Coal gangue precise adaptive filling method based on working face mine pressure regulation and control

Abstract

The application discloses a coal gangue precision self-adaptive filling method based on working face mine pressure regulation and control, and comprises the following steps: step one, stress distribution data above a filling hydraulic support and in front of a working face in a mining process is obtained by using FLAC3D numerical simulation software, a nonlinear relationship between the stress above the filling hydraulic support and the stress in front of the working face is established, so that the working face front mine pressure distribution can be inversed by inputting the support load; step two, the stress peak value is determined according to the inversed working face front mine pressure distribution data, and a stress concentration area position is warned; step three, a goaf key filling position is decided according to the warned stress concentration area position; step four, filling is implemented by using a coal gangue filling device according to the decided goaf key filling position. The goaf key filling position is decided by using the application, the mine pressure is controlled in a range that neither coal and rock dynamic disasters nor coal wall spalling occurs, and coal can be broken without gangue.

Description

TECHNICAL FIELD

[0001] The present application relates to a coal gangue precision adaptive filling method based on working face mine pressure regulation. BACKGROUND

[0002] Most of the coal seams in China contain one or more layers of gangue, and the thickness of the gangue in some mines can even reach 2m. From the working face tendency, due to the superimposed influence of the working face advance support pressure and the roadway lateral support pressure, there is a stress peak area in front of the working face, the mining stress generally presents a "single peak" state, the mining stress distribution of the deep and long working face presents a "three peak" state, and has a dynamic migration characteristic. Related research shows that filling in the goaf can reduce the stress concentration degree and strain energy density of the working face, realize stress transfer, and prevent coal and gas outburst and other coal and rock dynamic disasters.

[0003] Therefore, if the stress in the stress peak area of the working face is controlled between the strength limits of the coal gangue by filling in the key position of the goaf, the coal reaches the strength limit damage but the gangue has not been damaged, not only can the coal and rock dynamic disasters and coal wall spalling caused by stress concentration be prevented, but also the cracks in the coal body are more than the gangue, and the broken size after cutting is smaller, and when the coal gangue size is obviously different, it will be more conducive to the implementation of subsequent coal gangue separation. SUMMARY

[0004] In view of the above problems, the present application provides a coal gangue precision adaptive filling method based on working face mine pressure regulation, which aims to reduce the stress concentration of the working face, prevent coal and rock dynamic disasters, and break coal without breaking gangue. The underground gangue is precisely filled in the key position of the goaf, realizing the organic combination of gangue treatment and mine pressure control.

[0005] In order to achieve the above technical purpose and achieve the above technical effect, the present application realizes the following technical scheme:

[0006] The coal gangue precision adaptive filling method based on working face mine pressure regulation comprises the following steps:

[0007] Step one, use FLAC3D numerical simulation software to obtain the stress distribution data above the filling hydraulic support and in front of the working face during the mining process, establish a nonlinear relationship between the stress above the filling hydraulic support and the stress in front of the working face, so that the support load can be input to inverse the mine pressure distribution in front of the working face;

[0008] Step two, determine the stress peak value according to the inverse mine pressure distribution data in front of the working face, and warn the stress concentration area position;

[0009] Step three, decide the key filling position of the goaf according to the warned stress concentration area position;

[0010] Step four, according to the decision of the key goaf filling position, using coal gangue filling device to implement filling.

[0011] Preferably, step one specifically comprises the following steps:

[0012] Step 101, according to the mining engineering geology conditions to establish FLAC 3D three-dimensional numerical calculation model;

[0013] Step 102, according to the measured stress value above the filling hydraulic support to estimate the range of mine boundary load parameters, wherein the boundary load parameters have 5: gravity acceleration correction coefficient a g , the boundary normal stress parameters a1, b1 perpendicular to the model length direction, the boundary normal stress parameters a2, b2 perpendicular to the model width direction; from the estimated boundary load parameter range, 5 values are selected at equal intervals, and the boundary load parameter combination is constructed by using the orthogonal test design method, 5 factors and 5 levels of orthogonal experiment are used, and 25 groups are formed;

[0014] Step 103, set the boundary load stress value as σ1, σ2, wherein σ1=a1h+b1, σ2=a2h+b2; h is the buried depth; 25 groups of σ1, σ2, a g are substituted into FLAC3D numerical simulation software for numerical simulation calculation, and the calculation results of the stress above the τ filling hydraulic supports under different parameters are obtained;

[0015] Step 104, according to the numerical calculation results of the ground stress field, the stress calculation values above the filling hydraulic supports under each group of boundary load parameters are extracted, and a learning sample library of input boundary load parameters and output stress calculation values above the τ filling hydraulic supports is constructed;

[0016] Step 105, learning and training the learning sample library obtained in step 104 by using deep neural network, and establishing a nonlinear mapping relationship between the input boundary load parameters and the output stress values above the τ filling hydraulic supports;

[0017] Step 106, convert input and output, so that the input stress values above the τ filling hydraulic supports output the boundary load parameters;

[0018] Step 107, input the stress values above the τ filling hydraulic supports monitored on site into the deep neural network, load the output optimal boundary load parameters into the FLAC 3D three-dimensional numerical calculation model for calculation, and obtain the mine pressure distribution data in front of the working face at this time under the stress combination of the filling hydraulic support.

[0019] Preferably, step two specifically comprises the following steps:

[0020] Step 201, search the maximum stress value M from the calculated stress distribution data in front of the working face, the value of M is the stress peak, and the position of M is recorded as (x m ,y m );

[0021] Step 202, search the stress values greater than σ b1 from the calculated stress distribution data in front of the working face in turn, record them as N1, N2, N3, and their positions as (x1, y1), (x2, y2), (x3, y3), and so on.

[0022] Wherein, σ b1 is the stress critical value in the slow development stage of fracture and the stable expansion of fracture in the uniaxial compression experiment of coal body;

[0023] Step 203, pre-alarm the positions of M, N1, N2, N3, and so on.

[0024] Preferably, step three specifically includes the following steps:

[0025] Step 301, input the orthogonal combination of filling positions L1, L2, L3, and so on into the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameters in step 107 to perform calculation, obtain the stress distribution data in front of the working face under the filling position combination, and establish an empirical knowledge base;

[0026] Wherein, the working face is divided into multiple filling areas from the end to the end, and each adjacent 3 hydraulic support is a filling area, recorded as L1, L2, L3, and so on.

[0027] Step 302, according to the positions and sizes of M, N1, N2, N3, and so on pre-alarmed in step 203, find the filling position combination scheme L 充 from the empirical knowledge base, wherein the stress at the position is lower than σ b1 ;

[0028] Step 303, input the filling position, filling height, and filling body strength in the filling position combination scheme as input quantities, load them into the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameters in step 107 to perform calculation, and obtain the new stress distribution data M', N1', N2', N3', and so on at the positions of M, N1, N2, N3, and so on in front of the working face;

[0029] Step 304, when M', N1', N2', N3', and so on are all less than σ b1 , then the filling position combination scheme L 充 is the best filling scheme.

[0030] Preferably, step four specifically comprises the following steps:

[0031] Step 401, the gangue is transported to the working face filling transfer machine transition bin through the gangue conveying belt, when the gangue in the working face filling transfer machine transition bin meets the filling condition, the filling transfer machine is started to transport the gangue to the bottom discharge scraper conveyor to start filling;

[0032] Step 402, the bottom discharge scraper conveyor unloads the gangue to the multi-angle gangue throwing belt, the gangue is thrown to the flexible filling bag by the multi-angle gangue throwing belt, the speed and angle of the multi-angle gangue throwing belt are adjusted to make the gangue layer by layer and fully fill the filling space, wherein, every time a layer of gangue is fully filled, the grouting device is used to inject the cementing agent into the flexible filling bag; wherein, during the process of layer by layer and fully filling the gangue in the filling space, the self-standing time T of the filling body 充 is less than the next time of the moving support period T of the filling hydraulic support 周 .

[0033] Preferably, in step 103, the filling hydraulic support is 10 filling hydraulic supports selected at equal intervals in the working face.

[0034] Preferably, in step 304, if the optimal filling scheme is not obtained, a new filling position combination scheme is obtained again in step 302 until the optimal filling scheme is obtained.

[0035] Preferably, the cementing agent is a cement water glass solution or a mixture of a water glass solution and a calcium chloride solution.

[0036] The beneficial effects of the present application are:

[0037] The precise self-adaptive filling of the present application, wherein the precision means that the filling method can prewarn the stress peak value area in front of the working face according to the real-time distribution of the mine pressure in front of the working face, and use the present application to decide the key filling position of the goaf, so as to control the mine pressure in a range that neither produces coal and rock dynamic disaster nor coal wall spalling, and realizes the range of breaking coal without breaking gangue. The self-adaptation is relative to the dynamic migration of the stress peak value of the working face, and can adjust the filling scheme synchronously according to the real-time distribution of the stress in front of the working face and the migration of the stress peak value. Through the present application, the intelligent in-situ filling of coal and gangue can be realized, which not only can reduce the carbon dioxide emission caused by the spontaneous combustion of the ground gangue mountain, reduce the energy resource consumption per unit output, form an effective carbon emission control valve at the source of production, but also can eliminate the stress concentration of the working face by using the gangue filling, prevent the coal and rock dynamic disaster, and realize the green and low-carbon intelligent mining of coal. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a schematic diagram of the overall arrangement of the present application;

[0039] Figure 2is a structural schematic diagram of a coal gangue filling device of the present application;

[0040] Figure 3 is a structural schematic diagram of a flexible filling bag of the present application;

[0041] Figure 4 is a flow chart of a preferred filling embodiment of the present application;

[0042] The labels of the drawings have the following meanings:

[0043] 1. coal mining machine; 2. filling hydraulic support; 3. goaf; 4. filling body; 5. grouting device; 6. bottom discharge scraper conveyor; 7. multi-angle gangue throwing belt; 8. telescopic gangue blocking plate; 9. support tail beam; 10. distance measuring device; 11. working face filling transfer machine transition bin; 12. flexible filling bag; 13. pressure sensor. DETAILED DESCRIPTION

[0044] The technical solutions of the present application will be described in further detail below in combination with the drawings and specific embodiments, so that those skilled in the art can better understand the present application and implement it, but the embodiments are not limiting to the present application.

[0045] The coal gangue precise self-adaptive filling method based on working face mine pressure regulation and control comprises the following steps:

[0046] Step one, to invert the mine pressure distribution in front of the working face in real time and provide decision basis for intelligent gangue filling, the stress distribution data above the filling hydraulic support 2 and in front of the working face in the mining process is obtained by using FLAC3D numerical simulation software, a nonlinear relationship between the stress above the filling hydraulic support 2 and the stress in front of the working face is established, so that the input support load can invert the mine pressure distribution in front of the working face.

[0047] FLAC 3D (Fast Lagrangian Analysis of Continua) is a simulation calculation software developed by the American ITASCA company, which can simulate the stress characteristics of three-dimensional structures of soil, rock and other materials and analyze plastic flow, specifically, step one comprises the following steps:

[0048] Step 101, establishing a FLAC 3D three-dimensional numerical calculation model according to the mining engineering geological conditions of the mine;

[0049] Step 102, estimating the mine boundary load parameter range according to the measured stress value above the filling hydraulic support 2, wherein the boundary load parameters have five: gravity acceleration correction coefficient a g, the boundary normal stress parameters a1, b1 (a1, b1 correspond to the two sides perpendicular to the length direction of the model respectively), the boundary normal stress parameters a2, b2 (a2, b2 correspond to the two sides perpendicular to the width direction of the model respectively) ; 5 values are selected from the estimated boundary load parameter range at equal intervals, and the boundary load parameter combinations are constructed by using the orthogonal test design method. 5-factor 5-level orthogonal experiment is adopted, and 25 groups are formed.

[0050] Step 103, set the boundary load stress value as σ1, σ2, wherein σ1=a1h+b1, σ2=a2h+b2; h is the buried depth; 25 groups of σ1, σ2, a g Substitute into the FLAC3D numerical simulation software for numerical simulation calculation, and obtain the calculation results of the stress above the τ filling hydraulic supports 2 under different parameters.

[0051] Preferably, the filling hydraulic support 2 is 10 filling hydraulic supports 2 selected at equal intervals in the working face. Since the number of filling hydraulic supports 2 is too large, the data calculation is huge and the efficiency is low under uniform sampling, therefore, τ filling hydraulic supports 2 can be selected at equal intervals according to the actual situation of the mine for sampling, and the value of τ is preferably 10.

[0052] Step 104, according to the numerical calculation results of the ground stress field, extract the stress calculation values above the filling hydraulic support 2 under each group of boundary load parameters, and construct a learning sample library of input boundary load parameters and output stress calculation values above the τ filling hydraulic supports 2.

[0053] Step 105, learn and train the learning sample library obtained in step 104 by using the deep neural network, and establish a nonlinear mapping relationship between the input boundary load parameters and the output stress values above the τ filling hydraulic supports 2.

[0054] Step 106, convert the input and output, so that the input stress values above the τ filling hydraulic supports 2 are outputted as the boundary load parameters, and the value of τ is preferably 10.

[0055] Step 107, input the stress values above the τ filling hydraulic supports 2 (monitored by the pressure sensor 13, Figure 2 Step 107, input the stress values above the τ filling hydraulic supports 2 (monitored by the pressure sensor 13,

[0056] Step two, according to the inversion of the working face front mine pressure distribution data, determine the stress peak value, and early warning stress concentration area position, for the adjustment of coal mining technology, filling scheme provides the basis, namely according to the different real time adjustment of mine pressure distribution of coal mining filling scheme, its steps are as follows:

[0057] Step 201, search the maximum stress value M from the calculated working face front mine pressure distribution data, M value is the stress peak value, record M position as (x m ,y m );

[0058] Step 202, search the stress value greater than σ b1 from the calculated working face front mine pressure distribution data, in turn recorded as N1, N2, N3,..., the position is recorded as (x1, y1), (x2, y2), (x3, y3),...

[0059] Wherein, σ b1 is the stress critical value of the slow development stage and the stable expansion of the crack in the uniaxial compression test of coal body; when the stress in the coal body is less than σ b1 , new cracks are generated in the coal body and show no impact danger state.

[0060] Step 203, early warning of M, N1, N2, N3,...

[0061] Step three, according to the position of the early warning stress concentration area, the key filling position of the goaf 3 is decided; after filling in this position, the advanced support pressure can be controlled in the range of not producing coal and rock dynamic disaster, and realizing the broken coal without broken gangue, so as to control the advanced support pressure by filling to pre-crack the coal body (it has been proved by experiment that the crack is first generated in the coal in the coal and rock combination), so that the coal body after cutting by the coal mining machine is smaller than the thickness of the gangue, which is convenient for subsequent coal and gangue underground separation, relieves the separation pressure, and improves the separation efficiency. Its steps are as follows:

[0062] Step 301, the orthogonal combination of filling position L1, L2, L3,... is input to the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameter in step 107, the working face front mine pressure distribution data under the filling position combination is obtained, and the experience knowledge base is established;

[0063] Wherein, the working face is divided into multiple filling areas from the end to the end, such as every adjacent 3 filling hydraulic support 2 is 1 filling area, recorded as L1, L2, L3,...

[0064] Step 302, according to the position and size of M, N1, N2, N3,... early warned in step 203, find the stress lower than σb1 the filling position combination scheme L 充 ;

[0065] Step 303, taking the filling position, filling height, and filling body 4 strength in the filling position combination scheme as input quantities, loading into the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameter in step 107 to perform calculation, obtaining new mine pressure distribution data M', N1', N2', N3' at the M, N1, N2, N3... positions in front of the working face;

[0066] The filling height and the filling body strength are fixed values, wherein the filling height is equal to the coal seam mining height, and the filling body strength is the material itself characteristics. Since the precise adaptive filling method needs to adjust the filling position synchronously with the stress peak value migration, the filling body is required to achieve self-standing in a short time and to support the roof to a certain strength. After comprehensive consideration, the method of cementing the bulk gangue is adopted for filling, and the filling material adopts the cement water glass solution or the mixed solution of the water glass solution and the calcium chloride solution, which has the characteristics of high bonding strength, good heat resistance, strong acid resistance, and short setting time.

[0067] Step 304, when M', N1', N2', N3' are all less than σ b1 , then the filling position combination scheme L 充 is the best filling scheme. If the best filling scheme is not obtained, then a new filling position combination scheme is obtained in step 302 until the best filling scheme is obtained.

[0068] Step four, as shown in Figure 1 , according to the decision of the key filling position of the goaf 3, the coal gangue filling device can be used for filling, and intelligently cooperates with each filling process, so that the time used for the entire filling process from the start of filling to the self-standing of the filling body is less than the moving period of the filling hydraulic support, realizing that the front coal mining and the rear filling do not affect each other, achieving the purpose of coordinated mining and filling and efficient filling. The specific steps are as follows:

[0069] Step 401, the gangue is transported to the working face filling transfer machine transition bin 11 by the gangue transportation belt, and when the gangue in the working face filling transfer machine transition bin 11 meets the filling conditions (such as the weight is greater than 30 kg), the filling transfer machine starts to transport the gangue to the bottom discharge scraper conveyor 6 to start filling;

[0070] Step 402, the bottom discharge scraper conveyor 6 discharges the gangue to the multi-angle gangue throwing belt 7, and the multi-angle gangue throwing belt 7 throws the gangue into the flexible filling bag 12 (the flexible filling bag 12 is an open non-closed structure), and the gangue is evenly laid and filled in the filling space by adjusting the belt speed and angle of the multi-angle gangue throwing belt 7, wherein each time a layer of gangue is laid, the grouting device 5 is used to inject the cementing agent into the flexible filling bag 12, so that the bulk gangue is coagulated into a whole to support the roof. The belt speed and angle of the multi-angle gangue throwing belt 7 are calculated according to the size of the flexible filling bag, and the existing technology can be used for calculation.

[0071] Wherein, in order to achieve the coordination of mining and filling, and realize the mutual non-influence of the front coal mining and the rear filling, the self-standing time T 充 of the filling hydraulic support 2 is less than the next moving support period T 周 :

[0072]

[0073] In the formula, T 周 is the next moving support period of the filling hydraulic support; L 工 is the length of the working face; v 采 is the cutting speed of the coal mining machine 1; T 空 is the time for the coal mining machine 1 to return after cutting a knife.

[0074] Correspondingly, as shown in Figure 2 , the coal gangue precise self-adaptive filling device based on the working face mine pressure regulation includes a filling hydraulic support 2, one pressure sensor 13 is installed at the center of the top beam and the tail beam of the filling hydraulic support 2, and the average value of the two is taken as the stress value above the filling hydraulic support 2, the bottom of the support tail beam 9 of the filling hydraulic support 2 is provided with a bottom discharge scraper conveyor 6 and a grouting device 5, and the position of the support tail beam 9 located at the opening of the flexible filling bag 12 is provided with a distance measuring device 10, such as an infrared distance measuring instrument, a binocular synchronous camera, etc., for measuring the filling height during the filling process. Among them, the grouting device 5 can be four nozzles with spraying function, which are evenly distributed above the opening of the flexible filling bag 12. The bottom of the bottom discharge scraper conveyor 6 is provided with a multi-angle gangue throwing belt 7, the bottom of the multi-angle gangue throwing belt 7 and the bottom of the filling hydraulic support 2 are provided with a telescopic gangue blocking plate 8, and the telescopic gangue blocking plate 8 and the filling area are provided with a flexible filling bag 12, as shown in Figure 3As shown, one end face of the flexible filling bag 12 is a movable face, that is, a zipper is provided along the height direction, and in the filling process, the telescopic gangue blocking plate 8 drives the zipper to move upward, so that the movable face of the flexible filling bag 12 is adaptively adjusted to a suitable height (correspondingly, the precise adaptive filling method of the application also adopts this scheme in the filling process), which facilitates filling and ensures filling quality, wherein the coal gangue precise adaptive filling device adopts any one of the filling methods described above.

[0075] Among them, the flexible filling bag 12 is made of soft material.

[0076] The following will be combined Figure 4 Introduce a filling method embodiment for adaptively adjusting the movable face of the flexible filling bag 12 to a suitable height, including the following steps:

[0077] S01, hang the hanging hole of the flexible filling bag on the clamp of the support tail beam, and hang the hanging ring of the zipper on the telescopic column of the telescopic gangue blocking plate;

[0078] S02, according to the height of the flexible filling bag, divide it into φ sections from bottom to top, and each section height is H 模 , respectively recorded as L1, L2……L 启 ……L 终 layer, wherein L 启 =floor(H 链 / H 模 ), floor is a floor function, H 链 is the distance from the bottom of the zipper to the bottom of the flexible filling bag;

[0079] S03, the mined gangue is transported to the working face filling transfer machine transition bin by the gangue conveying belt, and the gangue is screened by the vibrating screen before entering the working face filling transfer machine transition bin, the large gangue enters the upper layer of the filling transfer machine transition bin, and the small gangue enters the lower layer of the filling transfer machine transition bin;

[0080] S04, initialize Li=1, and enter step S05;

[0081] S05, the working face filling transfer machine starts to transfer the large gangue in the transition bin, and enters step S06;

[0082] S06, throw the gangue to the rear end of the flexible filling bag, and throw from left to right in a cycle, and gradually reduce the belt speed until the filling reaches the front end of the flexible filling bag, and enter step S07;

[0083] S07, judge whether the layer laying height is ≥80%*H 模 , if greater, enter step S08, otherwise enter step S06;

[0084] S08, the working face filling transfer machine starts to transfer the small gangue in the transition bin, and enters step S09;

[0085] S09, gangue is thrown to the rear end of the flexible filling bag, and is thrown from left to right in a cycle, and the speed is gradually reduced until the filling reaches the front end of the flexible filling bag, and enters step S10;

[0086] S10, whether the laying height of the layer is equal to H 模 , if yes, enter step S11, otherwise, enter step S09;

[0087] S11, stop transporting and throwing gangue, start the grouting device to grout until the liquid level of the cementing agent is greater than or equal to 10% of the filling height of the next layer, then stop grouting, the value of Li is increased by 1, and enter step S12;

[0088] S12, whether Li is greater than or equal to L 启 , if yes, enter step S13, otherwise, enter step S05;

[0089] S13, whether Li is equal to L 终 , if yes, enter step S14, otherwise, the movable end of the telescopic baffle is lifted to 30% of the filling height of the next layer and enters step S05;

[0090] S14, the movable end of the telescopic baffle is lifted to 70% of the filling height of the layer, the working face filling transfer machine starts to transfer the large gangue in the transition bin, and enters step S15;

[0091] S15, gangue is thrown to the rear end of the flexible filling bag, and is thrown from left to right in a cycle, and the speed is gradually reduced until the filling reaches the front end of the flexible filling bag, and enters step S16;

[0092] S16, whether the laying height of the layer is greater than or equal to 50%*H 模 , if yes, enter step S17, otherwise, enter step 15;

[0093] S17, the working face filling transfer machine starts to transfer the small gangue in the transition bin, and throws gangue to the flexible filling bag until the laying height of the middle and rear end reaches 90% of the laying height of the layer and the front end has gangue leakage, stops transporting and throwing gangue, the movable end of the telescopic baffle is lifted to the top end, the grouting device is started to grout, and enters step S18;

[0094] S18, the grouting of the cementing agent is terminated when the liquid level reaches the top end.

[0095] During the filling process, the filling height is judged according to the goaf filling condition monitored by the distance measuring device in real time, the movable end height of the telescopic gangue blocking plate is adaptively adjusted, the zipper height of the flexible filling bag is adjusted, the movable structure height of the flexible filling bag is consistent with the movable end height of the telescopic gangue blocking plate, so that better sealing and shaping effects are achieved. The process is simple, convenient to operate, does not need to dig a large-section chamber in the underground, and does not cause environmental pollution and water pollution.

[0096] The beneficial effects of the present application are:

[0097] (1) The precise adaptive filling method aims at reducing stress concentration in front of the working face, preventing coal and rock dynamic disasters, and breaking coal without breaking gangue, and precisely and intelligently fills the gangue in the key position of the goaf underground, so that the organic combination of gangue treatment and mine pressure control is realized. Through the method, in-situ green intelligent filling of coal gangue can be realized, which can not only reduce carbon dioxide emission caused by spontaneous combustion of ground gangue mountain, reduce energy resource consumption per unit output, form an effective carbon emission control valve at the source of production, but also eliminate stress concentration of the working face by using gangue filling, prevent coal and rock dynamic disasters, and realize green and low-carbon intelligent mining of coal.

[0098] (2) The present application uses a three-dimensional mine pressure intelligent inversion system based on a deep neural network algorithm to inversely calculate the mine pressure distribution in front of the working face in real time, uses a pressure sensor arranged above the filling hydraulic support of the working face to monitor the stress above the hydraulic support in real time, inversely calculates the real-time distribution of the mine pressure in front of the working face through the complex nonlinear relationship between the working resistance of the filling hydraulic support and the mine pressure in front of the working face, and provides a basis for adjusting the filling scheme by warning the position of the stress concentration area and determining the size of the stress peak.

[0099] (3) According to the position of the stress concentration area and the stress concentration degree, the present application decides the key filling position of the goaf, so that the advanced abutment pressure is controlled in a range in which coal and rock dynamic disasters are not caused and coal is broken without gangue after filling in the position. Thus, the coal body is pre-cracked by filling to control the advanced abutment pressure, the coal body block size after being cut by the coal mining machine is smaller than the gangue block size, the subsequent coal and gangue separation is facilitated, the separation pressure is relieved, and the separation efficiency is improved.

[0100] (4) The present application can command the filling hydraulic support at the corresponding position to implement filling according to the decided key filling position of the goaf, and intelligently cooperates with each filling process, so that the time used for the whole filling process from the beginning of filling to the self-standing of the filling body is less than the moving period of the filling hydraulic support, the front coal mining and the rear filling do not affect each other, the purpose of coordinated mining and filling and efficient filling is achieved.

[0101] (5) During the filling process, the telescopic gangue blocking plate drives the zipper to move upward, the movable surface of the flexible filling bag is adaptively adjusted to a suitable height, filling is facilitated, and the filling quality is ensured.

[0102] The above merely describes the preferred embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, which is made according to the content of the present application specification and drawings, is also included in the patent protection scope of the present application.

Claims

1. A coal gangue precision adaptive filling method based on working face mine pressure regulation, characterized in that, Comprise the following steps: Step one, using FLAC3D numerical simulation software to obtain the stress distribution data above the filling hydraulic support (2) and in front of the working face in the mining process, establish the nonlinear relationship between the stress above the filling hydraulic support (2) and the stress in front of the working face, so that the input support load can be inverted to obtain the stress distribution data in front of the working face; Step two, according to the inversion of the stress distribution data in front of the working face, determine the stress peak value and the position of the stress concentration area; Step three, according to the position of the stress concentration area, decide the key filling position of the goaf (3); Step four, according to the decision of the key filling position of the goaf (3), use the coal gangue filling device to implement the filling; Step one specifically comprises the following steps: Step 101, according to the engineering geological conditions of the mining well, establish a FLAC 3D three-dimensional numerical calculation model; Step 102, estimating the range of mine boundary load parameters according to the measured stress value above the filling hydraulic support (2), wherein the boundary load parameters have five parameters: gravity acceleration correction coefficient a g , boundary normal stress parameters a1, b1 perpendicular to the length direction of the model, and boundary normal stress parameters a2, b2 perpendicular to the width direction of the model; 5 values are selected from the estimated range of boundary load parameters at equal intervals, and the method of orthogonal test design is used to construct the combination of boundary load parameters, and 5-factor 5-level orthogonal experiment is used, and a total of 25 groups are formed; Step 103, set the boundary load stress value as σ1 and σ2, wherein σ1=a1h+b1, σ2=a2h+b2; h is the buried depth; 25 groups of σ1, σ2, a g Substitute into the FLAC3D numerical simulation software for numerical simulation calculation, and obtain the calculation results of the stress above the τ filling hydraulic support (2) under different parameters; Step 104, according to the numerical calculation results of the stress field, extract the stress calculation value of the filling hydraulic support (2) under each group of boundary load parameters, and construct the learning sample library of input boundary load parameters and output stress calculation value of τ filling hydraulic support (2) above; Step 105, use deep neural network to learn and train the learning sample library obtained in step 104, and establish the nonlinear mapping relationship between the input boundary load parameters and the output stress value of τ filling hydraulic support (2) above; Step 106, convert input and output, so that the input stress value of τ filling hydraulic support (2) above outputs the boundary load parameter; Step 107, input the stress value of τ filling hydraulic support (2) above monitored on site into the deep neural network, load the output optimal boundary load parameter into the FLAC 3D three-dimensional numerical calculation model for calculation, and obtain the stress distribution data of the working face in front of the filling hydraulic support (2) at this time under the stress combination.

2. The coal gangue precision adaptive filling method based on working face mine pressure regulation according to claim 1, characterized in that, Step two specifically comprises the following steps: Step 201: Search for the maximum stress value M from the calculated mine pressure distribution data ahead of the working face. The value of M is the stress peak value. The position of M is denoted as (x...). m ,y m ); Step 202, search for stress values greater than σ from the calculated working face front mine pressure distribution data b1 The stress values are sequentially recorded as N1, N2, N3, and so on, and their positions are recorded as (x1, y1), (x2, y2), (x3, y3), and so on. where σ b1 is the stress threshold value of the slow development stage and stable expansion of the crack in the uniaxial compression test of the coal body. Step 203, the position of M, N1, N2, N3...... is warned.

3. The coal gangue precision adaptive filling method based on working face mine pressure regulation and control according to claim 2, characterized in that, Step three specifically comprises the following steps: Step 301, take the orthogonal combination of filling positions L1, L2, L3...... as input, load into the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameter in step 107, calculate the working face in front of the filling position combination, and obtain the working face in front of the filling position combination. The stress distribution data are established to establish the experience knowledge base; Wherein, the working face is divided into multiple filling areas from the end to the end, and each adjacent 3 filling hydraulic supports (2) are a filling area, which is denoted as L1, L2, L3......; Step 302: Based on the location and magnitude of M, N1, N2, N3... as warned in Step 203, search the experience knowledge base to find locations where the stress is always lower than σ. b1 Filling location combination scheme L 充 ; Step 303, take the filling position, filling height, and filling body (4) strength in the filling position combination scheme as input, load into the FLAC 3D three-dimensional numerical calculation model under the optimal boundary load parameter in step 107, calculate the new stress distribution data M', N1', N2', N3'...... of M, N1, N2, N3...... in front of the working face; Step 304, when M', N1', N2', N3'... are all less than σ b1 , then the filling position combination scheme L 充 is the best filling scheme.

4. The coal gangue precision adaptive filling method based on working face mine pressure regulation according to claim 1, characterized in that, Step four specifically comprises the following steps: Step 401, the gangue is transported to the working face filling transfer machine transition bin (11) through the gangue conveying belt, when the gangue in the working face filling transfer machine transition bin (11) meets the filling condition, the filling transfer machine is started to transport the gangue to the bottom discharge scraper conveyor (6) to start filling; Step 402, the bottom discharge scraper conveyor (6) discharges the gangue onto the multi-angle gangue throwing belt (7), and the multi-angle gangue throwing belt (7) throws the gangue into the flexible filling bag (12), and the gangue is layered and filled in the filling space by adjusting the belt speed and angle of the multi-angle gangue throwing belt (7), wherein, after each layer of gangue is filled, the grouting device (5) is used to inject the cementing agent into the flexible filling bag (12); wherein, during the process of layering and filling the gangue in the filling space, the self-standing time T of the filling body (4) is less than the next moving support period T of the filling hydraulic support (2) 充 . The self-standing time T of the filling body (4) is less than the next moving support period T of the filling hydraulic support (2) 周 .

5. The coal gangue precision adaptive filling method based on working face mine pressure regulation and control according to claim 1, characterized in that, In step 103, the filling hydraulic support (2) is 10 filling hydraulic supports (2) selected at equal intervals in the working face.

6. The coal gangue precision adaptive filling method based on working face mine pressure regulation according to claim 3, characterized in that, In step 304, if the optimal filling scheme is not obtained, a new filling position combination scheme is obtained again in step 302 until the optimal filling scheme is obtained.

7. The coal gangue precision adaptive filling method based on working face mine pressure regulation according to claim 4, characterized in that, The cementing agent is a cement water glass solution or a mixture of a water glass solution and a calcium chloride solution.

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