A Feedback Adjustment Method for Empty Area Filling Parameters Based on Probability Integral Method
By optimizing the paste filling parameters using the probability integral method, the problems of surface subsidence and high cost of filling materials after coal mining have been solved, achieving efficient, safe, and green coal mining.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA UNIV OF MINING & TECH
- Filing Date
- 2026-04-17
- Publication Date
- 2026-07-10
Smart Images
Figure CN122364635A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of green coal mining technology, and in particular relates to a feedback adjustment method for void filling parameters based on the probability integral method. Background Technology
[0002] Today, the concepts of green, low-carbon, and renewable resources have taken root in people's hearts. Under the background of the "dual carbon" strategy, it is particularly important to achieve green, safe, and efficient mining of coal resources. After coal resources are mined, a goaf of equal volume will be generated. At this time, the overlying strata will gradually be destroyed and subsided without the support of coal, eventually leading to large-scale subsidence of the surface, damaging surface buildings and the ecological environment, and seriously restricting the green and sustainable development of the coal industry.
[0003] To address the aforementioned issues, backfilling mining, as an effective technology for controlling the roof of goafs, has been widely applied in coal mines. Conventional backfilling techniques require the complete filling of the working space with paste or grout, resulting in excessively long bag-hanging time, filling time, and solidification time for the paste and grout, impacting work efficiency and easily leading to resource waste. Against this backdrop, how to reduce the time for paste and grouting processes while ensuring filling effectiveness and improving the utilization rate of the backfill material has become an urgent problem to be solved in green backfilling mining. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention proposes a feedback adjustment method for void filling parameters based on the probability integral method. This method aims to solve the problems of long processing time, high cost of filling materials, and insufficient gangue during filling mining in existing paste filling processes, while ensuring the effectiveness of filling mining in controlling surface subsidence.
[0005] To achieve the above objectives, the present invention provides a method for feedback adjustment of void filling parameters based on the probability integral method, comprising: Based on the distribution of surface protection objects and relevant regulations, determine the permissible surface deformation threshold; Based on the dip width of the filling area, the mining height and the preset filling rate, several interval filling schemes are designed, and the filling area width, void width and filling height in each scheme are determined. Among them, the filling area and void are arranged alternately. Based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated. The surface deformation parameters are compared with the allowable surface deformation threshold, and the alternative schemes that meet the threshold requirements are selected. Based on the alternative schemes, iterative optimization calculations are performed with the goal of reducing the filling rate to determine the minimum filling rate that satisfies the allowable surface deformation threshold, thereby obtaining optimized interval paste filling parameters.
[0006] Optionally, the surface protection objects include surface buildings / structures, water bodies, railways, and highways.
[0007] Optionally, based on the inclination width of the filling area, the mining height, and the preset filling rate, several interval filling schemes can be designed, including: The number of filling bodies and empty units are determined based on the filling area tendency width, the filling area width, and the empty area width. The filling height is determined based on the mining height and the preset filling rate; Based on the number of units and the filling height, several interval filling schemes are determined.
[0008] Optionally, the width of the empty zone is set according to the mining depth, and the width of the empty zone is not greater than 1 / 4 of the mining depth.
[0009] Optionally, the width of the filling area is greater than or equal to the width of the empty area.
[0010] Optionally, the surface deformation parameters include: horizontal deformation values. e m Inclined deformation value T m With curvature K m .
[0011] Optionally, based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated, including: ; in, fe The angle between the direction of maximum horizontal deformation and the OX axis; φT The angle between the direction of maximum tilt deformation and the OX axis; φk The angle between the direction of maximum curvature deformation and the OX axis; Wcm The maximum surface subsidence value under fully exploited conditions; Cx' , Cy' These are the subsidence distribution coefficients at the projection points of the point to be determined on the strike and dip main cross sections, respectively. ex , ey The horizontal deformation value of the point to be determined is superimposed on the projection of the main section along the strike and dip. Tx , Ty These are the superimposed tilt deformation values at the projection points of the point to be determined along the strike and dip of the main cross-section, respectively; Kx , Ky These are the curvature values of the point to be determined after superimposing along the strike and dip at the projection of the main section; Ux , Hey These represent the horizontal displacement values of the point to be determined at the projection point of the main section along the strike and dip, respectively.
[0012] Optionally, the paste filling material may include, by weight percentage: 35%~45% gangue, 40%~50% fly ash, 8%~12% cement, and 1%~3% quicklime, with a slurry concentration of 80%~85%, and 1%~3% quick-setting agent may be added as needed.
[0013] Compared with the prior art, the present invention has the following advantages and technical effects: This invention determines a reasonable deformation threshold by combining actual surface conditions, designs multiple interval filling schemes based on the working conditions of the coal mining area, accurately predicts surface subsidence using a probability integral method model, and selects schemes that meet the requirements. Then, by reducing the filling rate, a minimum reasonable value is determined, ultimately obtaining suitable interval paste filling parameters. This not only achieves coordinated control of surface deformation, filling time, and filling materials, but also effectively reduces the size of the filling body and process time while ensuring the safety and stability of surface buildings and transportation facilities, thus improving coal mining efficiency. Furthermore, by using mine solid waste such as gangue and fly ash as the main filling materials, it reduces the input cost of filling materials and alleviates the problem of insufficient gangue during filling mining in resource-scarce mines. It combines economic, safety, and ecological benefits, providing an efficient and feasible technical solution for green coal mining. Attached Figure Description
[0014] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart of a method for adjusting feedback parameters for empty area filling based on the probability integral method according to an embodiment of the present invention. Figure 2 This is a graph showing the relationship between the extreme value of surface movement and deformation and the length of the filling surface in an embodiment of the present invention with a non-empty area width of 40m. Figure 3 This is a graph showing the relationship between the extreme value of surface movement and deformation and the length of the filling surface in an embodiment of the present invention with a void width of 50m. Figure 4 This is a graph showing the relationship between the extreme value of surface movement and deformation and the length of the filling surface in an embodiment of the present invention, where the width of the empty area is 60m. Detailed Implementation
[0015] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0016] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.
[0017] This embodiment proposes a feedback adjustment method for void filling parameters based on the probability integral method, such as... Figure 1 As shown, the specific steps include: Based on the distribution of surface protection objects and relevant regulations, determine the permissible surface deformation threshold; Based on the dip width of the filling area, the mining height and the preset filling rate, several interval filling schemes are designed, and the filling area width, void width and filling height in each scheme are determined. Among them, the filling area and void are arranged alternately. Based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated. The surface deformation parameters are compared with the allowable surface deformation threshold, and the alternative schemes that meet the threshold requirements are selected. Based on the alternative schemes, iterative optimization calculations are performed with the goal of reducing the filling rate to determine the minimum filling rate that satisfies the allowable surface deformation threshold, thereby obtaining optimized interval paste filling parameters.
[0018] Specifically, (1) the surface deformation threshold for permissible coal mining is determined by combining the distribution of surface buildings, water bodies, railways and highways; (2) Based on the width of the filling area q mining height h Design several interval filling schemes and determine the width of the filling zone. m , width of empty area n With filling height h c The specific method is as follows: a. Filling is carried out only in the filling area, and the caving method is used to mine the void. The filling area and the void are arranged alternately. b. Based on some field practice in my country, in order to avoid the surface from exhibiting wavy subsidence, the width of the void should be ≤1 / 10 to 1 / 4 of the mining depth; in order to ensure the filling effect, the width of the filling area should be greater than or equal to the width of the void, and the ratio of the width of the void to the width of the filling area (n / m) should be 0 to 1. c. "Filling body + void area" unit u = q / ( m + n ); d. Based on field experience in backfilling mining, the filling rate is generally 90%, and the backfilling height is set accordingly. h c =0.9 h .
[0019] (3) The maximum horizontal deformation value was obtained by using the probability integral method model. e m Inclined deformation value T m With curvature K m Parameters such as these are used to determine whether the maximum surface deformation value meets the threshold requirements.
[0020] (4) After the surface deformation meets the requirements, reduce the filling rate and predict the surface subsidence again to determine the minimum filling rate for the surface deformation to meet the threshold requirements, so as to obtain the appropriate interval paste filling parameters.
[0021] Furthermore, the surface protection objects include surface buildings / structures, water bodies, railways, and highways.
[0022] Specifically, the surface deformation threshold mentioned in step (1) is determined based on the type of surface buildings, roads, etc., and with reference to standards such as the specifications for the retention of coal pillars and the specifications for coal mining in buildings, water bodies, railways and main shafts.
[0023] Furthermore, based on the dip width of the filling area, the mining height, and the preset filling rate, several interval filling schemes are designed, including: The number of filling bodies and empty units are determined based on the filling region's tendency width, the filling region's width, and the empty area's width. u = q / (m + n); Where u is the number of units, q is the width of the filling region, m is the width of the filling region, and n is the width of the empty region; The filling height is determined based on the mining height and the preset filling rate: h c =0.9 h ; in, h c Where h is the filling height, 0.9 is the preset filling rate; Based on the number of units and the filling height, several interval filling schemes are determined.
[0024] Specifically, firstly, several sets of results m and n that meet the conditions are determined by q, and then the number of units u is calculated by considering q and m and n together.
[0025] Furthermore, the width of the empty area is set according to the mining depth, and the width of the empty area is no greater than 1 / 4 of the mining depth.
[0026] Furthermore, the width of the filling area is greater than or equal to the width of the empty area.
[0027] Specifically, the parameters of the probability integral method model mainly include the sinking coefficient. q Main influencing angle tangent tanβ Horizontal shift coefficient b Inflection point movement distance S and the angle of propagation of the impact of mining f The method is determined based on the coal seam mining method, roof management method, overlying strata properties, number of repeated mining operations, and mining depth to thickness ratio. Furthermore, the surface deformation parameters include: horizontal deformation values. e m Inclined deformation value T m With curvature K m .
[0028] Furthermore, based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated as follows: ; in, fe The angle between the direction of maximum horizontal deformation and the OX axis; φT The angle between the direction of maximum tilt deformation and the OX axis; φk The angle between the direction of maximum curvature deformation and the OX axis; Wcm The maximum surface subsidence value under fully exploited conditions; Cx' , Cy' These are the subsidence distribution coefficients at the projection points of the point to be determined on the strike and dip main cross sections, respectively. ex , ey The horizontal deformation value of the point to be determined is superimposed on the projection of the main section along the strike and dip. Tx , Ty These are the superimposed tilt deformation values at the projection points of the point to be determined along the strike and dip of the main cross-section, respectively; Kx , Ky These are the curvature values of the point to be determined after superimposing along the strike and dip at the projection of the main section; Ux , Hey These represent the horizontal displacement values of the point to be determined at the projection point of the main section along the strike and dip, respectively.
[0029] Furthermore, the paste filling material includes, by mass percentage: 35%~45% gangue, 40%~50% fly ash, 8%~12% cement, and 1%~3% quicklime. The slurry concentration is 80%~85%, and 1%~3% quick-setting agent is added as needed. The strength can reach 7~10MPa.
[0030] The following is a detailed description of this embodiment: In a certain province, there is an area of coal seam under Laocheng in the mining area. The coal seam to be mined is No. 2 coal seam, with a bottom contour line of -650m, an average coal thickness of 2.95m, a coal seam dip angle of 2°, and a coal seam volume of 36.64 million tons. It is planned to use intermittent paste filling mining to recover the coal seam under Laocheng.
[0031] (1) Determine the allowable surface deformation threshold for coal mining based on the distribution of surface buildings, water bodies, railways and highways. According to the field survey results, the surface buildings affected by surface subsidence after mining in the filling area are mainly Beiguan Bridge, Chengguan Town Water Plant and Beifeng Well. According to the "Technical Specifications for Design and Construction of Highways in Mining Goaf Areas (JTG / T D31-03—2011)", the allowable deformation values of the foundation of bridges in the line project are shown in Table 1. The allowable deformation thresholds for Beiguan Bridge are: horizontal deformation 1.0 mm / m; tilt deformation 2.0 mm / m; curvature 0.15 mm / m. 2 The damage levels of brick-concrete structures are shown in Table 2. Considering the good building quality and strong deformation resistance in the area, the mining-induced deformation thresholds for the Chengguan Town Water Plant and the North Ventilation Shaft are designed as follows: horizontal deformation 2 mm / m; tilting deformation 3 mm / m; curvature deformation 0.2 mm / m. 2 .
[0032] Table 1 Table 2 (2) The design now selects a filling area in the filling mining area to arrange an intermittent filling working face. The dip length of the filling area is about 375m, the mining height is 2.95m, and the designed filling height is 2.66m. The specific intermittent paste filling mining scheme is as follows: Option 1: The width of the empty area is 40m, the width of the filling area is 40m, and there are 4 "filling body + empty area" units plus 1 empty area; Option 2: The empty area is 40m wide, the filling area is 60m wide, and there are 3 "filling body + empty area" units plus 1 empty area; Option 3: The empty area is 40m wide, the filling area is 80m wide, and there are 3 "filling body + empty area" units; Option 4: The width of the empty area is 50m, the width of the filling area is 50m, and there are 3 "filling body + empty area" units plus 1 empty area; Option 5: The empty area is 50m wide, the filling area is 80m wide, and there are 3 "filling body + empty area" units; Option 6: Void area width 50m, filling area width 100m, 2 "filling body + void area" units + 1 void area; Option 7: The width of the empty area is 60m, the width of the filling area is 60m, and there are 3 "filling body + empty area" units; Option 8: The width of the empty area is 60m, the width of the filling area is 80m, and there are 2 "filling body + empty area" units plus 1 empty area; Option 9: The empty area is 60m wide, the filling area is 100m wide, and there are 2 "filling body + empty area" units plus 1 empty area; Option 10: The empty area is 60m wide, the filling area is 120m wide, and there are 2 "filling body + empty area" units.
[0033] (3) Based on the surface movement observation data of the suburban coal mine, the predicted parameters were calculated by inversion using the existing observation data. At the same time, considering the surface movement and deformation characteristics of the thick loose layer, the predicted probability integral method parameters for surface subsidence of the suburban coal mine filling mining were selected as follows: subsidence coefficient: 1.2; main influence angle tangent: 1.8; horizontal movement coefficient: 0.35; inflection point offset distance: 0; mining influence propagation angle: 89°.
[0034] The extreme values of displacement and deformation of Beiguan Bridge, Chengguan Town Water Plant, and Beifeng Well under different schemes are as follows: ① Scheme 1 is shown in Table 3: Table 3 ② Option 2 is shown in Table 4: Table 4 ③ Option 3 is shown in Table 5: Table 5 ④ Option 4 is shown in Table 6: Table 6 Option 5 is shown in Table 7: Table 7 Option 6 is shown in Table 8: Table 8 ⑦ Option 7 is shown in Table 9: Table 9 Option 8 is shown in Table 10: Table 10 Option 9 is shown in Table 11: Table 11 Option 10 is shown in Table 12: Table 12 The results show that the extreme values of surface deformation in Schemes 1, 4, and 7 are all greater than the Class I standard protection level. The extreme values of surface deformation in other schemes, as well as the deformation at Beiguan Bridge, Chengguan Town Water Plant, and Beifeng Well within the influence range of surface subsidence, are all within the Class I standard. Beiguan Bridge is slightly affected by mining, while Chengguan Town Water Plant and Beifeng Well are unaffected due to their distance from the mining area. Among these, Scheme 6 has the lowest extreme value of surface movement deformation. The relationship between the extreme values of surface movement deformation with the length of the filling surface for different void widths is shown in the figure below. Figure 2-4 As shown in the analysis, when the width of the void is constant, the extreme values of surface subsidence, horizontal deformation, tilt deformation, and curvature deformation decrease with the increase of the filling face length. Therefore, in order to achieve better control over the ground surface, the filling face length should be increased as much as possible.
[0035] (4) Based on Scheme 6: 50m width of empty area, 100m width of filling area, and 90% filling rate, the filling rate is reduced, and the probability integral method is used to predict surface subsidence. The minimum filling rate at which surface deformation meets the threshold requirement is determined. The extreme values of surface movement deformation under different filling rates are as follows: ① When the filling rate is 90%, the surface movement and deformation technology is shown in Table 13: Table 13 ② When the filling rate is 85%, the surface movement and deformation technology is shown in Table 14: Table 14 ③ When the filling rate is 80%, the surface movement and deformation technology is shown in Table 15: Table 15 In summary, when the filling rate decreases to 80%, the predicted surface subsidence results indicate that the surface extreme value exceeds the threshold, and the damage level of surface buildings is Class II. Therefore, the parameters for the interval paste filling are determined as follows: void width 50m, filling zone width 100m, 2 "filled body + void" units + 1 void, and filling rate ≥85%.
[0036] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A method for feedback adjustment of void filling parameters based on probability integral method, characterized in that, include: Based on the distribution of surface protection objects and relevant regulations, determine the permissible surface deformation threshold; Based on the dip width of the filling area, the mining height and the preset filling rate, several interval filling schemes are designed, and the filling area width, void width and filling height in each scheme are determined. Among them, the filling area and void are arranged alternately. Based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated. The surface deformation parameters are compared with the allowable surface deformation threshold, and the alternative schemes that meet the threshold requirements are selected. Based on the alternative schemes, iterative optimization calculations are performed with the goal of reducing the filling rate to determine the minimum filling rate that satisfies the allowable surface deformation threshold, thereby obtaining optimized interval paste filling parameters.
2. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, The protected surface objects include surface buildings / structures, water bodies, railways, and highways.
3. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, Based on the dip width of the filling area, the mining height, and the preset filling rate, several interval filling schemes are designed, including: The number of filling bodies and empty units are determined based on the filling area tendency width, the filling area width, and the empty area width. The filling height is determined based on the mining height and the preset filling rate; Based on the number of units and the filling height, several interval filling schemes are determined.
4. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, The width of the empty area is set according to the mining depth, and the width of the empty area is no more than 1 / 4 of the mining depth.
5. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, The width of the filling area is greater than or equal to the width of the empty area.
6. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, The surface deformation parameters include: horizontal deformation value. ε m Inclined deformation value T m With curvature K m .
7. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 6, characterized in that, Based on the probability integral method model, the surface deformation parameters corresponding to each filling scheme are calculated as follows: ； in, φe The angle between the direction of maximum horizontal deformation and the OX axis; φT The angle between the direction of maximum tilt deformation and the OX axis; φk The angle between the direction of maximum curvature deformation and the OX axis; Wcm The maximum surface subsidence value under fully exploited conditions; Cx' , Cy' These are the subsidence distribution coefficients at the projection points of the point to be determined on the strike and dip main cross sections, respectively. εx , εy The horizontal deformation value of the point to be determined is superimposed on the projection of the main section along the strike and dip. Tx , Ty These are the superimposed tilt deformation values at the projection points of the point to be determined along the strike and dip of the main cross-section, respectively; Kx , Ky These are the curvature values of the point to be determined after superimposing along the strike and dip at the projection of the main section; Ux , Uy These represent the horizontal displacement values of the point to be determined at the projection point of the main section along the strike and dip, respectively.
8. The method for feedback adjustment of void filling parameters based on probability integral method according to claim 1, characterized in that, The paste filling material includes, by weight percentage: 35%~45% gangue, 40%~50% fly ash, 8%~12% cement, and 1%~3% quicklime. The slurry concentration is 80%~85%, and 1%~3% quick-setting agent is added as needed.