A method and system for inversion and control of separation layer grouting parameters

Abstract

The present invention belongs to the technical field of grouting and filling coal mining, and discloses a method and system for inversion and control of separation layer grouting parameters, determines the building protection level and the maximum allowable deformation value, brings the maximum allowable deformation value into the function expression of equivalent mining height, and takes the minimum value as the equivalent mining height; the limit separation layer space is equivalent to a three-dimensional geometric body and the volume of the three-dimensional geometric body is calculated, the mining influence propagation coefficient f is determined, and the compacted slurry volume is obtained from the mining space volume; the slurry volume injected into the separation layer is determined by the slurry injection ratio, and a three-dimensional geometric body mold with equal proportion is made after determining the similarity ratio; slurry is injected into the mold to simulate separation layer grouting, and a loading test is carried out to determine the slurry water separation rate and the slurry compaction rate; the slurry water separation rate and the slurry compaction rate are brought into the slurry volume formula, the slurry injection ratio and the grouting amount are calculated, and then the grouting subsidence reduction effect is evaluated. The present invention can protect surface buildings, achieve surface subsidence reduction, avoid excessive grouting, and effectively control the grouting cost.

Description

Technical Field

[0001] The invention belongs to the technical field of grouting filling coal mining, and in particular relates to a separation layer grouting parameter inversion and regulation method and system. Background Art

[0002] There are few patents on the inversion of the injection-production ratio of grouting for delamination. Chinese patent CN202311289335.5 discloses a comprehensive evaluation method for the effect of grouting and reducing subsidence in overburden delamination of coal mines. By analyzing and calculating the injection-production ratio, it is determined whether the delamination space is fully filled, and the grouting and reducing subsidence effect is evaluated according to the injection-production ratio. CN202211022327.X discloses a method for layout of coal mining-backfilling working face based on surface subsidence control requirements. Combining the advantages of backfilling mining and coordinated mining, the mine field is divided according to the surface subsidence control requirements of different regions, and the mining parameters are appropriately adjusted to reduce the damage of coal mining to the surface. CN202311136819.6 discloses a method for grouting and reducing subsidence in overburden multi-layer delamination in three soft and thick coal seams. Based on the composite beam theory and elastic wave plate theory, the grouting delamination layer position is identified, the safe thickness of the protective layer is determined, and the volume of the grouting filling space is obtained by constructing an equivalent model of the backfilling mining grouting space to improve the delamination grouting filling rate. CN202311205596.4 discloses a method for determining the grouting parameters for accurately protecting the delamination of the surface target in the mining area. The grouting parameters such as the grouting drilling depth, grouting pressure, and grouting drilling position are determined according to the geological mining conditions of the mining area, the deformation parameters of the overburden rock, and the surface protection, so as to remove the surface movement and deformation near the surface protection target. CN202310753247.X discloses a method for grouting and filling the overburden delamination. After comprehensively analyzing the surface deformation after coal mining, the damage to the surface buildings by the direct collapse method, the drilling exploration, etc., the appropriate grouting material is selected for filling, which improves the feasibility of filling the overburden delamination and the reliability of the key layer support after filling. CN202210135701.0 discloses a surface subsidence control grouting filling system based on the distribution law of abscission layer. The Gaussian mixture model and its parameters are determined according to the width of each lateral working area and the distribution depth of each abscission zone, and then these parameters are input into the established grouting filling amount prediction network to predict the filling amount and grouting rate of the next working area, so as to achieve accurate prediction of the total amount of grouting filling. The above patent mainly focuses on the grouting filling method, grouting effect evaluation and grouting parameter prediction. Although it involves the application of the injection-production ratio to evaluate the grouting subsidence reduction effect, the accuracy and reliability of the grouting subsidence reduction effect evaluation are insufficient, and no inversion method for the injection-production ratio of abscission grouting is proposed, which needs further research to fill the gap.

[0003] Through the above analysis, the problems and defects of the existing technology are: the existing technology is insufficient in accuracy and reliability in evaluating the effect of grouting to reduce settlement, and no inversion method for the injection-production ratio of delamination grouting is proposed. Summary of the invention

[0004] In order to overcome the problems existing in the related art, the disclosed embodiment of the present invention provides a method and system for inversion and control of separation layer grouting parameters.

[0005] The technical solution is as follows: a method for inversion and control of separation layer grouting parameters, comprising:

[0006] S1, determine the building protection level and the maximum allowable deformation value, substitute the maximum allowable deformation value into the derived functional expression of equivalent mining height, and take the minimum value as the equivalent mining height;

[0007] S2, according to the key layer theory, the evolution law of overburden stratum separation during coal seam mining is analyzed, and the data such as separation layer position, mining space size, separation layer development angle and sufficient mining angle are obtained by comprehensive geological conditions. The limit separation layer space is equivalent to a three-dimensional geometric body, and the volume of the three-dimensional geometric body is calculated according to the separation layer development angle and the sufficient mining angle, and the mining influence propagation coefficient f is determined. The volume of the compacted slurry is obtained through the mining space volume;

[0008] S3, determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and according to the limit abscission space, the compacted slurry is equivalent to a three-dimensional geometric body. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold and a loading test bench are made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly pressurized, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and the slurry compaction rate;

[0009] S4, put the obtained slurry water separation rate and slurry compaction rate into the calculation formula of slurry volume, calculate the parameters of slurry injection ratio and grouting amount; evaluate the grouting settlement reduction effect, adjust the grouting process according to the evaluation effect, and achieve organic coordination between grouting and surface settlement reduction.

[0010] In step S1, the maximum allowable deformation value is substituted into the derived functional expression of equivalent mining height, and the minimum value is taken as the equivalent mining height, which includes:

[0011] According to the protection level and damage level of buildings in the mining area, the horizontal deformation ε, inclination i and curvature K in the surface deformation value are determined, and the expression is:

[0012]

[0013] Where W(x) is the sinking curve, W cmis the maximum surface subsidence value, x is the distance along the advancing direction of the working face, r is the main influencing radius, λ is the parameter to be determined, i(x) is the inclination curve, e is a constant, K(x) is the curvature curve, U(x) is the horizontal movement curve, b is the horizontal movement coefficient, and ε(x) is the horizontal deformation curve;

[0014] W cm =H d qcosα

[0015]

[0016] λ=hx

[0017]

[0018] In the formula, H d is the equivalent mining coal seam height, H s is the buried depth of coal seam, q is the subsidence coefficient, α is the inclination angle of coal seam, β is the main influencing angle, and h is a constant;

[0019] Determine the equivalent mining height under the conditions of grouting filling in the separation layer along the advancing direction of the working face, the expression is:

[0020]

[0021] In the formula, H dε is the equivalent mining height obtained through horizontal deformation, H di is the equivalent mining height obtained by tilting, H dk is the equivalent mining height obtained by curvature;

[0022] Equivalent mining coal seam height H d for:

[0023] H d =min(H dε ,H di ,H dk ).

[0024] In step S2, the three-dimensional geometric body includes a trapezoidal body and a triangular body; under sufficient mining conditions, the compacted slurry in the separation layer is equivalent to a trapezoidal body; under insufficient mining conditions, the compacted slurry in the separation layer is equivalent to a triangular body.

[0025] In step S2, the step of converting the extreme separation space into a three-dimensional geometric body includes:

[0026] The limit separation space is equivalent to a trapezoidal body, and the volume of the slurry after compaction is calculated as:

[0027]

[0028] Where Vy is the simplified compacted slurry volume, L is the strike advance distance, H is i is the distance from the target layer to the coal seam, H j is the height of the detached space, β is the main influencing angle, W c is the width of the coal mining face;

[0029] At the key layer 1, the mining impact propagation coefficient is:

[0030]

[0031] Where f1 is the propagation coefficient of mining impact between the stratum space V1 and the mining space, V1 is the volume of the stratum space below the key layer 1, L1 is the strike advancement distance, H is the mining coal seam height, and H j1 is the height of the detached space V1;

[0032] At the key layer 2, the mining impact propagation coefficient is:

[0033]

[0034] Where f2 is the propagation coefficient of mining impact between the detached space V2 and the mining space, V2 is the volume of the detached space below the key layer 2, L2 is the strike advancement distance, and H j2 is the height of the detached space V2;

[0035] At the key layer i, the propagation coefficient of mining impact is:

[0036]

[0037] In the formula, f i V is the separation space i The mining impact transmission coefficient between the mining space and the mining space, V i is the volume of the separation space below the key layer i, L i H is the advancing distance, ji V is the separation space i Height;

[0038] At any critical layer l, the volume of the lower separation space is:

[0039] V l =fLW c H

[0040] f=(f1,f2,f3…)

[0041] Where V l is the volume of the target separation space, f is the separation space V l The mining impact propagation coefficient between the mining space and L is the strike advancement distance;

[0042] The mining impact propagation coefficient f,0 is determined by physical simulation, numerical simulation and field measurement methods. <f<1;

[0043] V y =fLW c (HH d ).

[0044] In step S2, the step of converting the extreme separation space into a three-dimensional geometric body further includes:

[0045] The limit separation space is equivalent to a triangle, and the calculation of the compacted slurry volume includes:

[0046]

[0047] Where V y is the simplified compacted slurry volume, W is the inclined advancement distance, H is j is the height of the detached space, L f is the length of the coal mining face; at the key layer 1, the mining impact propagation coefficient is:

[0048]

[0049] Where f1 is the propagation coefficient of mining impact between the separation space V1 and the mining space, V1 is the volume of the separation space below the key layer 1, H is the height of the mining coal seam, and H j1 is the height of the detached space V1, W1 is the inclination propulsion distance;

[0050] At the key layer 2, the mining impact propagation coefficient is:

[0051]

[0052] Where f2 is the propagation coefficient of mining impact between the delamination space V2 and the mining space, V2 is the volume of the delamination space below the key layer 2, and H j2 is the height of the detached space V2, W2 is the inclination propulsion distance;

[0053] At the key layer i, the propagation coefficient of mining impact is:

[0054]

[0055] In the formula, f i V is the separation space i The mining impact transmission coefficient between the mining space and the mining space, V i is the volume of the separation space below the key layer i, H ji V is the separation space i Height, W iTo advance the distance for the tendency;

[0056] At any critical layer l, the volume of the lower separation space is:

[0057] V l =fL f WH

[0058] f=(f1,f2,f3…)

[0059] Where V l is the volume of the target separation space, f is the separation space V l The mining impact transmission coefficient between the mining space and the mining space, L f is the length of the coal mining face, W is the inclination advancement distance;

[0060] The propagation coefficient f of mining impact is determined by physical simulation, numerical simulation and field measurement. <f<1;

[0061] V y =fL f W(HH d )

[0062] In step S3, the step of converting the extreme separation space into a three-dimensional geometric body includes:

[0063] The compacted slurry is equivalent to a trapezoidal body, and the slurry parameters are determined as follows:

[0064] V 注 =tV0=tLW c H

[0065] Where V 注 is the volume of injected slurry, V0 is the volume of the production space, t is the injection ratio, which is equal to the ratio of the volume of injected slurry to the volume of the production space, L is the strike advancement distance, and W c is the width of the coal mining face, and H is the height of the mined coal seam;

[0066] L 上 =nL

[0067]

[0068] L 宽 =nW c

[0069] h j =nH j

[0070] Where, L 上 is the upper boundary length of the trapezoidal mold, n is the similarity ratio, L 下 is the length of the lower boundary of the trapezoidal mold, H iis the distance from the target layer to the coal seam, H j is the height of the detached space, L 宽 is the mold width, h j is the mold height;

[0071] Slurry water separation rate K c The expression is:

[0072]

[0073] In the formula, K c is the slurry water separation rate, m s is the mass of precipitated water, m z is the mass of the slurry injected into the mold;

[0074] Slurry compaction rate K z The expression is:

[0075]

[0076] In the formula, K z is the slurry compaction rate; V z is the volume of the trapezoidal mold; V s is the volume of the trapezoidal mold after compression;

[0077] The dewatering rate and compaction rate of the trapezoidal mold are the same as those of the slurry injected into the abscission layer.

[0078] In step S3, the step of converting the extreme separation space into a three-dimensional geometric body further includes:

[0079] The compacted slurry is equivalent to a triangle, and the slurry parameters are determined as follows:

[0080] V 注 =tV0=tWL f H

[0081] Where V 注 is the volume of injected slurry, V0 is the volume of production space, t is the injection ratio, W is the distance of advancement, L f is the length of the coal mining face;

[0082] L 长 =nW

[0083] L 宽 =nL f

[0084] h j =nH j

[0085] In the formula, n is the similarity ratio, 0 <n<1;L 长is the length of the upper boundary of the triangular mold, L 宽 is the mold width, H j is the height of the detached space, h j is the mold height;

[0086]

[0087] In the formula, K c is the slurry water separation rate, m s is the mass of precipitated water, m z is the mass of the slurry injected into the mold;

[0088]

[0089] In the formula, K z is the slurry compaction rate, V fz is the volume of the triangular mold, V fs is the volume of the triangular mold after compression; the water separation rate and compaction rate of the triangular mold are the same as those of the slurry injected into the abscission layer.

[0090] In step S4, if the three-dimensional geometric body is a trapezoidal body, calculating the grouting parameters and grouting control includes:

[0091]

[0092] Where V 注 is the volume of injected slurry;

[0093]

[0094] Where t is the slurry injection ratio, ρ1 is the density before slurry injection, and ρ2 is the density after slurry compaction;

[0095] When advancing a unit distance along the direction of the coal seam, L = 1, the unit mining space volume W c H is equal to a constant. By changing the grouting volume, the proportion of injected slurry in the unit mining space volume is changed, and then the injection-production ratio is changed to realize the control of surface movement and deformation by delamination grouting. When the injection-production ratio does not reach the target requirement, the grouting volume is increased to improve the injection-production ratio. When the injection-production ratio just reaches the target requirement, the grouting volume is maintained to maintain the current injection-production ratio. When the injection-production ratio is much greater than the target requirement, the grouting volume is reduced to reduce the injection-production ratio.

[0096] In step S4, if the three-dimensional geometric body is a triangle, calculating the grouting parameters and grouting control includes:

[0097]

[0098] Where V 注 is the volume of injected slurry;

[0099]

[0100] Where, t is the slurry injection ratio;

[0101] When advancing a unit distance along the coal seam dip direction, W = 1, and the unit mining space volume L f H is equal to a constant. By changing the grouting volume, the proportion of injected slurry in the unit mining space volume is changed, and then the injection-production ratio is changed to realize the control of surface movement and deformation by delamination grouting. When the injection-production ratio does not reach the target requirement, the grouting volume is increased to improve the injection-production ratio. When the injection-production ratio just reaches the target requirement, the grouting volume is maintained to maintain the current injection-production ratio. When the injection-production ratio is much greater than the target requirement, the grouting volume is reduced to reduce the injection-production ratio.

[0102] Another object of the present invention is to provide a separation layer grouting parameter inversion and control system, which is used to control the separation layer grouting parameter inversion and control method, and the system includes:

[0103] The equivalent mining height solution module is used to determine the building protection level and the maximum allowable deformation value, and to bring the maximum allowable deformation value into the derived functional expression of the equivalent mining height, and take the minimum value as the equivalent mining height;

[0104] The module for calculating the volume of slurry after compaction is used to analyze the evolution law of overburden separation in coal seam mining according to the key layer theory, obtain data such as separation layer position, mining space size, separation layer development angle and sufficient mining angle based on comprehensive geological conditions, and convert the limit separation layer space into a three-dimensional geometric body. The volume of the three-dimensional geometric body is calculated according to the separation layer development angle and the sufficient mining angle, and the mining influence propagation coefficient f is determined. The volume of slurry after compaction is obtained through the mining space volume;

[0105] The slurry parameter determination module is used to determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and to convert the compacted slurry into a three-dimensional geometric body according to the limit abscission space. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold and a loading test bench are made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly compressed, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and the slurry compaction rate.

[0106] The grouting control module is used to input the obtained slurry water separation rate and slurry compaction rate into the calculation formula of the slurry volume, calculate the parameters of the slurry injection ratio and grouting amount; evaluate the grouting settlement reduction effect, adjust the grouting process according to the evaluation effect, and achieve organic coordination between grouting and surface settlement reduction.

[0107] Combining all the above technical solutions, the advantages and positive effects of the present invention are as follows:

[0108] 1. The present invention combines the probability integral method and the equivalent mining height model, and starts from the building protection level and the maximum allowable deformation value specified in the "Specifications for the Installation of Coal Pillars and Compressed Coal Mining in Buildings, Water Bodies, Railways and Main Shafts and Lanes", derives the functional expression of the equivalent mining height, and then calculates the equivalent mining height.

[0109] 2. According to the development law of overburden stratum separation, the present invention establishes the connection between the volume of non-mined coal seam and compacted slurry through the mining influence propagation coefficient f, and then calculates the volume of compacted slurry.

[0110] 3. The present invention uses a proportionally reduced triangular mold / trapezoidal mold, determines the similarity ratio according to the size of the loading test bench and the actual formation data, and then conducts a loading test to determine relevant parameters such as the water separation rate of the injected slurry and the slurry compaction rate.

[0111] 4. According to the inversion and control system for stratum grouting parameters of the present invention, starting from the surface movement deformation data, combined with the probability integral method, equivalent mining height, stratum development law, etc., the expressions of parameters such as slurry injection ratio and grouting volume are derived, and then the grouting process is controlled according to the evaluation of the grouting settlement reduction effect.

[0112] 5. The injection-production ratio inversion method of the present invention can not only protect surface buildings and reduce surface subsidence, but also avoid excessive grouting and effectively control grouting costs.

[0113] As auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects:

[0114] 1. After the technical solution of the present invention is transformed, after the surface movement deformation parameters are obtained, the grouting slurry volume and injection-production ratio at different mining stages can be predicted through the delamination grouting parameter inversion method of the present invention. By comparing with the grouting slurry volume and injection-production ratio, the grouting process is regulated according to the comparison results to ensure the grouting settlement reduction effect while avoiding excessive grouting, effectively reducing the grouting cost.

[0115] 2. The present invention discloses a method for inversion of separation layer grouting parameters. Firstly, starting from the building protection level and the maximum allowable deformation value specified in the "Specifications for the Retention and Compressed Coal Mining of Coal Pillars in Buildings, Water Bodies, Railways and Main Wells and Lanes", the function expression of the equivalent mining height is derived in combination with the probability integral method; then, the connection between the volume of the non-mined coal seam and the compacted slurry is established through the mining influence propagation coefficient f, and then the expression of the compacted slurry volume at any advancement position of the coal mining working face is derived; then, according to the limit separation layer space, the compacted slurry is equivalent to a three-dimensional geometric body, and after determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold is made, and then a loading test is carried out to simulate the slurry dehydration and compaction process, determine the slurry dehydration rate and the slurry compaction rate, and then calculate the grouting slurry volume and the injection-production ratio in combination with the compacted slurry volume expression, so as to realize the inversion of separation layer grouting parameters.

[0116] The present invention also proposes a system for regulating the delamination grouting process according to the inverted delamination grouting parameters, and realizes the regulation of the grouting process according to the inverted parameters and the grouting subsidence reduction effect.

[0117] 3. The present invention provides an inversion method for solving the stratum grouting parameters by reverse calculation and experiment starting from the ground surface movement deformation value, and combining the prediction results with the actual grouting situation to realize the regulation of the stratum grouting process.

[0118] 4. The previous technologies mainly focused on the control effect of surface subsidence after stratum grouting, rather than the stratum grouting process and the solution of grouting parameters. The present invention proposes a method and system for reverse solution of stratum grouting parameters. Starting from the surface movement deformation value, the stratum grouting parameters are reversely solved through a series of calculations and experiments, and the prediction results and actual grouting conditions are combined to realize the regulation of the grouting process. BRIEF DESCRIPTION OF THE DRAWINGS

[0119] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the description, serve to explain the principles of the present disclosure;

[0120] Figure 1 It is a flow chart of the separation layer grouting parameter inversion and control method provided by an embodiment of the present invention;

[0121] Figure 2 The present invention provides an embodiment of the present invention, which provides a schematic diagram of the development of the delamination space in which the extreme delamination space is equivalent to a trapezoidal body;

[0122] Figure 3 It is a simplified schematic diagram of the delamination space provided by an embodiment of the present invention, in which the extreme delamination space is equivalent to a trapezoidal body;

[0123] Figure 4The present invention provides an embodiment of the present invention, which provides a schematic diagram of the development of the desorption space in which the extreme desorption space is equivalent to a triangle;

[0124] Figure 5 This is a simplified schematic diagram of the delamination space provided by an embodiment of the present invention, in which the extreme delamination space is equivalent to a triangle;

[0125] Figure 6 is a schematic diagram of a trapezoidal mold provided by an embodiment of the present invention;

[0126] Figure 7 It is a schematic diagram of a loading test bench provided by an embodiment of the present invention in which the compacted slurry is equivalent to a trapezoidal body;

[0127] Figure 8 is a schematic diagram of a triangular mold provided by an embodiment of the present invention;

[0128] Fig. 9 It is a schematic diagram of a loading test bench provided by an embodiment of the present invention in which the compacted slurry is equivalent to a triangle;

[0129] Fig.10 It is a schematic diagram of a grouting control system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0130] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0131] The innovation of the present invention is:

[0132] 1. The present invention discloses a method for inversion of separation layer grouting parameters. Firstly, starting from the building protection level and the maximum allowable deformation value specified in the "Specifications for the Retention and Compressed Coal Mining of Coal Pillars in Buildings, Water Bodies, Railways and Main Wells and Lanes", the function expression of the equivalent mining height is derived in combination with the probability integral method; then, the connection between the volume of the non-mined coal seam and the compacted slurry is established through the mining influence propagation coefficient f, and then the expression of the compacted slurry volume at any advancement position of the coal mining working face is derived; then, according to the limit separation layer space, the compacted slurry is equivalent to a three-dimensional geometric body, and after determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold is made, and then a loading test is carried out to simulate the slurry dehydration and compaction process, determine the slurry dehydration rate and the slurry compaction rate, and then calculate the grouting slurry volume and the injection-production ratio in combination with the compacted slurry volume expression, so as to realize the inversion of separation layer grouting parameters.

[0133] 2. The present invention proposes a system for regulating the delamination grouting process according to the inverted delamination grouting parameters, and realizes the regulation of the grouting process according to the inversion parameters and the grouting subsidence reduction effect.

[0134] Examples, such as Figure 1 As shown, the method for inversion and control of separation layer grouting parameters provided by the embodiment of the present invention includes the following steps:

[0135] S1, determine the building protection level and the maximum allowable deformation value, substitute the maximum allowable deformation value into the derived functional expression of equivalent mining height, and take the minimum value as the equivalent mining height; determine the building protection level and the maximum allowable deformation value according to the provisions of the "Specifications for Coal Pillar Retention and Coal Compressing Mining for Buildings, Water Bodies, Railways and Main Wells and Lanes";

[0136] S2, according to the key layer theory, the evolution law of overburden stratum separation during coal seam mining is analyzed, and the stratum position, mining space size, stratum separation development angle and sufficient mining angle are obtained based on the geological conditions. The limit stratum separation space is equivalent to a three-dimensional geometric body, and the volume of the three-dimensional geometric body is calculated according to the stratum separation development angle and the sufficient mining angle, and the mining influence propagation coefficient f is determined. The volume of the compacted slurry is obtained through the mining space volume;

[0137] S3, determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and according to the limit abscission space, the compacted slurry is equivalent to a three-dimensional geometric body. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold and a loading test bench are made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly pressurized, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and the slurry compaction rate;

[0138] S4, put the obtained slurry water separation rate and slurry compaction rate into the calculation formula of slurry volume, calculate the parameters of slurry injection ratio and grouting amount; evaluate the grouting settlement reduction effect, adjust the grouting process according to the evaluation effect, and achieve organic coordination between grouting and surface settlement reduction.

[0139] In step S1, solving the equivalent mining height in the embodiment of the present invention specifically includes:

[0140] Determine the surface deformation value by referring to the mineral building protection level and building damage level specified in the "Specifications for Coal Pillar Retention and Compressed Coal Mining in Buildings, Water Bodies, Railways and Main Shafts and Tunnels": determine the horizontal deformation ε, inclination i and curvature K in the surface deformation value.

[0141] Table 1 Classification of protection levels of buildings in mining areas

[0142]

[0143]

[0144] Where W(x) is the sinking curve, W cm is the maximum surface subsidence value, in mm; x is the distance along the advancing direction of the working face, in m; r is the main influencing radius, in m; λ is an undetermined parameter, i(x) is the inclination curve, e is a constant, K(x) is the curvature curve, U(x) is the horizontal movement curve, b is the horizontal movement coefficient, and ε(x) is the horizontal deformation curve.

[0145] W cm =H d qcosα(2)

[0146]

[0147] λ=hx(4)

[0148]

[0149] In the formula, H d is the equivalent mining coal seam height, in m; H s is the coal seam burial depth, in m; q is the subsidence coefficient, α is the coal seam inclination, in °; β is the main influencing angle, in °; h is a constant.

[0150] Substituting equations (2) to (5) into equation (1), we can obtain the equivalent mining height expression under the conditions of grouting filling along the working face advancement direction (dip direction):

[0151]

[0152] In the formula, H dε is the equivalent mining height obtained from horizontal deformation, in m; H di is the equivalent mining height obtained by inclination, in m; H dk is the equivalent mining height obtained from the curvature, in m.

[0153] Equivalent mining coal seam height H d for:

[0154] H d =min(H dε ,H di ,H dk )(7)

[0155] In step S2, if the limit separation space is equivalent to a trapezoidal body, the method for calculating the volume of the compacted slurry in the embodiment of the present invention specifically includes:

[0156] Combined with geological data, the development law of overburden strata is analyzed to obtain parameters such as stratum position, mining space size, stratum development angle, and full mining angle. The schematic diagram of stratum space development is shown in the figure. Figure 2 As shown. Under full mining conditions, the compacted slurry in the separation layer is approximately a trapezoidal body. During the separation layer grouting process, the high-pressure slurry will have a certain expansion effect on the separation layer, but the separation layer expansion is not significant. Therefore, the present invention does not consider the expansion effect of the grouting pressure on the separation layer. The simplified separation layer space schematic diagram is as follows Figure 3 shown.

[0157]

[0158] Where V y is the simplified compacted slurry volume in m 3 ; L is the strike advance distance, in m; H i is the distance from the target layer to the coal seam, in m; H j is the height of the detached space, in m; β is the main influence angle, in °; W c is the width of the coal mining face, in meters.

[0159] At the key layer 1, the mining impact propagation coefficient is:

[0160]

[0161] Where f1 is the propagation coefficient of mining impact between the delamination space V1 and the mining space; V1 is the volume of the delamination space below the key layer 1, in m 3 ; L1 is the strike advance distance, in m; H is the height of the mined coal seam, in m; H j1 is the height of the detached space V1, in meters.

[0162] At the key layer 2, the mining impact propagation coefficient is:

[0163]

[0164] Where f2 is the propagation coefficient of mining impact between the delamination space V2 and the mining space; V2 is the volume of the delamination space below the key layer 2, in m 3 ; L2 is the strike advance distance, in m; H j2 is the height of the detached space V2, in meters.

[0165] At the key layer i, the propagation coefficient of mining impact is:

[0166]

[0167] In the formula, f i V is the separation space iThe mining impact transmission coefficient between the mining space and the mining space; V i is the volume of the separation space below the key layer i, in m 3 ; L i is the strike advance distance, in m; H ji V is the separation space i The height in meters.

[0168] At any critical layer l, the volume of the lower separation space is:

[0169] V l =fLW c H(12)

[0170] f=(f1,f2,f3…)(13)

[0171] Where V l is the volume of the target separation space, in m 3 ; f is the separation space V l The propagation coefficient of mining impact between the mining space; L is the strike advancement distance, in m; W is the width of the coal mining face, in m.

[0172] The mining impact transmission coefficient f is determined by physical simulation, numerical simulation, field measurement and other methods according to formula (8) to formula (13). It can be seen from formula (12) and formula (13) that 0 <f<1。

[0173] V y =fLW c (HH d )(14)

[0174] Where V y is the volume of compacted slurry, in m 3 .

[0175] In step S2, if the extreme separation space is equivalent to a triangle, the method for calculating the volume of the compacted slurry in the embodiment of the present invention specifically includes:

[0176] Combined with geological data, the development law of overburden strata is analyzed to obtain parameters such as stratum position, stratum development angle, full mining angle, and mining space size. The schematic diagram of stratum space development is shown in the figure. Figure 4 As shown. Under the condition of insufficient mining, the compacted slurry in the separation layer is approximately triangular. During the separation layer grouting process, the high-pressure slurry will have a certain expansion effect on the separation layer, but the separation layer expansion is not significant. Therefore, the present invention does not consider the expansion effect of the grouting pressure on the separation layer. The simplified separation layer space schematic diagram is as follows Figure 5 shown.

[0177]

[0178] Where V y is the simplified compacted slurry volume in m 3 ; W is the inclination advance distance, in m; H j is the height of the detached space, in meters; L f It is the length of coal mining face, in meters.

[0179] At the key layer 1, the mining impact propagation coefficient is:

[0180]

[0181] Where f1 is the propagation coefficient of mining impact between the delamination space V1 and the mining space; V1 is the volume of the delamination space below the key layer 1, in m 3 ; H is the height of the mining coal seam, in m; H j1 is the height of the detached space V1, in meters; W1 is the inclination advancement distance, in meters.

[0182] At the key layer 2, the mining impact propagation coefficient is:

[0183]

[0184] Where f2 is the propagation coefficient of mining impact between the delamination space V2 and the mining space; V2 is the volume of the delamination space below the key layer 2, in m 3 ;H j2 is the height of the detached space V2, in meters; W2 is the inclination advancement distance, in meters.

[0185] At the key layer i, the propagation coefficient of mining impact is:

[0186]

[0187] In the formula, f i V is the separation space i The mining impact transmission coefficient between the mining space and the mining space; V i is the volume of the separation space below the key layer i, in m 3 ;H ji V is the separation space i Height, in m; W i is the inclination advancement distance, in meters.

[0188] By analogy, at any key layer l, the volume of the lower detached space is:

[0189] V l =fWL f H(19)

[0190] f=(f1,f2,f3…)(20)

[0191] Where V l is the volume of the target separation space, in m 3 ; f is the separation space V l The mining impact transmission coefficient between the mining space and the mining space; L f is the length of the coal mining face, in meters; W is the inclination advancement distance, in meters.

[0192] The mining impact transmission coefficient f is determined by physical simulation, numerical simulation, field measurement and other methods according to formula (15) to formula (20). It can be seen from formula (19) and formula (20) that 0 <f<1。

[0193] V y =fL f W(HH d )(twenty one)

[0194] Where V y is the volume of compacted slurry, in m 3 .

[0195] In step S3, if the compacted slurry is equivalent to a trapezoidal body, the slurry parameters determined in the embodiment of the present invention specifically include:

[0196] V 注 =tV0=tLW c H(22)

[0197] Where V 注 is the volume of injected slurry, in m 3 ; V0 is the mining space volume, unit is m 3 ; t is the injection ratio, which is equal to the ratio of the injected slurry volume to the production space volume, in %; L is the strike advancement distance, in m; W c is the width of the coal mining face, in meters; H is the height of the mined coal seam, in meters.

[0198] L 上 =nL(23)

[0199]

[0200] L 宽 =nW c (25)

[0201] h j =nH j (26)

[0202] Where, L 上 is the length of the upper boundary of the trapezoidal mold, in cm; n is the similarity ratio, L下 H is the length of the lower boundary of the trapezoidal mold, in cm; i is the distance from the target layer to the coal seam, in cm; H j is the height of the detached space, in m; β is the main influence angle, in °; L 宽 h is the mold width in cm; j is the mold height in cm.

[0203] Trapezoidal mold schematic diagram Figure 6 The schematic diagram of the loading test bench is shown in Figure 7 shown.

[0204] Slurry water separation rate K c The expression is:

[0205]

[0206] In the formula, K c is the slurry dewatering rate, slurry dewatering rate K c Affected by grouting materials, proportions and applied loads, unit: %; m s is the mass of precipitated water, in g; m z is the mass of slurry injected into the mold, in g.

[0207] Slurry compaction rate K z The expression is:

[0208]

[0209] In the formula, K z V is the slurry compaction rate, which is affected by grouting materials, proportions and applied loads, and the unit is %; z is the volume of the trapezoidal mold, equal to the volume of the injected slurry, in cm 3 ; V s is the volume of the trapezoidal mold after compression, in cm 3 .

[0210] The dewatering rate and compaction rate of the trapezoidal mold are the same as those of the slurry injected into the abscission layer.

[0211] In step S3, if the compacted slurry is equivalent to a triangle, the slurry parameters determined in the embodiment of the present invention specifically include:

[0212] V 注 =tV0=tWL f H(29)

[0213] Where V 注 is the volume of injected slurry, in m 3 ; V0 is the mining space volume, unit is m3 ; t is the injection ratio, which is equal to the ratio of the injected slurry volume to the production space volume, in %.

[0214] L 长 =nW(30)

[0215] L 宽 =nL f (31)

[0216] h j =nH j (32)

[0217] In the formula, n is the similarity ratio, 0 <n<1;L 长 L is the length of the upper boundary of the triangular mold, in cm; 宽 H is the mold width in cm; j is the height of the detached space, in meters; h j is the mold height in cm.

[0218]

[0219] In the formula, K c is the slurry water separation rate, K c Affected by grouting materials, proportions and applied loads, unit: %; m s is the mass of precipitated water, in g; m z is the mass of slurry injected into the mold, in g.

[0220]

[0221] In the formula, K z V is the slurry compaction rate, which is affected by grouting materials, proportions and applied loads, and the unit is %; fz is the volume of the triangular mold, equal to the volume of the injected slurry, in cm 3 ; V fs is the volume of the triangular mold after compression, in cm 3 .

[0222] Since the triangular mold is manufactured by reducing the size in proportion to a similar ratio, the water separation rate and compaction rate of the triangular mold are the same as those of the slurry injected into the abscission layer.

[0223] In step S4, if the three-dimensional geometric body is a trapezoidal body, the calculation of grouting parameters and grouting control in the embodiment of the present invention specifically include:

[0224]

[0225] Where V 注 is the volume of injected slurry, in m3 .

[0226]

[0227] Where t is the slurry injection ratio, in %; ρ1 is the density before slurry injection, in Kg / m 3 ; ρ2 is the density after grout compaction, unit is Kg / m 3 .

[0228] When advancing a unit distance (L=1) along the direction of the coal seam, the unit mining space volume W c H is equal to a constant. At this time, the proportion of injected slurry in the unit mining space volume can be changed by changing the grouting volume, thereby changing the injection-production ratio, and realizing the precise control of surface movement and deformation by separation grouting. When the injection-production ratio does not meet the target requirements, increase the grouting volume to improve the injection-production ratio; when the injection-production ratio just meets the target requirements, maintain the grouting volume to maintain the current injection-production ratio; when the injection-production ratio is much greater than the target requirements, reduce the grouting volume to reduce the injection-production ratio.

[0229] In step S4, if the three-dimensional geometric body is a triangle, the calculation of grouting parameters and grouting control in the embodiment of the present invention specifically include:

[0230]

[0231] Where V 注 is the volume of injected slurry, in m 3 .

[0232]

[0233] Wherein, t is the slurry injection ratio, in %.

[0234] When advancing a unit distance (W = 1) along the coal seam dip direction, the unit mining space volume L f H is equal to a constant. At this time, the proportion of injected slurry in the unit mining space volume can be changed by changing the grouting volume, thereby changing the injection-production ratio, and realizing the precise control of surface movement and deformation by separation grouting. When the injection-production ratio does not meet the target requirements, increase the grouting volume to improve the injection-production ratio; when the injection-production ratio just meets the target requirements, maintain the grouting volume to maintain the current injection-production ratio; when the injection-production ratio is much greater than the target requirements, reduce the grouting volume to reduce the injection-production ratio.

[0235] like Fig.10 As shown, the grouting control system provided by the embodiment of the present invention includes:

[0236] The equivalent mining height solution module is used to determine the building protection level and the maximum allowable deformation value. The maximum allowable deformation value is substituted into the function expression for deriving the equivalent mining height, and the minimum value is taken as the equivalent mining height.

[0237] The module for calculating the volume of slurry after compaction is used to analyze the evolution law of overburden separation in coal seam mining according to the key layer theory, obtain data such as separation layer position, mining space size, separation layer development angle and sufficient mining angle based on comprehensive geological conditions, and equate the limit separation layer space to a solid geometric body and calculate the volume of the solid geometric body, determine the mining influence propagation coefficient f, and obtain the volume of slurry after compaction from the mining space volume;

[0238] The slurry parameter determination module is used to determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and to convert the compacted slurry into a three-dimensional geometric body according to the limit abscission space. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold is made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly compressed, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and slurry compaction rate.

[0239] The grouting control module is used to input the obtained slurry water separation rate and slurry compaction rate into the slurry volume calculation formula to calculate the parameters of slurry injection ratio and grouting amount; then evaluate the grouting settlement reduction effect, adjust the grouting process according to the evaluation effect, and achieve organic coordination between grouting and surface settlement reduction.

[0240] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0241] Since the information interaction, execution process, etc. between the above-mentioned devices / units are based on the same concept as the method embodiment of the present invention, their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0242] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated in one processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment.

[0243] According to an embodiment of the present application, the present invention also provides a computer device, which includes: at least one processor, a memory, and a computer program stored in the memory and executable on the at least one processor, wherein the processor implements the steps in any of the above-mentioned method embodiments when executing the computer program.

[0244] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

[0245] An embodiment of the present invention further provides an information data processing terminal, which, when executed on an electronic device, provides a user input interface to implement the steps in the above method embodiments. The information data processing terminal is not limited to mobile phones, computers, and switches.

[0246] An embodiment of the present invention further provides a server, which is used to provide a user input interface to implement the steps in the above method embodiments when executed on an electronic device.

[0247] An embodiment of the present invention further provides a computer program product. When the computer program product is run on an electronic device, the electronic device can implement the steps in the above-mentioned method embodiments when executing the computer program product.

[0248] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the camera / terminal device, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. For example, a USB flash drive, a mobile hard disk, a disk or an optical disk.

[0249] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0250] In order to further demonstrate the positive effects of the above embodiment, the present invention conducts the following experiments based on the above technical solution.

[0251] Assume that the length of a certain separation layer grouting coal mining working face is L, the coal seam height is H, and the coal seam burial depth is H s , advance to W c At this time, the ground surface inclination is A, the ground surface has reached full mining, and the slurry Qm has been injected 3 , then the equivalent mining coal seam height is:

[0252]

[0253] The volume of the compacted slurry is:

[0254]

[0255] The slurry water separation rate K is obtained from the loading test c , slurry compaction rate K z , the density of slurry before injection ρ1, the density of slurry after compaction ρ2, the volume of injected slurry and injection-production ratio are:

[0256]

[0257]

[0258] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for inversion and control of separation layer grouting parameters, characterized in that: The method includes: S1, determine the building protection level and the maximum allowable deformation value, substitute the maximum allowable deformation value into the derived functional expression of equivalent mining height, and take the minimum value as the equivalent mining height; S2, according to the key layer theory, the evolution law of overburden stratum separation during coal seam mining is analyzed, and the stratum position, mining space size, stratum separation development angle and sufficient mining angle are obtained based on the geological conditions. The limit stratum separation space is equivalent to a three-dimensional geometric body, and the volume of the three-dimensional geometric body is calculated according to the stratum separation development angle and the sufficient mining angle, and the mining influence propagation coefficient f is determined. The volume of the compacted slurry is obtained through the mining space volume; S3, determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and according to the limit abscission space, the compacted slurry is equivalent to a three-dimensional geometric body. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold and a loading test bench are made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly pressurized, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and the slurry compaction rate; S4, the obtained slurry water separation rate and slurry compaction rate are brought into the calculation formula of slurry volume, and the parameters of slurry injection ratio and grouting amount are calculated; the grouting settlement reduction effect is evaluated, and the grouting process is adjusted according to the evaluation effect to achieve organic coordination between grouting and surface settlement reduction; In step S1, the maximum allowable deformation value is substituted into the derived functional expression of equivalent mining height, and the minimum value is taken as the equivalent mining height, which includes: According to the protection level and damage level of buildings in the mining area, the horizontal deformation ε, inclination i and curvature K in the surface deformation value are determined, and the expression is: Where W(x) is the sinking curve, W cm is the maximum surface subsidence value, x is the distance along the advancing direction of the working face, r is the main influencing radius, λ is the parameter to be determined, i(x) is the inclination curve, e is a constant, K(x) is the curvature curve, U(x) is the horizontal movement curve, b is the horizontal movement coefficient, and ε(x) is the horizontal deformation curve; W cm =H d qcoα λ=hx In the formula, H d is the equivalent mining coal seam height, H s is the buried depth of coal seam, q is the subsidence coefficient, α is the inclination angle of coal seam, β is the main influencing angle, and h is a constant; Determine the equivalent mining height under the conditions of grouting filling in the separation layer along the advancing direction of the working face. The expression is: In the formula, H dε is the equivalent mining height obtained through horizontal deformation, H di is the equivalent mining height obtained by tilting, H dk is the equivalent mining height obtained by curvature; Equivalent mining coal seam height H d for: H d =min(H dε ,H di ,H dk ) In step S2, the three-dimensional geometric body includes a trapezoidal body and a triangular body; under sufficient mining conditions, the compacted slurry in the separation layer is equivalent to a trapezoidal body; under insufficient mining conditions, the compacted slurry in the separation layer is equivalent to a triangular body.

2. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S2, the step of converting the extreme separation space into a three-dimensional geometric body includes: The limit separation space is equivalent to a trapezoidal body, and the volume of the slurry after compaction is calculated as: Where V y is the simplified compacted slurry volume, L is the strike advance distance, H is i is the distance from the target layer to the coal seam, H j is the height of the detached space, β is the main influencing angle, W c is the width of the coal mining face; At the key layer 1, the mining impact propagation coefficient is: Where f1 is the propagation coefficient of mining impact between the stratum space V1 and the mining space, V1 is the volume of the stratum space below the key layer 1, L1 is the strike advancement distance, H is the mining coal seam height, and H j1 is the height of the detached space V1; At the key layer 2, the mining impact propagation coefficient is: Where f2 is the propagation coefficient of mining impact between the detached space V2 and the mining space, V2 is the volume of the detached space below the key layer 2, L2 is the strike advancement distance, and H j2 is the height of the detached space V2; At the key layer i, the propagation coefficient of mining impact is: In the formula, f i V is the separation space i The mining impact transmission coefficient between the mining space and the mining space, V i is the volume of the separation space below the key layer i, L i H is the advancing distance, ji V is the separation space i Height; At any critical layer l, the volume of the lower separation space is: V l =fLW c H f=(f1,f2,f3…) Where V l is the volume of the target separation space, f is the separation space V l The mining impact propagation coefficient between the mining space and L is the strike advancement distance; The mining impact propagation coefficient f,0 is determined by physical simulation, numerical simulation and field measurement methods. <f<1; V y =fLW c (H-H d )。 3. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S2, the step of converting the extreme separation space into a three-dimensional geometric body further includes: The limit separation space is equivalent to a triangle, and the calculation of the compacted slurry volume includes: Where V y is the simplified compacted slurry volume, W is the inclined advancement distance, H is j is the height of the detached space, L f is the length of the coal mining face; At the key layer 1, the mining impact propagation coefficient is: Where f1 is the propagation coefficient of mining impact between the separation space V1 and the mining space, V1 is the volume of the separation space below the key layer 1, H is the height of the mining coal seam, and H j1 is the height of the detached space V1, W1 is the inclination propulsion distance; At the key layer 2, the mining impact propagation coefficient is: Where f2 is the propagation coefficient of mining impact between the delamination space V2 and the mining space, V2 is the volume of the delamination space below the key layer 2, and H j2 is the height of the detached space V2, W2 is the inclination propulsion distance; At the key layer i, the propagation coefficient of mining impact is: In the formula, f i V is the separation space i The mining impact transmission coefficient between the mining space and the mining space, V i is the volume of the separation space below the key layer i, H ji V is the separation space i Height, W i To advance the distance for the tendency; At any critical layer l, the volume of the lower separation space is: V l =fL f WH f=(f1,f2,f3…) Where V l is the volume of the target separation space, f is the separation space V l The mining impact transmission coefficient between the mining space and the mining space, L f is the length of the coal mining face, W is the inclination advancement distance; The mining impact transmission coefficient f is determined by physical simulation, numerical simulation and field measurement. <f<1; V y =fL f W(H-H d )。 4. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S3, the step of converting the extreme separation space into a three-dimensional geometric body includes: The compacted slurry is equivalent to a trapezoidal body, and the slurry parameters are determined as follows: V 注 =tV0=tLW c H Where V 注 is the volume of injected slurry, V0 is the volume of the production space, t is the injection ratio, which is equal to the ratio of the volume of injected slurry to the volume of the production space, L is the strike advancement distance, and W c is the width of the coal mining face, and H is the height of the mined coal seam; L 上 =nL L 宽 =nW c h j =nH j Where, L 上 is the upper boundary length of the trapezoidal mold, n is the similarity ratio, L 下 is the length of the lower boundary of the trapezoidal mold, H i is the distance from the target layer to the coal seam, H j is the height of the detached space, β is the main influencing angle, L 宽 is the mold width, h j is the mold height; Slurry water separation rate K c The expression is: In the formula, K c is the slurry water separation rate, m s is the mass of precipitated water, m z is the mass of the slurry injected into the mold; Slurry compaction rate K z The expression is: In the formula, K z is the slurry compaction rate; V z is the volume of the trapezoidal mold; V s is the volume of the trapezoidal mold after compression; The dewatering rate and compaction rate of the trapezoidal mold are the same as those of the slurry injected into the abscission layer.

5. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S3, the step of converting the extreme separation space into a three-dimensional geometric body further includes: The compacted slurry is equivalent to a triangle, and the slurry parameters are determined as follows: V 注 =tV0=tWL f H Where V 注 is the volume of injected slurry, V0 is the volume of production space, t is the injection ratio, W is the distance of advancement, L f is the length of the coal mining face, H is the height of the mined coal seam; L 长 =nW L 宽 =nL f h j =nH j In the formula, n is the similarity ratio, 0 <n<1;L 长 is the length of the upper boundary of the triangular mold, L 宽 is the mold width, H j is the height of the detached space, h j is the mold height; In the formula, K c is the slurry water separation rate, m s is the mass of precipitated water, m z is the mass of the slurry injected into the mold; In the formula, K z is the slurry compaction rate, V fz is the volume of the triangular mold, V fs is the volume of the triangular mold after compression; the water separation rate and compaction rate of the triangular mold are the same as those of the slurry injected into the abscission layer.

6. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S4, if the three-dimensional geometric body is a trapezoidal body, calculating the grouting parameters and grouting control includes: Where V 注 is the volume of injected slurry, L is the distance of advancement, H is i is the distance from the target layer to the coal seam, H j is the height of the detached space, β is the main influencing angle, W c is the width of the coal mining face, K c is the slurry water separation rate, K z is the slurry compaction rate, H is the height of the mined coal seam; Where t is the slurry injection ratio, ρ1 is the density before slurry injection, and ρ2 is the density after slurry compaction; When advancing a unit distance along the direction of the coal seam, L = 1, the unit mining space volume W c H is equal to a constant. By changing the grouting volume, the proportion of injected slurry in the unit mining space volume is changed, and then the injection-production ratio is changed to realize the control of surface movement and deformation by delamination grouting. When the injection-production ratio does not reach the target requirement, the grouting volume is increased to improve the injection-production ratio. When the injection-production ratio just reaches the target requirement, the grouting volume is maintained to maintain the current injection-production ratio. When the injection-production ratio is much greater than the target requirement, the grouting volume is reduced to reduce the injection-production ratio.

7. The method for inversion and control of separation layer grouting parameters according to claim 1, characterized in that: In step S4, if the three-dimensional geometric body is a triangle, calculating the grouting parameters and grouting control includes: Where V 注 is the volume of injected slurry, W is the distance of advancement, H is j is the height of the detached space, L f is the length of the coal mining face, K c is the slurry water separation rate, K z is the slurry compaction rate; Where, t is the slurry injection ratio, H is the height of the mined coal seam, ρ1 is the density before slurry injection, and ρ2 is the density after slurry compaction; When advancing a unit distance along the coal seam dip direction, W = 1, and the unit mining space volume L f H is equal to a constant. By changing the grouting volume, the proportion of injected slurry in the unit mining space volume is changed, and then the injection-production ratio is changed to realize the control of surface movement and deformation by delamination grouting. When the injection-production ratio does not reach the target requirement, the grouting volume is increased to improve the injection-production ratio. When the injection-production ratio just reaches the target requirement, the grouting volume is maintained to maintain the current injection-production ratio. When the injection-production ratio is much greater than the target requirement, the grouting volume is reduced to reduce the injection-production ratio.

8. A separation layer grouting parameter inversion and control system, characterized in that: The system is used to control the separation layer grouting parameter inversion and control method according to any one of claims 1 to 7, and the system comprises: The equivalent mining height solution module is used to determine the building protection level and the maximum allowable deformation value, and to bring the maximum allowable deformation value into the derived functional expression of the equivalent mining height, and take the minimum value as the equivalent mining height; The module for calculating the volume of slurry after compaction is used to analyze the evolution law of overburden separation in coal seam mining according to the key layer theory, obtain the separation layer position, mining space size, separation layer development angle and sufficient mining angle according to comprehensive geological conditions, and equate the limit separation layer space to a three-dimensional geometric body. The volume of the three-dimensional geometric body is calculated according to the separation layer development angle and the sufficient mining angle, and the mining influence propagation coefficient f is determined. The volume of the slurry after compaction is obtained through the mining space volume; The slurry parameter determination module is used to determine the volume of slurry injected into the abscission layer through the slurry injection ratio, and to convert the compacted slurry into a three-dimensional geometric body according to the limit abscission space. After determining the similarity ratio according to the test bench size and the formation data, a proportionally reduced three-dimensional geometric body mold and a loading test bench are made; the mold is placed on the test bench, and slurry is injected into the mold to simulate abscission grouting. A rubber sheet is laid on the mold to make the mold evenly compressed, and the slurry water separation and compaction process is simulated. A loading test is carried out to determine the slurry water separation rate and the slurry compaction rate. The grouting control module is used to input the obtained slurry water separation rate and slurry compaction rate into the calculation formula of the slurry volume, calculate the parameters of the slurry injection ratio and grouting amount; evaluate the grouting settlement reduction effect, adjust the grouting process according to the evaluation effect, and achieve organic coordination between grouting and surface settlement reduction.

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