Similar simulation method and device for predicting spatial features of overlying strata separation, and storage medium

Abstract

According to the similar simulation method and device for predicting the spatial characteristics of the overlying strata separation layer and the storage medium, by collecting the geological parameters of a mining area site, the similarity ratio required by similar materials for building a similar model is calculated based on the similarity theory, and the ratio of the similar materials used for building the similar model is calculated; synchronously building a test platform comprising a frame, a loading system and a test system, and debugging monitoring equipment; laying a similar model in a layered manner according to the calculated material ratio, performing a simulation test through the similar model based on a mining area working face mining scheme, simulating working face advance according to a similar time ratio, collecting sensor data in real time, recording an overlying strata separation layer development record, and inferring a quantitative coal mine separation layer in combination with model inversion. The coal mine separation layer grouting and filling mining method system is further improved according to parameters such as key layer motion characteristics, separation layer space development and grouting pressure related to grouting and filling mining, and technical support is provided for scientific design and engineering implementation of separation layer grouting and filling mining.

Description

Technical Field

[0001] This invention relates to the field of spatial characteristic prediction technology of overburden delamination in the mining engineering field, specifically to a similar simulation method, equipment and storage medium for predicting the spatial characteristics of overburden delamination. Background Technology

[0002] Thick, hard rock strata (even extremely thick ones) exist in many underground mining areas in my country. Typical examples include the Yanzhou, Huaibei, Yima, and Datong mining areas. These thick, hard rock strata range in thickness from tens to hundreds of meters and are characterized by high strength, good integrity, and a wide overhang. During mining, they easily form "high and large" overburden space structures and "overburden separation spaces" below them. While these structures and spaces are temporarily stable, under long-term conditions, they can easily lead to energy accumulation in the structure and storage of gas and mine water in the space. As the mining area and disturbance increase, large-scale instability and displacement of the overburden space structure may occur, causing mine earthquakes, rock bursts, and abnormally high levels of stored gas and mine water, posing a threat to coal mine safety.

[0003] Typical examples include: On April 25, 2009, during the excavation of the No. 10 coal face in the II1026 machine roadway of Haizi Coal and Power Company, a massive igneous rock (approximately 120m thick) suddenly became unstable, triggering a coal and gas outburst accident in the delamination space. The outburst amounted to 656 tons of coal and 13,210 m3 of gas, resulting in one death; On November 3, 2011, a rockburst accident induced by a strong mine earthquake caused by the movement of a massive conglomerate (approximately 500m thick) occurred at Yima Qianqiu Coal Mine, resulting in 10 deaths, 64 injuries, and direct economic losses of nearly 100 million yuan.

[0004] Before the thick, hard rock layer breaks, the upper-level thick, hard rock layer is in a suspended state, while the lower-level rock layer fractures and forms a separation space. The suspended thick, hard rock layer accumulates energy, and the separation space stores hazardous substances such as gas and mine water. When the thick, hard rock layer breaks, the upper-level thick, hard rock layer suddenly breaks, releasing elastic potential energy and gravitational potential energy, resulting in hazards such as mine earthquakes and rock bursts. On the other hand, after the break, the suspended state disappears and "presses" downward into the separation space, forcing the stored hazardous substances such as gas and mine water to protrude into the surrounding mining space along the fissure channels of the goaf, resulting in hazards such as coal and gas outbursts and mine water outbursts.

[0005] Based on the actual situation of mine disasters induced by the fracture of thick and hard rock strata, theoretical research and mining practice have shown that overburden delamination technology is the main means of preventing and controlling mine disasters induced by the fracture of thick and hard rock strata. Therefore, in order to achieve a scientific and reasonable overburden delamination grouting effect, predicting the spatial characteristics of overburden delamination and determining key parameters are prerequisites. Domestic scholars have carried out targeted theoretical analysis, numerical simulation and field testing.

[0006] However, existing technologies still have certain limitations: In terms of theoretical analysis and numerical simulation, theoretical or numerical analysis alone cannot fully represent the real situation, and the results have limitations. Furthermore, field testing needs to take into account production and is not repeatable, making it impossible to conduct repeated variable changes experiments, resulting in poor comparative effects.

[0007] In summary, there is currently no mature method for determining key parameters of overburden delamination space based on simulation experimental results. It is necessary to improve a similar simulation method for predicting the spatial characteristics of overburden delamination and its key parameters. Summary of the Invention

[0008] The present invention proposes a similar simulation method, equipment and storage medium for predicting the spatial characteristics of overburden delamination, which can further improve the coal mine delamination grouting and filling mining method system, provide technical support for the scientific design and engineering implementation of delamination grouting and filling mining, and at least solve one of the technical problems in the background art.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A mobile source emissions prediction method based on time-series feature migration performs the following steps using computer equipment: S1, collect on-site geological parameters of the mining area, and calculate the similarity ratio and similarity time ratio required for building the similar model using similarity theory; S2, based on the similarity ratio and the geological parameters of the mining area, calculates the ratio of similar materials used in the construction of the similar model, and simultaneously builds a test platform including a frame, loading and testing system. The similar model is laid in layers according to the calculated material ratio, and sensors are buried in the coal seam floor and key rock strata of the similar model. S3, based on the mining scheme of the working face in the mining area, conducts simulation tests through similar models, simulates the advancement of the working face according to the similar time ratio, collects rock stress, displacement and deformation data monitored by sensors in real time to construct the original monitoring dataset, and records the development of overburden delamination simultaneously; S4 uses the original monitoring dataset, overburden delamination development records, similarity ratios, and on-site geological parameters of the mining area, combined with model transformation, to back-calculate the key parameters in the on-site geology of the mining area that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock layers in the overburden delamination.

[0010] Optionally, in S1, the collected geological parameters of the mining area include: stratification information of rock layers; geometrical parameters of each rock layer, unit weight parameters of each rock layer, elastic modulus parameters of each rock layer, uniaxial compressive strength parameters of each rock layer, Poisson's ratio parameters of each rock layer, and dynamic parameters of each rock layer. Meanwhile, mining time parameters of the mining face are obtained based on the mining plan of the mining face; The similarity ratio C of the similarity simulation test model was calculated using similarity theory. The calculation process is as follows: Let the geometric similarity ratio be... The dimensions of the rock strata in the mining area in three mutually perpendicular directions are as follows: , and The corresponding dimensions of the similar models are respectively , and Where v represents the mining site and m represents the similarity model, the geometric similarity ratio of the i-th rock layer is... for:

[0011] Let the similarity ratio of bulk density be . , The unit weight is given by the i-th rock layer at the mining site. In the similar model, the unit weight of this rock layer is The similarity ratio of the unit weight of the i-th rock layer for:

[0012] Let the elastic similarity ratio be... , Represents the elastic modulus; the elastic modulus of the i-th rock layer in the mining area is: The elastic modulus of the corresponding rock strata in the similar model is The elastic modulus similarity ratio of the i-th rock layer is... for:

[0013] Let the intensity similarity ratio be , Represents compressive strength; the uniaxial compressive strength of the i-th rock layer in the mining area is... The uniaxial compressive strength of the corresponding rock strata in the similar model material is Then the similarity ratio of the uniaxial compressive strength of the i-th rock layer for:

[0014] Let Poisson's ratio be the similarity ratio. , This represents the Poisson's ratio. The Poisson's ratio for each rock stratum at the mining site is... The Poisson's ratio of the corresponding rock strata in the model is Then the Poisson's ratio similarity ratio of the i-th rock layer for:

[0015] Let the dynamic similarity ratio be... , The dynamic force represents the impact force when the rock strata break. Based on Newtonian mechanics, the dynamic similarity ratio of the i-th rock stratum is... for: ; Let the time similarity ratio be... , If the density is expressed as a unit weight, then the time similarity ratio is:

[0016] in, Indicates the test time of similar models. This indicates the mining time required for the working face in the mining area based on the mining plan.

[0017] Optionally, the specific implementation process of S2 is as follows: S21. Based on the stratification information of the rock strata at the mining site, construct a comprehensive rock strata columnar section. Then, using the similarity ratio parameter, calculate the required amount of similar materials including sand, calcium carbonate, and gypsum, and generate a proportioning table. S22, Keep the test bench clean, and place protective plates of a specified height on both sides of the test bench to assist in model forming. The height of the protective plates gradually increases as the height of the model increases. S23, Weigh the required amount of similar materials for each layer according to the proportion table, then mix each layer of similar materials evenly, add water and stir. The production order of each layer is to lay them up layer by layer from the bottom layer. S24. Calculate the amount of similar materials for each rock layer based on the comprehensive rock layer columnar diagram, the proportion of similar materials selected for each rock layer and the model size. Transfer the mixed wet material to the test bench, spread it evenly, then flatten it with a flat plate and check whether it is flat with a level. S25. When making different rock strata, in order to make the model reflect the real rock strata movement, a layer of mica powder is evenly sprinkled on the surface of the previous layer to prevent the two adjacent layers from sticking together due to pressure, so that the model produces a layered effect. S26. For thicker layers, repeated layering is required, with mica powder covering the layers. The amount of mica powder covering the layers should be less than the amount of mica covering the different rock layers. S27, During the model making process, sensors are embedded in the simulated coal seam floor and key rock strata.

[0018] Optionally, in S27, key strata include main key strata and subkey strata; and the methods for determining whether a stratum is a key stratum include: Load method: Let the first coal seam above the roof be The thickness of the rock strata is Elastic modulus and density Calculate the load applied by the nth layer to the 1st layer. Where q represents the load, the expression is:

[0019] Among them, if ,but The layer that is locally critical is called a subcritical layer; When n represents all rock strata from the coal seam to the surface, the overall key stratum that can bear the overall rock stratum load is called the main key stratum. Bending stiffness method: Let the first coal seam above the roof be The thickness of the rock strata is and elastic modulus is Calculate the first The flexural stiffness of the rock strata are as follows:

[0020] If the following exists within a localized area of ​​the rock strata:

[0021] Then it can be determined that the i-th layer is a subcritical layer; Where n represents the number of rock layers, k represents the number of rock layers less than n (i.e., k < n), and d represents the cross-sectional width of the rock layer. If we calculate all rock layers within the range from the coal seam to the surface, that is, the total number of rock layers is n. If it exists within the entire range:

[0022] Among them, the number of n rock layers from the coal seam to the surface can determine that the i-th layer is the main key layer.

[0023] Optionally, the specific implementation process of S3 is as follows: S31, stress sensors were installed in the coal seam floor and key strata of similar models to collect data on the overlying strata load borne by the main key strata. Key layer density Ultimate tensile strength ,thickness and the height of the bottom of the main key layer from the coal seam being mined Simultaneously acquire overlying fracture angle Changes in data; S32 uses a total station to observe and record the displacement of the overlying strata during coal seam mining, and simultaneously collects the angle of full mining of the overlying strata. Data and mining thickness data r; S33, using a camera or video camera to record the evolution sequence of the overburden space structure in the goaf, including the overburden span data J of the main key layer, the timing of overburden fracture, the development scale of the delamination space, and the length of the curved part of the main key layer. S34 uses a ruler to measure the horizontal step distance of the model during the initial pressing of the key layer on the working face, which is used to calculate the maximum overhang span of the main key layer.

[0024] Optional, the key parameters in S4 that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock strata in the control of overburden delamination include: the limit mining scale at the beginning and end of the delamination at the bottom of the main key stratum, the maximum delamination height and area parameters at the bottom of the main key stratum, and the delamination grouting pressure range parameters to maintain the stability of the main key stratum; The calculation process for each key parameter is as follows: The ultimate mining scale when separation begins at the bottom of the main key stratum; Overburden fractures will propagate upwards at a specified angle. Based on the principle of the influence of the overburden fracture angle, let the overburden fracture angle be... When the width of the working face mining causes the overburden to fracture upwards and reach the bottom of the key stratum, the bottom of the main key stratum begins to separate, spatially satisfying... ; in, The minimum mining scale at which separation begins from the bottom of the main critical layer. The height of the bottom of the main key layer from the coal seam being mined; The ultimate mining scale at the bottom of the main key stratum when separation from the stratum ends; After the main critical layer reaches its maximum overhang span, it undergoes fracture movement under its own weight and the load of the overlying rock strata. Before fracture, the main critical layer is subjected to a uniformly distributed load. The tensile, shear, and compressive strengths of the thick, hard rock mass satisfy the condition that tensile strength is less than shear strength, which is less than compressive strength. Therefore, the thick, hard rock strata first undergo tensile failure. When the maximum tensile stress on the fixed side of the thick, hard rock strata reaches its ultimate tensile strength, fracture fissures are generated, and the conditions for movement are met.

[0025] in, The maximum span of the main critical layer. Ultimate tensile strength of the main critical layer The thickness of the primary critical layer, The bulk density of the primary critical layer, The load on the overlying strata borne by the main key layer is determined by theoretical calculations combined with similar simulations to determine the thickness of the overlying strata bearing the main key layer, and thus the magnitude of the load. The mining width dimension reached when the separation ends at the bottom of the main key layer. ,in The ultimate mining scale at which the separation of the main key layer ends at the bottom of the layer; Maximum delamination height at the bottom of the primary critical layer; The maximum subsidence of the underlying rock strata when the mining thickness is r, obtained by probability integral method, is: r, where The overburden subsidence coefficient is determined by the material of the overburden itself; The maximum delamination height r; Area of ​​the space separating the main critical layer from the bottom layer; Considering the bending deformation characteristics of the boundary region during the delamination process of the bottom strata of the main key layer, let the fully mined angle of the overlying strata be . The length of the curved portion of the main key stratum is The spatial relationships satisfy:

[0026] The area A of the separated space is calculated as follows:

[0027]

[0028] Control the grouting pressure parameters for stabilizing the main key layer; Assume the thickness of the coal seam below the surface is . The depth of the top of the key layer from the surface is then... The depth of the bottom of the main key layer from the surface is Let the bottom pressure of the grouting hole be... , and when hour, To correspond to the critical stress that penetrates the overlying strata of the roof, where, It is the average unit weight of the overlying strata of the main key layer.

[0029] Optional, the bottom pressure of the delamination grouting hole The following three special critical conditions exist as the basis for determining the range of grouting pressure required to maintain the stability of the main key layer; The first type, when At this time, the main critical layer is in a state of hydrostatic equilibrium, and the separation space above the main critical layer re-closes, which is within the safe range; The second type, when and At that time, that is The main key layer is in an upward bending state, and under the action of grouting pressure, the main key layer has an upward movement tendency, which is within the safe range; The third type, when Right now At that time, the grouting pressure can penetrate the overburden layer, causing the overburden and even all rock layers on the surface to fracture and move, which is within the dangerous range.

[0030] In another aspect, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0031] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0032] As can be seen from the above technical solution, the present invention overcomes the limitations of simple theoretical analysis and numerical simulation results that are difficult to match the actual field situation by constructing a similar simulation system of overburden-key layer that restores the real geological structure and mechanical properties of the field, and by combining multiple means of synchronous monitoring and quantitative calculation. At the same time, it avoids the shortcomings of field testing that need to take into account production, are not repeatable, and cannot carry out variable comparison experiments. It enables precise capture of the dynamic evolution of key layer fracture and overburden delamination, as well as the quantitative determination of core parameters for delamination prevention and control, including the delamination limit mining scale and grouting pressure range. This provides direct and reliable support for the scientific formulation of on-site mine disaster prevention and control plans, and effectively improves the safety of disaster prevention and control. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of the structure of a similar model in this invention; Figure 3 This is a schematic diagram showing the results of a simulation experiment using a similar model of the present invention; Figure 4 This is a schematic diagram of the spatial evolution of the delamination layer according to the present invention; Figure 5 This is a schematic diagram of the key parameters of the overlying delamination space in this invention; Figure 6 This is a schematic diagram illustrating mine disasters induced by the fracture of thick, hard rock strata in an embodiment of the present invention; Figure 7 This is a schematic diagram illustrating the use of delamination space for delamination grouting to control mine disasters induced by fractures in thick, hard rock strata, as described in this embodiment of the invention. Figure 8 This is a schematic diagram of the overburden separation grouting method of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0035] Example: like Figures 1-8 As shown, the Carboniferous coal seam in a certain mine in Shanxi Province is buried at a depth of 400-600 m, and the distance between it and the Jurassic coal seam is about 140-350 m. The coal seam is thick and has a relatively complex structure, with most of the Jurassic coal seam goaf above it. The total thickness of the coal seam in this Shanxi mine is about 86-95.86 m, with an average of 88.67 m. The roof of the coal seam is relatively hard, and the overlying rock structure is relatively intact.

[0036] However, as the mining area and disturbance impact further increase, it may cause large-scale instability and displacement of the overlying strata, leading to mine tremors, rock bursts, and abnormal outbursts of stored gas and mine water, posing hidden dangers to coal mine safety production, such as... Figure 6 As shown, overburden separation technology is a major means of preventing mine disasters induced by the fracture of thick, hard rock strata, such as... Figure 7 As shown.

[0037] Therefore, in order to achieve a scientific and reasonable overburden separation grouting effect, predicting the spatial characteristics of the overburden separation and determining key parameters are prerequisites. This paper proposes a similar simulation method, equipment and storage medium for predicting the spatial characteristics of the overburden separation, which can further improve the coal mine separation grouting and filling mining method system and provide technical support for the scientific design and engineering implementation of separation grouting and filling mining.

[0038] The mobile source emission prediction method based on time-series feature migration described in this embodiment performs the following steps using a computer device: S1, collect on-site geological parameters of the mining area, and calculate the similarity ratio and similarity time ratio required for building the similar model using similarity theory; Among them, the similarity model is a model made by using artificial materials that are similar to the physical and mechanical properties of natural rocks, and scaled down to a certain proportion according to the actual prototype of the mine, based on the similarity theory.

[0039] The geological parameters collected from the mining area include: stratification information of rock layers; geometrical parameters of each rock layer; unit weight parameters of each rock layer; elastic modulus parameters of each rock layer; uniaxial compressive strength parameters of each rock layer; Poisson's ratio parameters of each rock layer; and dynamic parameters of each rock layer. Meanwhile, mining time parameters of the mining face are obtained based on the mining plan of the mining face; The similarity ratio C of the similarity simulation test model was calculated using similarity theory. The calculation process is as follows: Let the geometric similarity ratio be... The dimensions of the rock strata in the mining area in three mutually perpendicular directions are as follows: , and The corresponding dimensions of the similar models are respectively , and Where v represents the mining site and m represents the similarity model, the geometric similarity ratio of the i-th rock layer is... for:

[0040] Let the similarity ratio of bulk density be . , The unit weight is given by the i-th rock layer at the mining site. In the similar model, the unit weight of this rock layer is The similarity ratio of the unit weight of the i-th rock layer for:

[0041] Let the elastic similarity ratio be... , Represents the elastic modulus; the elastic modulus of the i-th rock layer in the mining area is: The elastic modulus of the corresponding rock strata in the similar model is The elastic modulus similarity ratio of the i-th rock layer is... for:

[0042] Let the intensity similarity ratio be , Represents compressive strength; the uniaxial compressive strength of the i-th rock layer in the mining area is... The uniaxial compressive strength of the corresponding rock strata in the similar model material is Then the similarity ratio of the uniaxial compressive strength of the i-th rock layer for:

[0043] Let Poisson's ratio be the similarity ratio. , This represents the Poisson's ratio. The Poisson's ratio for each rock stratum at the mining site is... The Poisson's ratio of the corresponding rock strata in the model is Then the Poisson's ratio similarity ratio of the i-th rock layer for:

[0044] Let the dynamic similarity ratio be... , The dynamic force represents the impact force when the rock strata break. Based on Newtonian mechanics, the dynamic similarity ratio of the i-th rock stratum is... for: ; Let the time similarity ratio be... , If the density is expressed as a unit weight, then the time similarity ratio is:

[0045] in, Indicates the test time of similar models. This indicates the mining time required for the working face in the mining area based on the mining plan.

[0046] Reasonable determination of the "compensation" pressure p: The thickness of the rock layer under pressure by the similar device: Based on the above analysis and similarity relationship, determine the thickness and pressure of the rock layer under pressure by the similar device; By using S1 to obtain the strata layering, thickness and physical properties based on the borehole information, and then building a similar model of overburden-key layer by combining similarity ratio, the real structure and mechanical characteristics of the coal seam, main key layer and overburden in the field are accurately restored. This achieves a test vehicle that is closer to the actual field than simple theoretical analysis and numerical simulation, and solves the limitation of the disconnect between traditional theoretical analysis results and the field. S2, based on the similarity ratio and the geological parameters of the mining area, calculates the ratio of similar materials used in the construction of the similar model, and simultaneously builds a test platform including a frame, loading and testing system. The similar model is laid in layers according to the calculated material ratio, and sensors are buried in the coal seam floor and key rock strata of the similar model. Using a self-made planar similarity simulation test platform, the planar simulation test platform consists of three parts: a frame system, a loading system, and a testing system.

[0047] Its frame dimensions are 3.0m × 0.4m × 2.1m, with an effective height of 1.8m. Figure 2 As shown; In the figure, 1 is the frame structure of the experimental device, 2 is the wall of the similar simulated medium, 3 is the pressure-compensating light oil cylinder, 4 is the pressure equalization plate, 5 is the coal seam with excavation, 6 is the stress sensor, 7 is the deformation sensor, 8 is the data storage device, and 9 is the data analysis host. The testing system employs stress, strain, and non-contact full-field strain monitoring, enabling continuous monitoring of stress and deformation.

[0048] The experimental design was guided by similarity theory, and the selection of similar materials should satisfy the requirement that the structure of the similar materials and the prototype rock strata are similar in terms of main mechanical properties.

[0049] Similar materials mainly consist of two types of raw materials: fillers or aggregates and binders.

[0050] The fillers are often river sand, mica powder, talc, etc., while the binders include gypsum, paraffin wax, calcium carbonate, cement, etc. This experiment simulates gypsum as the binder, with calcium carbonate added, and river sand as the filler. Mica powder is sprinkled between the layers to create stratification. Different simulated objects and proportions can be achieved using similar materials with different ratios.

[0051] S21. Based on the drilling information and specific parameters such as similarity ratio, determine the amount of similar materials such as sand, calcium carbonate and gypsum required, screen the sand, and select the fine sand that meets the requirements, as shown in Table 1. Table 1. Model Material Proportions, Material Layers, and Laying Layers

[0052] S22, keep the test bench clean and place protective plates of a certain height on both sides of the test bench to facilitate model formation. The height of the protective plates gradually increases as the height of the model increases. S23, Weigh the materials according to the required amount of similar materials for each layer in the ratio table, then mix each layer of simulated material evenly, add water and stir. The production order of each layer is to lay them up layer by layer from the bottom layer.

[0053] S24. Calculate the amount of similar materials for each rock layer based on the comprehensive rock layer columnar diagram, the selected ratio number of each rock layer and the model size. Move the mixed wet material to the test bench, spread it evenly, then flatten it with a flat plate and check whether it is flat with a spirit level. During the flattening process, care should be taken to control the force. Do not use too much force, otherwise the simulated layer will be over-compacted and will not easily collapse during the test. When laying the lower rock layer, simply lay it flat and compact it, and avoid compacting it with force.

[0054] S25. When making models of different rock types and strata, in order to make the models reflect the real rock movement as much as possible, a layer of mica powder is evenly sprinkled on the surface of the previous layer to prevent the two adjacent layers from sticking together due to pressure, so that the model produces a layered effect. The amount of mica powder should be enough to evenly cover the layered surface; S26. For thicker layers, repeated layering is necessary, with each layer ideally 1.0–2.0 cm thick, and a few layers 2.0–3.0 cm thick. A suitable amount of mica powder should be applied between layers, with the amount of mica powder required less than that for different rock strata. The roof thickness should be smaller directly above the coal seam and below igneous rocks, generally 1.0–1.5 cm, to allow for greater separation space and better separation effect.

[0055] Because there is a similar scale between the prototype and the model, it is not suitable to create very thin rock layers. Appropriate adjustments can be made without affecting the overall effect. When converting to a model, the thin rock layer can be ignored, and the thickness can be added to the adjacent rock layers for simulation.

[0056] S27, During the model making process, sensors were buried near the coal seam floor and key rock strata, such as... Figure 4 As shown.

[0057] Key rock strata include main key strata and sub-key strata. The methods for determining whether a rock stratum is a key rock stratum include the following three methods. 1. Empirical method Thick, hard rock layers are often the main key layers. The movement of the main key layers leads to the movement of the entire overlying rock layers. The deformation of the main key layers can cause the coordinated movement of all the overlying rock layers. The different movement states of thick, hard rock layers determine the differences in the distribution characteristics of the overlying rock layers.

[0058] Therefore, taking into account the characteristics of rock strata such as hardness and thickness, sandstone layers exceeding 10m are usually considered as potential critical layers, while the last sandstone layer within the strata is generally the primary critical layer, and other thick and hard rock layers are considered as subcritical layers.

[0059] 2. Load method: Let the first coal seam above the roof be The thickness of the rock strata is Elastic modulus and density Calculate the load applied by the nth layer to the 1st layer. Where q represents the load, the expression is:

[0060] Among them, if ,but The layer that is locally critical is called a subcritical layer; When n represents all rock strata from the coal seam to the surface, the overall key stratum that can bear the overall rock stratum load is called the main key stratum. 3. Bending stiffness method: Let the first coal seam above the roof be The thickness of the rock strata is and elastic modulus is Calculate the first The flexural stiffness of the rock strata are as follows:

[0061] If the following exists within a localized area of ​​the rock strata:

[0062] Then it can be determined that the i-th layer is a subcritical layer; Where n represents the number of rock layers, k represents the number of rock layers less than n (i.e., k < n), and d represents the cross-sectional width of the rock layer. If we calculate all rock layers within the range from the coal seam to the surface, that is, the total number of rock layers is n. If it exists within the entire range:

[0063] Among them, the number of n rock layers from the coal seam to the surface can determine that the i-th layer is the main key layer.

[0064] By building a similar model to simulate the controllable mining process of the working face, the mining scale, rock strata parameters and other variables can be repeatedly adjusted to achieve the controllability of repeated variable tests. This achieves the effect of comparing the start and end scales of separation of the main and key strata and the fracture law under different working conditions, solving the problem that field tests cannot be repeated and variable comparisons cannot be carried out in the existing technology. S3, based on the mining face plan in the mining area, uses a similar model for simulation experiments. The working face advance is simulated according to a similar time ratio. Real-time data on rock strata stress, displacement, and deformation monitored by sensors are collected to construct the original monitoring dataset. Simultaneously, the development of overburden delamination is recorded, and the spatial evolution of delamination is shown as follows: Figure 4 As shown; Taking the carbonaceous series of a certain ore in Shanxi as an example for experimental simulation: The simulated average thickness of coal seams 3-5 is 11m, the mining height is 5.5m, the coal release height is 7.1m, and the distance from coal seam 14 is 140m. The simulated working face has a mining depth of 420m and a working face length of 200m. The lithology and thickness of the overlying strata are referenced from the columnar section of the coal seam of working face 8207 in a mine in Shanxi.

[0065] Theoretical calculations show that the mass of the iron block used to compensate for the pressure is 700 kg, and the height of the compensated stratum is approximately 290 m.

[0066] Test and analysis content: S31, stress sensors were installed in the coal seam floor and key strata of similar models to collect data on the overlying strata load borne by the main key strata. Key layer density Ultimate tensile strength ,thickness and the height of the bottom of the main key layer from the coal seam being mined Simultaneously acquire overlying fracture angle The changing data, the position of each parameter as follows Figure 5 A schematic diagram of key parameters of the overlying delamination space is shown.

[0067] S32 uses a total station to observe and record the displacement of the overlying strata during coal seam mining, and simultaneously collects the angle of full mining of the overlying strata. Data and mining thickness data r; S33, using a camera or video camera to record the evolution sequence of the overburden space structure in the goaf, including the overburden span data J of the main key layer, the timing of overburden fracture, the development scale of the delamination space, and the length of the curved part of the main key layer. S34 uses a ruler to measure the horizontal step distance of the model during the initial pressing of the key layer on the working face, which is used to calculate the maximum overhang span of the main key layer.

[0068] Specific experimental simulation results: 1) As the working face continues to advance, the roof strata above the goaf collapse. The overlying strata above the collapse zone are initially in a suspended and bent-down state, and then undergo delamination and fracturing movements. The delamination space of the overlying strata gradually develops from bottom to top (layers).

[0069] 2) The location of the overlying thick and hard rock layer during the overall excavation is basically consistent with the location of the key layer, and the spatial effect of the overlying rock separation layer of the thick and hard key layer is obvious.

[0070] 3) When the working face advances 50 m, the low-level subcritical layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is in the shape of an "I" and is 15.5 m wide, generating separation fissures 20 m away from the top of the coal seam.

[0071] 4) When the working face advances 70 m, the low-level subcritical layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is crescent-shaped, with a width of 34.6 m, a separation height of 2.1 m, and a distance of 38 m from the top of the coal seam.

[0072] 5) When the working face advances 90m, the low-level subcritical layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is crescent-shaped, with a width of 60.5m, a separation height of 2.9m, and a distance of 65.6m from the top of the coal seam.

[0073] 6) When the working face advances 110m, the low-level subcritical layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is crescent-shaped, with a width of 32.5m, a separation height of 2.8m, and a distance of 80.2m from the top of the coal seam.

[0074] 7) When the working face advances 130m, the main key layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is in the shape of an "I", with a width of 55.5m, a separation height of 3.3m, and a distance of 95m from the top of the coal seam.

[0075] 8) When the working face advances 150m, the main key layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is in the shape of an "I" with a width of 68.8m, a separation height of 3.6m, and a distance of 95m from the top of the coal seam.

[0076] 9) When the working face advances 170m, the main key layer above the goaf is in a suspended state, forming a separation space between it and the lower regular caving zone. The separation space is in the shape of an "I", with a width of 80.2m, a separation height of 3.6m, and a distance of 95m from the top of the coal seam.

[0077] 10) When the working face advances 200m, the main key layer above the goaf is in a broken state, the separation space below the main key layer is closed, that is, the separation space disappears, and the separation space above the main key layer is formed.

[0078] The above results are as follows Figure 3 The results of the similar model simulation experiment are shown in the diagram. The experimental simulation results clarified the dynamic evolution law of overburden delamination during the working face advancement, the dominant role of key layers, and the changes in delamination before and after fracture. It overcame the limitations of theoretical and numerical analysis and field testing, and provided quantitative indicators such as delamination location and size. This provides a direct basis for accurate on-site prediction of delamination and formulation of grouting prevention and control plans, thereby improving the pertinence and scientific nature of disaster prevention and control.

[0079] S4 uses the original monitoring dataset, overburden delamination development records, similarity ratios, and on-site geological parameters of the mining area, combined with model transformation, to back-calculate the key parameters in the on-site geology of the mining area that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock layers in the overburden delamination, and obtain parameter results that can guide engineering practice.

[0080] Among them, the key parameters in S4 that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock strata in the control of overburden delamination include: the limit mining scale of delamination at the beginning and end of the bottom of the main key stratum, the maximum delamination height and area parameters at the bottom of the main key stratum, and the delamination grouting pressure range parameters to maintain the stability of the main key stratum. The calculation process for each key parameter is as follows: The ultimate mining scale when separation begins at the bottom of the main key stratum; Overburden fractures will propagate upwards at a specified angle. Based on the principle of the influence of the overburden fracture angle, let the overburden fracture angle be... When the width of the working face mining causes the overburden to fracture upwards and reach the bottom of the key stratum, the bottom of the main key stratum begins to separate, spatially satisfying... ; in, The minimum mining scale at which separation begins from the bottom of the main critical layer. The height of the bottom of the main key layer from the coal seam being mined; The ultimate mining scale at the bottom of the main key stratum when separation from the stratum ends; After the main critical layer reaches its maximum overhang span, it undergoes fracture movement under its own weight and the load of the overlying rock strata. Before fracture, the main critical layer is subjected to a uniformly distributed load. The tensile, shear, and compressive strengths of the thick, hard rock mass satisfy the condition that tensile strength is less than shear strength, which is less than compressive strength. Therefore, the thick, hard rock strata first undergo tensile failure. When the maximum tensile stress on the fixed side of the thick, hard rock strata reaches its ultimate tensile strength, fracture fissures are generated, and the conditions for movement are met.

[0081] in, The maximum span of the main critical layer. Ultimate tensile strength of the main critical layer The thickness of the primary critical layer, The bulk density of the primary critical layer, The load on the overlying strata borne by the main key layer is determined by theoretical calculations combined with similar simulations to determine the thickness of the overlying strata bearing the main key layer, and thus the magnitude of the load. The mining width dimension reached when the separation ends at the bottom of the main key layer. ,in The ultimate mining scale at which the separation of the main key layer ends at the bottom of the layer; Maximum delamination height at the bottom of the primary critical layer; The maximum subsidence of the underlying rock strata when the mining thickness is r, obtained by probability integral method, is: r, where The overburden subsidence coefficient is determined by the material of the overburden itself; The maximum delamination height r; Area of ​​the space separating the main critical layer from the bottom layer; Considering the bending deformation characteristics of the boundary region during the delamination process of the bottom strata of the main key layer, let the fully mined angle of the overlying strata be . The length of the curved portion of the main key stratum is The spatial relationships satisfy:

[0082] The area A of the separated space is calculated as follows:

[0083]

[0084] Control the grouting pressure parameters for stabilizing the main key layer; Assume the thickness of the coal seam below the surface is . The depth of the top of the key layer from the surface is then... The depth of the bottom of the main key layer from the surface is Let the bottom pressure of the grouting hole be... , and when hour, To correspond to the critical stress that penetrates the overlying strata of the roof, where, It is the average unit weight of the overlying strata of the main key layer.

[0085] Among them, the bottom pressure of the delamination grouting hole The following three special critical conditions exist as the basis for determining the range of grouting pressure required to maintain the stability of the main key layer; The first type, when At this time, the main critical layer is in a state of hydrostatic equilibrium, and the separation space above the main critical layer re-closes, which is within the safe range; The second type, when and At that time, that is The main key layer is in an upward bending state, and under the action of grouting pressure, the main key layer has an upward movement tendency, which is within the safe range; The third type, when Right now At that time, the grouting pressure can penetrate the overburden layer, causing the overburden and even all rock layers on the surface to fracture and move, which is within the dangerous range.

[0086] In summary, the bottom pressure of the grouting hole used to maintain delamination can be determined. The range, such as Figure 8 As shown.

[0087] The measured data collected by S3 supports S4 in calculating core parameters such as the ultimate mining scale of the overburden separation, the maximum separation height, area, and grouting pressure range. This achieves the transformation from qualitative observation to quantitative calculation, enabling precise quantification of key indicators for overburden separation prevention and control. It provides direct basis for formulating grouting timing and pressure control plans on-site, and improves the pertinence and reliability of mine disaster prevention and control.

[0088] On the other hand, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0089] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0090] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute any of the similarity simulation methods for predicting the spatial characteristics of overburden separation in the above embodiments.

[0091] It is understood that the systems, devices, and storage media provided in the embodiments of the present invention correspond to the methods provided in the embodiments of the present invention, and the explanations, examples, and beneficial effects of the relevant content can be referred to the corresponding parts of the above methods.

[0092] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0093] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0094] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0095] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A similarity simulation method for predicting the spatial characteristics of overlying delamination, characterized in that, Perform the following steps using a computer device: S1, collect on-site geological parameters of the mining area, and calculate the similarity ratio and similarity time ratio required for building the similar model using similarity theory; S2, based on the similarity ratio and the geological parameters of the mining area, calculates the ratio of similar materials used in the construction of the similar model, and simultaneously builds a test platform including a frame, loading and testing system. The similar model is laid in layers according to the calculated material ratio, and sensors are buried in the coal seam floor and key rock strata of the similar model. S3, based on the mining scheme of the working face in the mining area, conducts simulation tests through similar models, simulates the advancement of the working face according to the similar time ratio, collects rock stress, displacement and deformation data monitored by sensors in real time to construct the original monitoring dataset, and records the development of overburden delamination simultaneously; S4 uses the original monitoring dataset, overburden delamination development records, similarity ratios, and on-site geological parameters of the mining area, combined with model transformation, to back-calculate the key parameters in the on-site geology of the mining area that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock layers in the overburden delamination.

2. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 1, characterized in that: In S1, the collected geological parameters of the mining area include: the layering information of the rock strata; the geometric dimensions of each rock strata, the unit weight of each rock strata, the elastic modulus of each rock strata, the uniaxial compressive strength of each rock strata, the Poisson's ratio of each rock strata, and the dynamic parameters of each rock strata. Meanwhile, mining time parameters of the mining face are obtained based on the mining plan of the mining face; The similarity ratio C of the similarity simulation test model was calculated using similarity theory. The calculation process is as follows: Let the geometric similarity ratio be... The dimensions of the rock strata in the mining area in three mutually perpendicular directions are as follows: , and The corresponding dimensions of the similar models are respectively , and Where v represents the mining site and m represents the similarity model, the geometric similarity ratio of the i-th rock layer is... for: Let the bulk density similarity ratio be... , The unit weight is given by the i-th rock layer at the mining site. In the similar model, the unit weight of this rock layer is The similarity ratio of the unit weight of the i-th rock layer for: Let the elastic similarity ratio be... , Represents the elastic modulus; the elastic modulus of the i-th rock layer in the mining area is: The elastic modulus of the corresponding rock strata in the similar model is Then the elastic modulus similarity ratio of the i-th rock layer is... for: Let the intensity similarity ratio be , Represents compressive strength; the uniaxial compressive strength of the i-th rock layer in the mining area is... The uniaxial compressive strength of the corresponding rock strata in the similar model material is Then the similarity ratio of the uniaxial compressive strength of the i-th rock layer for: Let Poisson's ratio be the similarity ratio. , This represents the Poisson's ratio. The Poisson's ratio for each rock stratum at the mining site is... The Poisson's ratio of the corresponding rock strata in the model is Then the Poisson's ratio similarity ratio of the i-th rock layer for: Let the dynamic similarity ratio be... , The dynamic force represents the impact force when the rock strata break. Based on Newtonian mechanics, the dynamic similarity ratio of the i-th rock stratum is... for: ; Let the time similarity ratio be... , If the density is expressed as a unit weight, then the time similarity ratio is: in, Indicates the test time of similar models. This indicates the mining time required for the working face in the mining area based on the mining plan.

3. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 2, characterized in that: The specific implementation process of S2 is as follows: S21. Based on the stratification information of the rock strata at the mining site, construct a comprehensive rock strata columnar section. Then, using the similarity ratio parameter, calculate the required amount of similar materials including sand, calcium carbonate, and gypsum, and generate a proportioning table. S22, Keep the test bench clean, and place protective plates of a specified height on both sides of the test bench to assist in model forming. The height of the protective plates gradually increases as the height of the model increases. S23, Weigh the required amount of similar materials for each layer according to the proportion table, then mix each layer of similar materials evenly, add water and stir. The production order of each layer is to lay them up layer by layer from the bottom layer. S24. Calculate the amount of similar materials for each rock layer based on the comprehensive rock layer columnar diagram, the proportion of similar materials selected for each rock layer and the model size. Transfer the mixed wet material to the test bench, spread it evenly, then flatten it with a flat plate and check whether it is flat with a level. S25. When making different rock strata, in order to make the model reflect the real rock strata movement, a layer of mica powder is evenly sprinkled on the surface of the previous layer to prevent the two adjacent layers from sticking together due to pressure, so that the model produces a layered effect. S26. For thicker layers, repeated layering is required, with mica powder covering the layers. The amount of mica powder covering the layers should be less than the amount of mica covering the different rock layers. S27, During the model making process, sensors are embedded in the simulated coal seam floor and key rock strata.

4. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 3, characterized in that: In S27, the key rock strata include the main key strata and the sub-key strata; and the methods for determining whether a rock strata is a key rock strata include: Load method: Let the first coal seam above the roof be The thickness of the rock strata is Elastic modulus and density Calculate the load applied by the nth layer to the 1st layer. Where q represents the load, the expression is: Among them, if ,but The layer that is locally critical is called a subcritical layer; When n represents all rock strata from the coal seam to the surface, the overall key stratum that can bear the overall rock stratum load is called the main key stratum. Bending stiffness method: Let the first coal seam above the roof be The thickness of the rock strata is and elastic modulus is Calculate the first The flexural stiffness of the rock strata are as follows: If the following exists within a localized area of ​​the rock strata: Then it can be determined that the i-th layer is a subcritical layer; Where n represents the number of rock layers, k represents the number of rock layers less than n (i.e., k < n), and d represents the cross-sectional width of the rock layer. If we calculate all rock layers within the range from the coal seam to the surface, that is, the total number of rock layers is n. If it exists within the entire range: Among them, the number of n rock layers from the coal seam to the surface can determine that the i-th layer is the main key layer.

5. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 4, characterized in that: The specific implementation process of S3 is as follows: S31, stress sensors were installed in the coal seam floor and key strata of similar models to collect data on the overlying strata load borne by the main key strata. Key layer density Ultimate tensile strength ,thickness and the height of the bottom of the main key layer from the coal seam being mined Simultaneously acquire overlying fracture angle Changes in data; S32 uses a total station to observe and record the displacement of the overlying strata during coal seam mining, and simultaneously collects the angle of full mining of the overlying strata. Data and mining thickness data r; S33, using a camera or video camera to record the evolution sequence of the overburden space structure in the goaf, including the overburden span data J of the main key layer, the timing of overburden fracture, the development scale of the delamination space, and the length of the curved part of the main key layer. S34 uses a ruler to measure the horizontal step distance of the model during the initial pressing of the key layer on the working face, which is used to calculate the maximum overhang span of the main key layer.

6. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 5, characterized in that: The key parameters in S4 that affect the prevention and control of mine disasters induced by the fracture of thick and hard rock strata due to overburden delamination include: the limit mining scale at the beginning and end of delamination at the bottom of the main key stratum, the maximum delamination height and area parameters at the bottom of the main key stratum, and the delamination grouting pressure range parameters for maintaining the stability of the main key stratum. The calculation process for each key parameter is as follows: The ultimate mining scale when separation begins at the bottom of the main key stratum; Overburden fractures will propagate upwards at a specified angle. Based on the principle of the influence of the overburden fracture angle, let the overburden fracture angle be... When the width of the working face mining causes the overburden to fracture upwards to reach the bottom of the key stratum, the bottom of the main key stratum begins to separate, spatially satisfying... ; in, The minimum mining scale for separation starting from the bottom of the main key layer. The height of the bottom of the main key layer from the coal seam being mined; The ultimate mining scale at the bottom of the main key layer when separation from the layer ends; After the main critical layer reaches its maximum overhang span, it undergoes fracture movement under its own weight and the load of the overlying rock strata. Before fracture, the main critical layer is subjected to a uniformly distributed load. The tensile, shear, and compressive strengths of the thick, hard rock mass satisfy the condition that tensile strength is less than shear strength, which is less than compressive strength. Therefore, the thick, hard rock strata first undergo tensile failure. When the maximum tensile stress on the fixed side of the thick, hard rock strata reaches its ultimate tensile strength, fracture fissures are generated, and the conditions for movement are met. in, The maximum span of the main critical layer. Ultimate tensile strength of the main critical layer The thickness of the primary critical layer, The bulk density of the primary critical layer, The load on the overlying strata borne by the main key layer is determined by theoretical calculations combined with similar simulations to determine the thickness of the overlying strata bearing the main key layer, and thus the magnitude of the load. The mining width dimension reached when the separation ends at the bottom of the main key layer. ,in The ultimate mining scale at which the separation of the main key layer ends at the bottom of the layer; Maximum delamination height at the bottom of the primary critical layer; The maximum subsidence of the underlying rock strata when the mining thickness is r, obtained by probability integral method, is: r, where The overburden subsidence coefficient is determined by the material of the overburden itself; Maximum delamination height r; Area of ​​the space separating the main critical layer from the bottom layer; Considering the bending deformation characteristics of the boundary region during the delamination process of the bottom strata of the main key layer, let the fully mined angle of the overlying strata be . The length of the curved portion of the main key stratum is The spatial relationships satisfy: The area A of the separated space is calculated as follows: Control the grouting pressure parameters for stabilizing the main key layer; Assume the thickness of the coal seam below the surface is . The depth of the top of the key layer from the surface is then... The depth of the bottom of the main key layer from the surface is Let the bottom pressure of the delamination grouting hole be... , and when hour, To correspond to the critical stress that penetrates the overlying strata of the roof, where, It is the average unit weight of the overlying strata of the main key layer.

7. The similarity simulation method for predicting the spatial characteristics of overburden delamination according to claim 6, characterized in that: Bottom pressure of the delamination grouting hole The following three special critical conditions exist as the basis for determining the range of grouting pressure required to maintain the stability of the main key layer; The first type, when At this time, the main critical layer is in a state of hydrostatic equilibrium, and the separation space above the main critical layer re-closes, which is within the safe range; The second type, when and At that time, that is The main key layer is in an upward bending state, and under the action of grouting pressure, the main key layer has an upward movement tendency, which is within the safe range; The third type, when Right now At that time, the grouting pressure can penetrate the overburden layer, causing the overburden and even all rock layers on the surface to fracture and move, which is within the dangerous range.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the computer program is executed by the processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

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