in the slide groove to block the infiltration seam 23, thereby adjusting the infiltration seam 23 by blocking the width of the part. The slide groove is located on one side of the infiltration seam 23, and the depth of the slide groove is adapted to the thickness of the slide plate 21, so that the second piston plate 19 has a flat surface facing the karst pipeline for filling transparent similar material 4, thereby ensuring that the second piston plate 19 can be close to the karst pipeline for filling transparent similar material 4.

[0067] In this embodiment, a folding portion 22 corresponding to the penetration seam 23 is provided on the edge of the slide plate 21. The length of the folding portion 22 is adapted to the length of the penetration seam 23, and the width is adapted to the depth of the penetration seam 23. The side of the folding portion 22 away from the karst pipeline filled with transparent similar material 4 is in the same plane as the side of the second piston plate 19 away from the karst pipeline filled with transparent similar material 4. The side of the second piston plate 19 away from the karst pipeline filled with transparent similar material 4 is provided with a limiting strip 20 corresponding to the folding portion 22, thereby blocking and limiting the folding portion 22 to avoid tilting of the slide plate 21 caused by excessive pressure.

[0068] In an optional embodiment, the flow metering module includes a metering tank 5, a filter screen 6 and an electronic scale 25. The filter screen 6 is arranged above the metering tank 5 to filter out particles in the permeate, and then measure the water quality and particle quality respectively.

[0069] In an optional embodiment, the present application also provides a method for testing the loss of filling particles inside a karst pipe. The test is carried out using any of the above-mentioned test devices, and the water quality and particle quality of the seepage fluid are obtained through the test device, thereby analyzing the permeability coefficient and porosity of the karst pipe filling structure.

[0070] The specific steps include:

[0071] Step S1, vertically placing permeable stone at the bottom of the glass tube 3 and sealing it with a temporary cover plate (with multiple regular small holes drilled therein for drainage).

[0072] Step S2, prepare the transparent similar material 4 for filling the karst pipeline according to the type of filling structure medium, mix 0.5% by mass of multi-walled carbon nanotubes into the transparent similar material 4 for filling the karst pipeline, and then fill it into the glass tube 3 in multiple times, with each filling height of 40mm. After filling, put it into a vacuum box for vacuum treatment for 15 minutes until the filling height reaches 360mm.

[0073] Step S3, fixing the glass tube 3 on the test bench 26 through the fixing steel frame 8, and installing the plugging module and the pressurizing module.

[0074] Step S4, slide the blocking module slide plate 21 to close the permeable seam 23, turn off the colored solution pressure pump, and make the pressure module piston plate close to the karst pipeline filled with transparent similar material 4; apply rated pressure to the pressure module piston plate, so that the transparent similar material filling the pipeline is statically consolidated for a rated time under the rated consolidation pressure.

[0075] Step S5, after the consolidation is completed, the injection pressurizer 13 is connected to the pressurizing tube 2, and the valve between the two is opened, the planar laser is turned on, and the karst pipeline in the glass tube is irradiated with the transparent similar material 4 to form a laser section. The image acquisition device is used to continuously acquire the laser section image in front of the glass tube 3, and the control computer allows the digital camera 1 to perform regular acquisition of the spot plane image, and the acquisition speed is set to 1 frame per second; the data acquisition device and the electronic scale 25 are turned on to collect the pressure of each part and the quality of the permeate; by performing digital photography measurement and analysis on the collected images, the changes in the permeation path of the colored solution and the movement and change rules of the particles inside the karst pipeline filling material are obtained.

[0076] Step S6, adjust the width of the seepage seam 23 to a predetermined value by sliding the slide plate 21 of the plugging module, turn on the pressurizing module and the colored solution pressurizing pump, drive the injection pressurizer 13 through the oil pump 15 to gradually increase the water pressure inside the glass tube 3, pressurize 0.1MPa at each stage, and stabilize the pressure for 600s after pressurization; increase the support pressure value of the second pressurizing rod 18 synchronously according to the applied water pressure value until the designed support pressure is reached. During the step-by-step loading of water pressure, the colored solution is made to seep from the transparent similar material 4 filled in the karst pipeline to the flow metering module, and the seepage liquid is filtered through the filter screen 6 and discharged to the metering tank 5. When the loss particles begin to appear on the filter screen 6, the filter screen 6 is replaced every 60s until the filling structure is damaged by water inrush or instability. The permeability coefficient and porosity of the karst pipeline filling structure are analyzed by the water quality and particle quality of the seepage liquid.

[0077] Step S7, stop the test, turn off the instrument, clean and store the instrument.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A test device for the migration and loss of filling particles inside a karst pipeline, characterized in that: The test device comprises: A glass tube, wherein the glass tube is an L-shaped transparent tube body with two open ends, and the interior of the glass tube is filled with a transparent material similar to the filling of a karst pipeline, which is used to simulate the filling structure material of the karst pipeline; A pressurizing module, wherein the pressurizing module is arranged at one end of the glass tube, a colored solution is arranged between the pressurizing module and the karst pipeline filling material, and the hydraulic coupling effect of the karst pipeline is simulated by pressurizing the colored solution; A plugging module, the plugging module is arranged at the other end of the glass tube, a permeation seam is arranged in the middle of the plugging module, and the permeation seam is connected to the flow metering module through a permeate collecting pipe; A laser irradiation module, which is arranged on the opposite side of the glass tube and the plugging module. The laser irradiation module is a movable red planar laser. The laser irradiates the karst pipe in the glass tube and fills the transparent similar material to form a laser section. An image acquisition device is used in front of the glass tube to continuously collect the laser section image. The pressurizing module is used to apply pressure so that the colored solution seeps from the karst filling material to the flow metering module, and the permeability coefficient and porosity of the karst pipeline filling structure are analyzed by the water quality and particle quality of the seepage liquid; by continuously collecting and digitally photographing and measuring the images of the laser sections of the karst pipeline filling material during the test, the changes in the permeation path of the colored solution and the movement changes of the particles inside the karst pipeline filling material are obtained.

2. The karst pipeline internal filling particle migration and loss test device according to claim 1 is characterized in that: The inner wall of the glass tube is arranged to be an irregular concave-convex surface, and the karst filling material comprises fused quartz sand, amorphous silicon powder, liquid paraffin and n-tridecane.

3. The karst pipeline internal filling particle migration and loss test device according to claim 1, characterized in that: The glass tube is arranged on one side of a fixed steel frame, a bottom support for fixing the test bench is arranged at the bottom of the fixed steel frame, and a diagonal support connected to the bottom support is arranged on one side of the glass tube away from the fixed steel frame.

4. The karst pipeline internal filling particle migration and loss test device according to claim 3 is characterized in that: The diagonal support and the fixed steel frame are provided with a strip hole facing the glass tube in the middle, and the longitudinal length of the strip hole is adapted to the height of the karst filling material. The laser emitted by the planar laser passes through the strip hole and irradiates the transparent similar material filled in the karst pipeline to form a laser section, and the image acquisition device is used to continuously collect the laser section image.

5. The karst pipeline internal filling particle migration and loss test device according to claim 1, characterized in that: The pressurizing module comprises: A main frame, wherein a first pressure rod pointing to the glass tube is provided in the middle of the main frame, and a first piston plate is provided at one end of the first pressure rod extending into the glass tube; A pressure tube, one end of which is connected to a pressure pump, and the other end of which passes through the first piston plate and points to the karst pipeline filling material, so as to pump a high-pressure colored solution between the first piston plate and the karst pipeline filling material.

6. The karst pipeline internal filling particle migration and loss test device according to claim 1, characterized in that: The blocking module comprises: a second piston plate, the second piston plate being slidably mounted on the glass tube to contact the karst pipeline filling material, and a permeable seam being provided in the middle of the second piston plate; A second pressure rod, the second pressure rod being supported on the corners of the second piston plate via a plurality of claws; A slide plate, wherein the second piston plate is close to a slide groove on one side of the karst pipeline filling material, the slide groove is located on one side of the permeable seam, and the depth of the slide groove is matched with the thickness of the slide plate, so that the second piston plate has a flat surface facing the karst pipeline filling material; the width of the permeable seam can be adjusted by sliding the slide plate; The edge of the slide plate is provided with a folded portion corresponding to the permeable seam, and the side of the second piston plate away from the karst pipeline filling material is provided with a limiting strip corresponding to blocking the folded portion.

7. The karst pipeline internal filling particle migration and loss test device according to claim 1, characterized in that: The flow metering module comprises a permeate collecting pipe, a metering tank, a filter screen and an electronic scale. The filter screen is arranged above the metering tank to filter out particles in the permeate.

8. The karst pipeline internal filling particle migration and loss test device according to claim 4, characterized in that: The test device also includes an image acquisition device and a pressure acquisition device correspondingly connected to the controller; The image acquisition instrument is facing the glass tube to continuously acquire the laser section image of the karst pipe filling material inside the glass tube; the pressure acquisition instrument is correspondingly connected to the pressurizing module and the plugging module to acquire the rated pressure data of the pressurizing module and the plugging module.

9. A method for testing the migration and loss of filling particles inside a karst pipeline, the test being carried out by using the test device described in any one of claims 1 to 8, characterized in that: By obtaining the water quality and particle quality of the seepage fluid from the test device, the permeability coefficient and porosity of the karst pipeline filling structure are analyzed; by continuously collecting and digitally photographing the laser section images of the karst pipeline filling material during the test, the changes in the penetration path of the colored solution and the movement of particles inside the filling material are obtained.

10. The method for testing migration and loss of filling particles inside a karst pipeline according to claim 9, characterized in that: The following steps are involved: Step S1, sealing the bottom of the glass tube with a temporary cover plate; Step S2, preparing a transparent similar material for filling the karst pipeline, and mixing the multi-walled carbon nanotubes into the karst pipeline filling material and filling it into the glass tube in multiple times, each filling height is 40 mm, and after filling, the glass tube is placed in a vacuum box for 15 minutes of vacuum treatment until the filling height reaches 360 mm; Step S3, fixing the glass tube on the test bench through a fixed steel frame, and installing the plugging module and the pressurizing module; Step S4, sliding the blocking module slide plate to close the seepage seam; turning off the colored solution pressure pump, so that the pressure module piston plate is closely attached to the karst pipeline filled with transparent similar materials; applying rated pressure to the pressure module piston plate, so that the transparent similar materials filled in the pipeline are statically consolidated for a rated time under the rated consolidation pressure; Step S5, after the consolidation is completed, the planar laser is turned on to irradiate the karst pipeline in the glass tube after being filled with transparent similar materials to form a laser section, and the image acquisition device is used to continuously collect the laser section image in front of the glass tube, and the collected images are digitally photographed, measured and analyzed to obtain the changes in the permeation path of the colored solution and the movement change rules of the particles inside the karst pipeline filling material; Step S6, adjusting the width of the seepage seam to a predetermined value by sliding the slide plate of the plugging module, turning on the pressurizing module and the colored solution pressurizing pump, allowing the colored solution to seep from the top of the karst pipeline filling material to the flow metering module, allowing the seepage liquid to be filtered through the filter screen and then discharged to the metering tank, and analyzing the permeability coefficient and porosity of the karst pipeline filling structure by the water quality and particle quality of the seepage liquid; Step S7, stop the test, turn off the instrument, clean and store the instrument.

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