Method and device for testing three-dimensional flow path of fluidized filling material

Abstract

The invention belongs to the technical field of grouting and filling, and relates to a fluidized filling material three-dimensional flow path test method, which comprises the following steps: constructing a mining space void structure three-dimensional model; printing the mining space void structure three-dimensional model by using a concrete 3D printing technology to obtain a mining space void structure three-dimensional physical similar model; the gangue slurry is injected into the mining space void structure three-dimensional entity similar model, and a final similar model is obtained after the gangue slurry is condensed; and performing transverse slicing treatment on the final similar model, observing the flow diffusion condition of the gangue slurry in the final similar model, and analyzing the flow path of the gangue slurry in the mining space. According to the invention, the flow diffusion condition of the gangue slurry in the mining space can be simulated, and the flow path of the gangue slurry in the mining space can be efficiently and accurately predicted, so that each corner of the mining space can be uniformly and fully filled with the gangue slurry, and the strength and stability of a filling body are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of grouting filling, and relates to a method and device for testing the three-dimensional flow path of fluidized filling materials. Background Art

[0002] The fluidized grouting filling technology is to make solid waste such as gangue and fly ash generated in the process of coal production and utilization into slurry after crushing and grinding, and then transport it to the vicinity of the goaf through long-distance slurry pipeline transportation technology. Then, high-position grouting, adjacent-position grouting or low-position grouting and other technical means are used to fill it into the residual space after the overlying rock of coal mining collapses, so as to achieve the dual purposes of treating solid waste and controlling strata movement. However, the flow of gangue slurry is restricted by the void structure in the mining space, the irregular void distribution in the fracture zone and caving zone formed by coal seam mining, etc., resulting in the flow path of gangue slurry in the mining space becoming difficult to predict.

[0003] At present, due to the lack of a testing device for the flow path of gangue slurry in the mining space, it is difficult to study the flow path of gangue slurry in the mining space, resulting in that it is difficult for gangue slurry to fill every corner of the mining space evenly and sufficiently, reducing the strength and stability of the filling body and affecting the safe production of the mine. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and device for testing the three-dimensional flow path of fluidized filling materials, which can accurately predict the flow path of gangue slurry in the mining space, so that the gangue slurry can fill every corner of the mining space evenly and sufficiently, and improve the strength and stability of the filling body.

[0005] To achieve the above purpose, the technical solution provided by the present invention is as follows: A method for testing the three-dimensional flow path of fluidized filling materials, comprising the following steps: Construct a three-dimensional model of the void structure in the mining space.

[0006] Use concrete 3D printing technology to print a three-dimensional model of the void structure in the mining space, and obtain a three-dimensional physical similarity model of the void structure in the mining space after the concrete sets.

[0007] Inject gangue slurry into the three-dimensional physical similarity model of the void structure in the mining space, and obtain the final similarity model after the gangue slurry sets.

[0008] Perform transverse slicing on the final similarity model, observe the flow and diffusion of gangue slurry inside the final similarity model, and analyze the flow path of gangue slurry in the mining space.

[0009] The characteristics of the present invention also lie in: When constructing a three-dimensional model of the void structure in the mining space, first establish a three-dimensional numerical model of the mining space, analyze the distribution law of the void structure in the overlying strata caused by coal seam mining, eliminate the unconnected isolated voids and separated strata voids, and construct a three-dimensional model of the void structure in the mining space.

[0010] When using concrete 3D printing technology to print a three-dimensional model of the void structure in the mining space, first determine the proportion of the concrete 3D printing material, prepare the concrete 3D printing material according to the proportion of the concrete 3D printing material, and then add the concrete 3D printing material into the concrete 3D printer to print the three-dimensional model of the void structure in the mining space.

[0011] The concrete 3D printing material contains the following substances in parts by weight: 50 to 70 parts of cement, 80 to 120 parts of fine sand, 7 to 9 parts of silica fume, 6 to 8 parts of expansive agent, 1 to 6 parts of double-rapid cement, 1 to 2 parts of water reducing agent, and 20 to 40 parts of water.

[0012] The gangue slurry is composed of gangue and water. The particle size of the gangue is 0.1 mm to 2 mm, and the concentration of the gangue slurry is 50% to 75%.

[0013] When preparing the gangue slurry, 0.5% to 3% of colored ink is added.

[0014] The colored ink is red ink or blue ink.

[0015] A three-dimensional flow path testing device for fluidized filling materials includes: A three-dimensional physical similarity model of the void structure in the mining space.

[0016] A grouting pump, the input end of which is connected to the gangue slurry, and the output end of the grouting pump is connected to the three-dimensional physical similarity model of the void structure in the mining space through a grouting pipeline.

[0017] A pulse damper, which is arranged on the grouting pipeline and is close to the grouting pump in position.

[0018] A detection component, which is arranged on the grouting pipeline and is located between the pulse damper and the three-dimensional physical similarity model of the void structure in the mining space, and is used to detect the flow rate and pressure of the gangue slurry in the grouting pipeline.

[0019] The three-dimensional flow path testing method and device for fluidized filling materials of the present invention have the following advantages: First, by first constructing a three-dimensional model of the goaf space void structure, then using concrete 3D printing technology to print the three-dimensional model of the goaf space void structure, waiting for the concrete to solidify to obtain a three-dimensional physical similarity model of the goaf space void structure, and then injecting gangue slurry into the three-dimensional physical similarity model of the goaf space void structure. After the gangue slurry solidifies, the final similarity model is obtained. Finally, the final similarity model is subjected to transverse slicing to observe the flow and diffusion of the gangue slurry inside the final similarity model, analyze the flow path of the gangue slurry in the goaf space, so as to be able to simulate the flow and diffusion of the gangue slurry in the goaf space, efficiently and accurately predict the flow path of the gangue slurry in the goaf space, make the gangue slurry evenly and fully fill every corner of the goaf space, improve the strength and stability of the filling body, and ensure the safe production of the mine.

[0020] Second, the present invention can effectively promote the application of fluidized grouting filling technology in filling mining, reduce the harm caused by the accumulation of coal gangue, reduce surface subsidence, protect the ecological environment of the mining area, and provide a method reference for similar related technical fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall process structure of the present invention.

[0022] Figure 2 It is a schematic diagram of the three-dimensional model structure of the goaf space void structure in the present invention.

[0023] Figure 3 It is a schematic diagram of the sliced structure of the final similarity model in the present invention.

[0024] Figure 4 It is a schematic diagram of the overall structure of the device in the present invention.

[0025] Reference Signs: 1, grouting pump; 2, pulse damper; 3, pipeline flow meter; 4, pipeline pressure gauge; 5, grouting pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The technical solutions in the present application will be clearly and elaborately described below in conjunction with the accompanying drawings. Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B. The "and / or" in the text is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality" means two or more than two. The following terms "first" and "second" are only for descriptive purposes and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0027] As Figure 1 , Figure 2 , Figure 3 shown, the present invention provides a method and device for testing the three-dimensional flow path of fluidized filling materials, including the following steps: Construct a three-dimensional model of the goaf void structure.

[0028] Use concrete 3D printing technology to print a three-dimensional model of the goaf void structure, and obtain a three-dimensional physical similarity model of the goaf void structure after the concrete hardens.

[0029] Inject gangue slurry into the three-dimensional physical similarity model of the goaf void structure, and obtain the final similarity model after the gangue slurry hardens.

[0030] Perform transverse slicing on the final similarity model, observe the flow and diffusion of the gangue slurry inside the final similarity model, and analyze the flow path of the gangue slurry in the goaf.

[0031] In summary, when predicting the flow path of gangue slurry in the goaf, first construct a three-dimensional model of the goaf void structure, then use concrete 3D printing technology to print a three-dimensional model of the goaf void structure, obtain a three-dimensional physical similarity model of the goaf void structure after the concrete hardens, then inject gangue slurry into the three-dimensional physical similarity model of the goaf void structure, obtain the final similarity model after the gangue slurry hardens, and finally perform transverse slicing on the final similarity model, observe the flow and diffusion of the gangue slurry inside the final similarity model, and analyze the flow path of the gangue slurry in the goaf, so as to efficiently and accurately predict the flow path of gangue slurry in the goaf, enable the gangue slurry to be evenly and fully filled into every corner of the goaf, improve the strength and stability of the filling body, and ensure the safe production of the mine.

[0032] Among them, when constructing the three-dimensional model of the goaf void structure, first establish a three-dimensional numerical model of the goaf, analyze the distribution law of the overlying rock void structure caused by coal seam mining, eliminate the unconnected isolated voids and separated layer voids, and construct the three-dimensional model of the goaf void structure.

[0033] Among them, when using the concrete 3D printing technology to print the three-dimensional model of the goaf void structure, first determine the proportion of the concrete 3D printing material, prepare the concrete 3D printing material according to the proportion of the concrete 3D printing material, and then add the concrete 3D printing material into the concrete 3D printer to print the three-dimensional model of the goaf void structure.

[0034] Among them, the concrete 3D printing material contains the following substances in parts by weight: 50-70 parts of cement, 80-120 parts of fine sand, 7-9 parts of silica fume, 6-8 parts of expansive agent, 1-6 parts of double quick cement, 1-2 parts of water reducing agent and 20-40 parts of water. The proportion of the concrete 3D printing material is a weight ratio.

[0035] Among them, the gangue slurry is composed of gangue and water. The particle size of the gangue is 0.1mm-2mm, and the concentration of the gangue slurry is 50%-75%.

[0036] Among them, 0.5%-3% of colored ink is added when preparing the gangue slurry.

[0037] Among them, the colored ink is red ink or blue ink.

[0038] As Figure 4 shown, the present invention also provides a three-dimensional flow path testing device for fluidized filling materials, including a three-dimensional physical similarity model of the goaf void structure, a grouting pump 1, a pulse damper 2 and a detection component. The input end of the grouting pump 1 is connected to the gangue slurry, the output end of the grouting pump 1 is connected to the three-dimensional physical similarity model of the goaf void structure through a grouting pipeline 5. The pulse damper 2 is arranged on the grouting pipeline 5 and close to the grouting pump 1. The detection component is arranged on the grouting pipeline 5 and between the pulse damper 2 and the three-dimensional physical similarity model of the goaf void structure for detecting the flow rate and pressure of the gangue slurry in the grouting pipeline 5.

[0039] Among them, the detection component includes a pipeline flow meter 3 and a pipeline pressure gauge 4. The pipeline flow meter 3 and the pipeline pressure gauge 4 are arranged on the grouting pipeline 5 and between the pulse damper 2 and the three-dimensional physical similarity model of the goaf void structure.

[0040] Example 1 When predicting the flow path of the gangue slurry in the goaf, the specific steps are as follows: S1. Use the UDEC numerical simulation software to establish a three-dimensional numerical model of the goaf.

[0041] According to the simulation results, disconnected isolated voids and delamination voids were removed, and a three-dimensional model of the goaf space void structure with dimensions of 300 mm × 300 mm × 300 mm in length, width, and height was constructed.

[0042] As Figure 2 shown, four different groups of models were set up. For each group of models, the number and width of internal fissures were changed to make the total volume of internal voids in the model range from 600 ml to 900 ml, with a change gradient of 50 ml. Considering that the discharge line width of the used concrete 3D printer is 18 mm, the minimum diameter of the voids in the model was set to 18 mm.

[0043] S2. Use the CIIC3DPrinter software (Huachuang 3D printer software) to program the similar model of gob filling with gangue in the goaf space. Set the printing line width to 18 mm, the initial thickness to 8 mm, the layer thickness to 8 mm, the filling method to loop filling, the filling density to 1, the crossing angle to 90°, the plane printing speed to 50 mm / s, and the vertical printing speed to 20 mm / s, and import the program into the concrete 3D printer.

[0044] According to the results of the preliminary experiment, while ensuring that the printable concrete of the 3D printer exhibits high fluidity and long setting time during storage, pumping, and extrusion, has sufficient construction time, does not harden in the hopper, and has low fluidity, high wet strength, and high setting and hardening rate after stacking, the weight ratio of the concrete 3D printing material was determined as follows: 60 parts of cement, 100 parts of fine sand, 8 parts of silica fume, 7 parts of expansive agent, 4 parts of double-quick cement, 1 part of water reducer, and 30 parts of water.

[0045] Prepare the concrete 3D printing material according to the ratio, open the printing program, pour the concrete 3D printing material into the printer hopper, and after the printing program runs to completion, wait for the concrete to set to obtain a three-dimensional physical similar model of the goaf space void structure.

[0046] S3. Connect the three-dimensional physical similar model of the goaf space void structure to the grouting pump 1 through the grouting pipeline 5, and sequentially set the pulse damper 2, the pipeline flow meter 3 with a range of 0 L / min to 20 L / min, and the pipeline pressure gauge 4 with a range of 0 MPa to 10 MPa on the grouting pipeline 5 to form a three-dimensional flow path test device.

[0047] Prepare the gangue slurry according to the ratio of the gangue slurry. The gangue slurry is composed of gangue with a particle size of 0.1 mm to 2 mm and water, and the slurry concentration is 65%. At the same time, 1% of red ink is incorporated into the slurry for subsequent observation.

[0048] Inject the gangue slurry into the three-dimensional physical similarity model of the void structure in the mined space. During the grouting process, monitor the grouting pressure and grouting flow rate in real time. Stop the operation of the grouting pump in time when there is slurry overflow or when the grouting volume set in the test plan is reached. After the grouting is completed and the gangue slurry has solidified, the final similarity model is obtained.

[0049] S4. Transversely slice the model after grouting. As Figure 3 shown, observe the flow and diffusion of the slurry inside the model at different positions, and record the grouting pressure and grouting flow rate during the grouting process. Analyze the diffusion distance and diffusion radius of the gangue slurry in the model according to the slicing results. The test results are shown in Table 1.

[0050] Table 1 shows the slurry injection conditions for each working condition

[0051] As can be seen from Table 1, the relationship between the maximum grouting pressure, the farthest diffusion distance, and the maximum diffusion radius during the injection process of the gangue slurry and the injection volume / void volume of the model can be observed. Analyzing Table 1 shows that during the grouting process, the farthest diffusion distance of the slurry increases with the increase of the void volume in the model, the maximum diffusion radius decreases with the increase of the void volume in the model, and the maximum diffusion radius of the slurry decreases to a certain extent with the increase of the slurry injection volume. Thus, the flow path of the gangue slurry in the mined space can be predicted efficiently and accurately through the flow law of the gangue slurry in the mined space.

[0052] It can be understood that the present invention is described through some embodiments. Those skilled in the art know that without departing from the spirit and scope of the present invention, various changes or equivalent replacements can be made to these features and embodiments. In addition, under the teaching of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope protected by the present invention.

Claims

1. A three-dimensional flow path testing method for fluidized filling materials, characterized in that It includes the following steps: Construct a three-dimensional model of the goaf space void structure; Use concrete 3D printing technology to print the three-dimensional model of the goaf space void structure. After the concrete solidifies, obtain a three-dimensional physical similarity model of the goaf space void structure; Inject the gangue slurry into the three-dimensional physical similarity model of the goaf space void structure. After the gangue slurry solidifies, obtain the final similarity model; Perform transverse slicing on the final similarity model, observe the flow and diffusion of the gangue slurry inside the final similarity model, and analyze the flow path of the gangue slurry in the goaf space.

2. The three-dimensional flow path testing method of the fluidized filling material according to claim 1, characterized in that When constructing the three-dimensional model of the goaf space void structure, first establish a three-dimensional numerical model of the goaf space, analyze the distribution law of the overlying rock void structure caused by coal seam mining, eliminate the unconnected isolated voids and separation voids, and construct the three-dimensional model of the goaf space void structure.

3. The three-dimensional flow path testing method of the fluidized filling material according to claim 1, characterized in that When using concrete 3D printing technology to print the three-dimensional model of the goaf space void structure, first determine the proportion of the concrete 3D printing material, prepare the concrete 3D printing material according to the proportion of the concrete 3D printing material, and then add the concrete 3D printing material into the concrete 3D printer to print the three-dimensional model of the goaf space void structure.

4. The three-dimensional flow path testing method of the fluidized filling material according to claim 3, wherein The concrete 3D printing material contains the following substances in parts by weight: 50 to 70 parts of cement, 80 to 120 parts of fine sand, 7 to 9 parts of silica fume, 6 to 8 parts of expansive agent, 1 to 6 parts of double-quick cement, 1 to 2 parts of water reducing agent, and 20 to 40 parts of water.

5. The three-dimensional flow path testing method of the fluidized filling material according to claim 1, characterized in that The gangue slurry is composed of gangue and water. The particle size of the gangue is 0.1mm to 2mm, and the concentration of the gangue slurry is 50% to 75%.

6. The three-dimensional flow path testing method for the fluidized filling material according to claim 1, wherein Add 0.5% to 3% of colored ink when preparing the gangue slurry.

7. The three-dimensional flow path testing method of the fluidized filling material according to claim 6, characterized in that The colored ink is red ink or blue ink.

8. A three-dimensional flow path testing device for fluidized filling materials, characterized in that, Adopt the three-dimensional flow path test method of the fluidized filling material as described in claim 1, including: A three-dimensional physical similarity model of the goaf space void structure; A grouting pump (1), the input end is connected to the gangue slurry, and the output end of the grouting pump (1) is connected to the three-dimensional physical similarity model of the goaf space void structure through a grouting pipeline (5); A pulse damper (2), arranged on the grouting pipeline (5) and close to the grouting pump (1); A detection component, arranged on the grouting pipeline (5) and between the pulse damper (2) and the three-dimensional physical similarity model of the goaf space void structure, and used to detect the flow rate and pressure of the gangue slurry in the grouting pipeline (5).

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