325 results about "Coal pillar" patented technology

The invention discloses a mining section coal pillar goaf side concrete wall reinforcing method, and relates to the field of coal mining, and the method comprises the following steps: collecting section coal pillar geological parameters; calculating a boundary position of a plastic zone according to geological parameters of the coal pillar, and dividing the coal pillar into a broken zone, a fractured zone and an original structure zone; basic roof strata are determined according to geological parameters of the coal pillar, the bearing capacity of the basic roof strata is calculated, the basic roof strata with the minimum bearing capacity serves as a roof cutting target layer, and the hydrofracture roof cutting drilling depth needed for penetrating through the target layer is determined; the broken area range serves as the influence range of surrounding rock pressure calculation, the static load q applied to the concrete wall by the surrounding rock pressure is calculated, the static load q is corrected through a dynamic load coefficient, and a supporting load Q is obtained; and according to the support load Q, reinforcement parameters are determined. Aiming at the surrounding rock deformation and instability of the adjacent roadway on the section coal pillar gob side under the deep well mining condition, the method effectively controls the surrounding rock deformation and instability of the adjacent roadway caused by working face mining disturbance.

The invention provides a method for analyzing the dynamic stability of a slope containing a mining cavern group under the action of dynamic and static loads, and belongs to the technical field of analysis of the dynamic stability of the slope containing the mining cavern group. In order to solve the technical problem that complex mechanical behaviors of a slope containing a mining cave group under the dynamic and static load coupling effect are difficult to accurately consider because most of existing slope stability analysis aims at single static load or dynamic load working conditions, the technical scheme adopted by the invention comprises the following steps: collecting end slope mining coal pillars and rock samples of rock stratums overlying the end slope mining coal pillars, and testing physical and mechanical parameters of the rock samples; the physical and mechanical parameters of all the rock stratums are finally selected in combination with related production materials of the mining area; calculating a shear strength parameter of the rock mass after the rock is damaged under the action of cyclic blasting vibration; calculating shear strength parameters of the end slope mining area-evolved weak layer under the action of blasting vibration; the stability of the slope containing the mining cavern group under the blasting vibration effect is calculated; the method is applied to the stability analysis of the power of the slope containing the mining cavern group.

The invention discloses a visual three-dimensional test device for grouting reinforcement and effect of a mine boundary coal pillar under a thin unconsolidated formation, and relates to the technical field of similar test simulation equipment for grouting reinforcement of the mine coal pillar. The device comprises a test support, an internal frame, a model storage box, a loading plate assembly, a model cutting mechanism, a vertical loading mechanism, a horizontal loading mechanism, a signal acquisition and processing mechanism, a three-dimensional test model, a coal mining simulation mechanism, a model grouting mechanism, a model separation mechanism and an effect visualization mechanism. According to the coal seam mining simulation mechanism, step-by-step, segmented and controllable excavation of a three-dimensional similar model in a closed space can be achieved, generation, expansion and penetration of coal seam mining roof rock stratum cracks are inverted, and the evolution process of a water guide channel is finally formed. According to the invention, the diffusion and runout characteristics of the grouting reinforcement slurry for the boundary coal pillar of the mine under the thin unconsolidated formation can be truly simulated, and the dynamic process of diffusion, condensation and reinforcement of the coal pillar by the slurry in the water-guiding damage fracture can be reproduced.

The invention provides a method for determining advanced controllable roof cutting parameters of a thick and hard roof of a coal mine stope face, which comprises the steps of engineering general situation field investigation and survey, in-situ geomechanical test, goaf roof thickness / thin plate theoretical analysis, coal pillar or filling body vertical load theoretical analysis, numerical simulation calculation and engineering test verification. Analyzing the mechanical behavior of the working face roof based on a plate theory, verifying the correctness of a theoretical model through measured data, and changing boundary conditions to predict the mechanical behavior of the roof after roof cutting; the method comprises the following steps: analyzing the vertical load of a coal pillar or a roadside support body after roof cutting and the influence rule of roof cutting height and angle on the roadside support body through a mechanical model, and preliminarily obtaining better roof cutting parameters; by establishing a numerical model of different topping parameter combinations, different performance parameters are used for comparing and evaluating different topping parameters, so that the optimal topping parameter is determined; according to the method, advanced controllable roof cutting of the hard roof of the coal seam is achieved, and the mine pressure treatment effect in mining is predicted.

The invention discloses a grouting and filling method for a cross-layer area of a coal pillar group in a residual mining area, and relates to the technical field of coal mining, which comprises the following steps of: (1) selecting a key layer; (2) a drill hole is constructed in the key layer, a directional initial crack is formed in the drill hole through frosted water jet cutting, then the two ends of the drill hole are set, and the initial crack is expanded to form a crack network in the mode that high-pressure fluid is injected into a hole sealing section; (3) grouting materials are adopted for conducting segmented grouting construction on the drill holes in the step (2), specifically, firstly, low-viscosity grout is used for filling a crack network formed through fracturing, then medium-viscosity grout is used for filling a coal pillar plastic area influenced by mining, and finally high-viscosity grout added with an accelerating agent is used for filling roof fractured rock mass and goaf and goaf roadways; and (4) after the slurry is solidified, a coal pillar-slurry vein body-overlying strata composite bearing structure is formed. According to the invention, the rock mass cohesive force and overall strength of the re-mining area can be obviously enhanced, and the stability of re-mining roadways and working face surrounding rocks is improved.

The invention discloses a key layer presplitting settlement control method based on overlying strata fracture angle arrangement. The method comprises the steps that geological mining parameters of a target mine are collected and determined; based on the physical and mechanical parameters of each rock stratum, determining the horizon height of the key stratum in combination with a thick and hard rock stratum judgment criterion; according to coal seam mining parameters and overlying strata lithology, the height of a water flowing fractured zone is judged, and high and low horizon classification is conducted on the water flowing fractured zone by combining the horizon of the key horizon; according to the development law of overlying strata damage along the fracture angle from bottom to top, the presplitting position in the horizontal direction of each layer key layer in the presplitting range is calculated and determined, and full-section directional presplitting cutting is carried out; based on thick and hard rock stratum mining-induced stress distribution characteristics and a damage deformation transmission mechanism, a working face moving boundary and a reduction distance of a building (structure) protection coal pillar after key stratum presplitting are calculated and determined. According to the method, presplitting implementation is guided based on the key layer fracture rule, and a new technical approach is provided for subsidence control of the mining area.

The invention relates to the technical field of coal mining and mine safety engineering, and discloses a coal pillar stability dynamic monitoring and pressure relief control method for gob-side entry driving, which comprises the following steps: collecting multi-field coupling signals of a coal pillar, and collecting environmental data of a roadway; analyzing the stability of the coal pillar according to the multi-field coupling signal, and when an analysis result does not meet a stable condition and the environmental data does not meet an environmental condition, generating a cooperative control instruction of the high-pressure water jet system integrated with the solid-liquid waste collection device; executing directional hydraulic fracturing pressure relief operation on the coal pillar area according to the cooperative control instruction, and monitoring the stress distribution and fracture closing state of the coal pillar after pressure relief; hydraulic parameters of the high-pressure water jet system are adjusted according to the coal pillar stress distribution and the fracture closed state; and when the coal pillar recovers the stable state and the environmental data meet the environmental conditions, controlling the pressure relief operation of the coal pillar area according to the cooperative stop instruction. According to the method, the accuracy of dynamic monitoring and pressure relief control of the stability of the coal pillar of gob-side entry driving can be improved.

The invention provides a non-uniform load lower end slope mining supporting coal pillar dynamic stability evaluation method, and belongs to the technical field of end slope mining supporting coal pillar dynamic stability evaluation. In order to solve the technical problem that under the condition that blasting vibration and overlying strata coupling effects are not considered in a conventional coal pillar stability evaluation method, risks possibly exist in personnel and an end slope coal mining machine due to supporting coal pillar parameter design, the adopted technical scheme comprises the steps that end slope retention coal and overlying strata rock samples are collected; testing physical and mechanical parameters of the retained coal and the rock sample of each overlying rock stratum; based on the dynamic response and deformation rule of the supporting coal pillar under the coupling action of the non-uniform static load and the blasting dynamic load, establishing a supporting coal pillar dynamic instability criterion based on a sudden change theory; based on the relation model of the maximum bending moment and the tensile stress of the coal pillar roof under the dynamic-static load coupling effect, a roof dynamic instability criterion based on the strength theory is established; the method is used for controlling the stability of the open pit coal mine end slope mining supporting coal pillar.

The invention discloses a rock burst risk identification method for a coal pillar, and the method comprises the steps: constructing a multi-source monitoring data set, extracting a plurality of dynamic characteristic parameters, such as micro-seismic energy and stress concentration ratio, constructing a comprehensive precursor score in combination with a coal pillar simulation critical value, and introducing a classification model to carry out the risk grade identification. The problem that a traditional method depends on a single index and early warning staticization is solved, meanwhile, through fusion of finite element simulation and real-time monitoring, the expression ability of the stability evolution process of the coal pillar is enhanced, the systematic recognition process from feature extraction, score evaluation to early warning output is achieved, the accuracy and adaptability of rock burst risk recognition are enhanced, and the risk recognition efficiency is improved. And the capabilities of high-discrimination risk discrimination and field application adaptability are realized.

The invention discloses a goaf remaining coal pillar stability comprehensive evaluation method based on InSAR and acoustics fusion, and belongs to the field of mine safety evaluation.The goaf remaining coal pillar stability comprehensive evaluation method comprises the steps that an SAR satellite suitable for a mining area is selected, SAR satellite image data of the mining area is obtained, sequential deformation analysis is conducted, the deformation rate and an accumulated deformation graph of the mining area are obtained, and a settlement abnormal area of the mining area is recognized; a coal pillar area of a mining area is drilled, and an ultrasonic logging device, an inter-well sound wave chromatography system and a sound emission monitor are arranged; performing comprehensive analysis on all the obtained data, and constructing a coal pillar stability evaluation model; and through the coal pillar stability evaluation model, grading the coal pillar stability, and predicting a coal pillar instability risk. According to the InSAR and acoustics fused goaf remaining coal pillar stability comprehensive evaluation method provided by the invention, high-precision evaluation of the coal pillar stability is realized through combination of earth surface deformation monitoring and deep coal pillar structure detection.

The invention discloses a method for predicting rock burst in a remaining coal pillar area based on monitoring data, and the method comprises the steps: constructing a synchronized and denoised basic data layer through the space-time interpolation completion of multiple types of monitoring data and a dual-channel noise suppression mechanism, and achieving the classification response of a sudden change signal and a progressive risk in combination with an adaptive risk weighting strategy, thereby achieving the prediction of the rock burst in the remaining coal pillar area. And meanwhile, by constructing a dynamic graph structure evolved along with time and combining a graph convolutional network and a circulating unit, combined modeling of a space coupling relationship and an evolution trend is realized, and the identification capability of the weak chain risk is improved while the prediction stability is guaranteed.

The invention provides a roadway surrounding rock stability judgment method and a classified supporting method, and relates to the technical field of soil layer or rock drilling and mine safety. The method comprises the following steps: S1, determining roadway surrounding rock stability influence factors; s2, dividing a rock mass strength index, a surrounding rock stress index, a surrounding rock integrity index, a roadway size index, a coal pillar ruler habit index, a water spraying index and the like; s3, determining a roof strength stress coefficient, a roof integrity coefficient and a side loosening coefficient; s4, performing field investigation or testing to obtain a classification index value, and determining an index threshold value through a fuzzy clustering method; s5, determining classification of non-impact roadways and impact dangerous roadways according to the roadway impact dangerousness and the impact danger index; and S6, determining a roadway support mode according to the roadway surrounding rock stability classification. According to the method, more comprehensive influence factors are considered, parameters are more convenient to obtain, values of factors required by field test classification indexes are facilitated, and scientific support of roadway surrounding rocks is achieved.

The invention discloses a digital twinning-based intelligent control system and method for butt-joint drilling of a horizontal well penetrating through a goaf coal pillar, and relates to the technical field of drilling and coal mine safety. The system comprises a data acquisition and transmission module for acquiring and transmitting multi-source heterogeneous data of a to-be-drilled goaf; the digital twinning module constructs a digital twinning model; the while-drilling perception and dynamic risk assessment module is used for acquiring and processing while-drilling measurement data and fusing the data with digital twinborn model data to generate a visual dynamic risk field; the intelligent decision and control module is used for generating a safe drilling path and a drilling parameter control instruction; the execution and well control module executes the control instruction and regulates and controls drilling equipment and a well control device; and the man-machine interaction module is used for displaying the risk information and realizing man-machine According to the method, the conversion of drilling safety from passive response to active prediction and intelligent control is realized, and the safety and the success rate of drilling operation penetrating through the goaf coal pillar are improved.

The invention relates to a mine earthquake and rock burst hybrid dynamic disaster discrimination method and system, and the method comprises the steps: carrying out the numerical simulation of overlying strata motion evolution and stress field evolution according to geological data, and obtaining an analogue simulation result; according to the analogue simulation result, establishing a mechanical model in which the island coal pillar and the target rock stratum are simultaneously subjected to uniformly distributed load and horizontally concentrated stress; deducing an expression of dynamic and static load stress caused by fracture instability of the target rock stratum according to the mechanical model; and constructing a discriminant of the mine earthquake and rock burst composite dynamic disaster according to the dynamic and static load stress expression by combining a dynamic and static load superposition theory so as to reveal the occurrence mechanism of the mine earthquake and rock burst composite dynamic disaster of the extremely thick hard rock downhill coal pillar, and predicting the occurrence of the mine earthquake and rock burst composite dynamic disaster according to the discriminant.

The invention provides a close-distance coal seam dynamic coal-pillar-free mining method based on intelligent monitoring, which comprises the following steps: deploying a multi-parameter sensor network in an upper coal seam working surface, a lower coal seam working surface and overlying strata, monitoring the stress, displacement and fracture development state of the overlying strata in real time, and dynamically optimizing roof cutting parameters and a mining sequence in combination with a hydraulic fracturing intelligent regulation and control technology; in the mining process, monitoring data are analyzed through an MATLAB algorithm, an overlying strata caving prediction model is generated, and the overlying strata caving time and range are guided; and meanwhile, the carbon fiber reinforced polymer nano composite material is adopted for reinforcing the roadway side in the lower coal seam gob-retaining roadway, so that the structural stability is improved. Through intelligent monitoring and dynamic regulation and control, accurate control over overlying strata collapse is achieved, the stress concentration risk is reduced, and the resource recovery rate and mining safety are improved.

The invention discloses a mineshaft and industrial square coal pillar mining method. The mineshaft and industrial square coal pillar mining method comprises the following steps that S1, a well wall penetrating through a coal seam is replaced with a retractable wood crib; s2, square coal pillars on the periphery of the shaft are subjected to stoping; s3, a mining working face is arranged to be a small working face parallel to the trend or inclination direction of the coal seam, and the industrial square coal pillars are mined in a spiral mining sequence; s4, in the mining process, earth surface monitoring and well wall deformation monitoring are conducted on a shaft; and S5, in the mining process, the stress concentration position or the damage position in the shaft is protected. According to the mining method, the industrial square coal pillars can be effectively recycled, the service life of a mine is prolonged, and coal resources are fully mined, so that the mining rate of the coal resources is increased, and convenience is provided for mining operation of the coal resources.

The embodiment of the invention discloses a gob-side entry driving coal pillar unilateral operation self-anchoring opposite-penetrating anchor cable device and an anchoring method thereof, relates to the technical field of coal pillar anchoring, and can effectively solve the problem that an upper section goaf of a coal pillar is closed, construction is only performed on one side of a lower section, and opposite-penetrating anchor cable fixing and supporting cannot be achieved. The safety and the stability of the gob-side roadway are improved; the anchor cable device comprises an anchor cable body, a self-anchoring device is arranged at one end of the anchor cable body, and an anchor cable fastening device is arranged at the other end of the anchor cable body. The self-anchoring device comprises a self-locking device, the self-locking device comprises a self-locking device main rod, one end of the self-locking device main rod is connected with the push plate, the other end of the self-locking device main rod penetrates through a hollow hinge base hinged to a steel plate set, and a self-locking mechanism is arranged on the self-locking device. One end of the push plate is connected with the self-locking device main rod; the opposite sides of the steel plates in the steel plate group surround the self-locking device main rod; the steel plate set, the push plate and the hinged base form a containing cavity, and an anchoring agent is contained in the containing cavity.

The invention discloses a method for calculating critical stress of rock burst of a small coal pillar free roadway, which comprises the following steps of: S1, simplifying a stress-strain relation of a coal-rock mass into a bilinear constitutive relation, and establishing a free roadway mechanical analysis model by taking the center of a goaf as an origin of coordinates according to stress and deflection characteristics of roofs in different areas; s2, parameters of the basic equation of the free roadway mechanical analysis model are solved; s3, solving the critical stress of the rock burst of the free roadway according to an energy criterion; s4, solving the critical stress of the rock burst of the free roadway according to a stress criterion; and S5, verifying calculation results of S3 and S4 to obtain more accurate critical stress of rock burst of the free roadway. The calculation method provided by the invention is more scientific, the asymmetry characteristic of the free roadway and the effect in the friction sliding rock burst generation process between the coal rock layers are considered, the blank in the aspect of free roadway mechanical modeling is filled, two theoretical solutions are given, and the error is smaller.

This invention belongs to the field of coal mining technology, specifically relating to a water storage method in aeolian sandy aquifer mining areas. This invention innovatively utilizes directional drilling to connect aeolian sandy aquifers in open-area zones with those in non-open-area zones, improving rapid cross-regional water recharge and significantly increasing the total water storage capacity of the entire mining area. To prevent large amounts of water from being discharged through surface springs, coal pillars are used to alter the original seepage path of the aquifers. The subsidence of the coal pillar area is smaller than that of the mining area, blocking or reducing spring discharge and increasing the migration path of groundwater, thereby increasing infiltration. This invention increases the amount of water resources infiltrated from aeolian sandy ...

The invention aims to provide a mining process for recovering section coal pillars in a double-wing retreating type continuous mining and continuous filling mode, and belongs to the technical field of coal mining. Coal pillar resources of a working face section are completely recovered through three process steps of branch roadway tunneling, mining chamber stoping and lagging filling, coal resources are avoided, and the mining efficiency is improved. Especially, resource loss caused by scarce high-quality coal resources due to the fact that section coal pillars cannot be recycled is avoided, and the resource recycling rate is increased.

The invention relates to the technical field of mining engineering and coal mine roadway surrounding rock control, and discloses a face-mining working face small coal pillar roadway surrounding rock control method which comprises the following steps: reinforcing roadway bearing pressure by reinforced concrete pier studs: in a mining super front section small coal pillar roadway, pouring a row of reinforced concrete pier studs along the center line of the small coal pillar roadway, the upper end of the reinforced concrete pier column abuts against the center area of the vault of the small coal pillar roadway. The frosted water jet directional roof cutting pressure relief technology is adopted for lateral roof cutting at the advanced section of the stope, so that the hard rock stratum of the top plate of the stope face collapses as soon as possible; a plurality of steel pipe cast-in-place piles arranged at intervals are arranged at the bottom corners of the small coal pillar roadway, and a plurality of crown beams are fixedly connected to the ends of the steel pipe cast-in-place piles. The method for controlling the surrounding rock of the small coal pillar roadway of the face-mining working face is convenient to construct and good in economic benefit.

The invention discloses a working face staggered layout method, product and equipment for coal mining ground fissures, and belongs to the technical field of mining subsidence and ecological restoration. The method comprises the steps that S1, the overall layout mode of upper and lower coal seam working faces is determined; s2, determining core mining parameters of the working face; s3, determining an external error distance or an internal error distance through numerical simulation; s4, acquiring surface subsidence data and verifying the surface subsidence data; and S5, determining the mining sequence of the upper coal seam working face and the lower coal seam working face according to the layout mode, and designing a whole-process production system to realize the landing of a production scheme. According to the method, the goal of weakening coal mining ground fissure development from the source is achieved by reasonably arranging the working faces of the upper and lower coal seams and adjusting the staggered distance of the working faces of the upper and lower coal seams without abandoning coal pillar resources and increasing the roadway tunneling cost, the ground fissure development degree can be weakened from the source, and the coal mining efficiency is improved. The problems of multiple procedures, long period, poor effect and the like of a traditional method are solved.

The application discloses a linear structure under thick coal seam protection coal pillar filling mining method and relates to the technical field of coal seam mining. The mining method comprises the following steps: firstly, determining the length of the thick coal seam protection coal pillar under the linear structure, the thickness of the limited thickness mining and the filling scheme; secondly, when the thick coal seam is fully mined to the left end of the protection coal pillar, the linear structure protection coal pillar is limited thickness mined, and the "throwing gangue + grouting" filling body is formed at the left end of the protection coal pillar; the working face continues to advance, and the paste body filling is carried out in the limited thickness mining goaf; then, the working face continues to advance, and the original gangue filling is carried out in the limited thickness mining goaf; the first two steps are repeated in sequence until the protection coal pillar is mined; finally, the protection coal pillar is limited thickness mined, a distance is continuously mined, the "throwing gangue + grouting" filling body is formed at the right end of the protection coal pillar, and the working face continues to advance after the filling body is connected. The application can maximize the liberation of the overburden coal resources under the linear structure and can improve the coal recovery rate.

The invention discloses a coal pillar damage threshold prediction and crack automatic identification system based on deep learning. The system comprises six units including a multi-dimensional heterogeneous coal pillar data acquisition and fusion unit, an optimization hypergraph neural network feature extraction unit and the like. The system integrates elastic modulus, Poisson's ratio and other multi-source data through a multi-dimensional heterogeneous coal pillar data acquisition and fusion unit, constructs a hypergraph structure by using an optimized hypergraph neural network to extract implicit features, establishes parameter and damage threshold nonlinear mapping based on a multi-dimensional heterogeneous coal pillar data analysis model, and completes accurate calculation through a specific formula. Through cooperation of all unit sub-modules, deep analysis of coal pillar crack image features is realized, and finally, cracks are automatically identified in combination with image features and a damage threshold prediction result. The system overcomes the problems that traditional multi-source data fusion is difficult and the model prediction precision is low, provides an intelligent monitoring means for coal mine safety production, and has technical advancement and application value.

The application discloses a coal column reinforcing method for waste resource utilization, which is characterized by the following steps: ensuring the stability of the coal column, designing a groove on the coal column, pasting a groove mold on the coal column, embedding the groove mold, filling the groove mold with coal gangue concrete, and prefabricating the groove mold. The application can ensure the stability of the coal column, design a groove on the coal column, prefabricate a groove mold, paste the groove mold on the coal column, embed the groove mold, fill the groove mold with coal gangue concrete, and make the construction operation simple. The application can effectively reduce the size of the coal column, improve the coal resource mining rate, avoid the waste of coal resources, and realize the resource utilization of the waste coal gangue.

The present application relates to the technical field of impact low pressure prevention and treatment, and particularly relates to a method for preventing and treating impact ground pressure in an overlying residual coal pillar influence area, which comprises the following steps: determining a key layer of surrounding rock above a working face to be mined and a residual coal pillar in an overlying layer as a preset fracturing layer; determining a fracturing area to be fractured of the preset fracturing layer through the working face to be mined and the residual coal pillar, and the projection of the fracturing area to be fractured in a gravity direction covers the working face to be mined and the residual coal pillar; drilling a horizontal well in the preset fracturing layer after setting a vertical shaft on the ground, and then fracturing the preset fracturing layer; and adjusting the fracturing operation through a crack extension rate in the fracturing process. The method for preventing and treating impact ground pressure in the overlying residual coal pillar influence area adjusts the fracturing operation according to the crack extension rate to pre-fracture the surrounding rock above the residual coal pillar, and improves the safety of coal mining.

This invention discloses a support structure and method for a small coal pillar roadway, belonging to the field of roadway support technology. The support structure includes a support base and a hydraulic push rod, with anti-retraction damping components symmetrically arranged on both sides of the hydraulic push rod. The anti-retraction damping components suppress the retraction of the hydraulic push rod when it is compressed. The anti-retraction damping components include a second support plate, a friction element, and two upper and lower fixing rods. A lubrication component is installed on the second support plate to lubricate the anti-retraction damping components. This invention can effectively reduce the friction between the components of the anti-retraction damping components and ensure the stability of the support structure in complex environments, providing a reliable guarantee for roadway safety.

The application provides a coal pillar recovery and filling method for a section of a working face before mining, and belongs to the technical field of coal mining and filling. The technical problems of coal pillar reservation, resource waste and safety hazards in traditional mining are solved. The technical scheme is as follows: a coal pillar recovery and filling method for a section of a working face before mining, comprising the following steps: S1, planning a to-be-mined working face one, a to-be-mined working face two and a working face section coal pillar, and sequentially dividing and combining the working face section coal pillar into areas; S2, recovering the coal resources in the combined area G1 and filling the coal pillar area with filling materials; S3, repeating the above step S2 to sequentially recover the coal resources in subsequent combined areas G2, G3,..., Gn and fill them. The beneficial effects of the application are as follows: the method cooperatively recovers the coal pillar and excavates the working face roadway, safely recovers the coal pillar, realizes coal-based solid waste resource disposal, has the advantages of safety, high efficiency, environmental protection and economy, and provides a sustainable mining solution for the mine.

The application discloses a residual coal pillar stability analysis method and device considering time effect, a medium and a product, relates to the field of coal resource mining, and comprises the following steps: constructing a generalized Kelvin model based on the geometric parameters and mechanical parameters of the residual coal pillar; performing residual coal pillar creep deformation analysis according to the generalized Kelvin model; constructing a coal pillar-roof coupling energy model based on a creep deformation equation; performing variational analysis on the coal pillar-roof coupling energy model based on the principle of minimum potential energy; obtaining the effective bearing time of the residual coal pillar according to the stability criterion and in combination with the geometric parameters of the residual coal pillar, the mechanical parameters of the coal body and the stiffness parameters of the roof; and performing secondary mining safety evaluation according to the effective bearing time. The application can effectively improve the scientificity and accuracy of stability evaluation in the secondary mining process of the residual coal pillar in the old mining area, reduce the safety risk of the secondary mining operation, and provide technical support for the safe and efficient development of residual coal resources.

The invention discloses a green pressure relief method for mine pressure display caused by multi-coal-seam mining remaining coal pillars, and belongs to the technical field of multi-coal-seam mining. According to the invention, through an intelligent decision-making system of multi-source data fusion, the problem of response lag of a traditional method is solved; a coupling technology of supercritical CO2 gas expansion pressure relief and a biodegradation hydraulic fracturing technology is adopted, low pollution and coal pillar structure protection in the pressure relief process are achieved, through a whole-process closed loop of'monitoring-prediction-decision-verification ', the problem of multi-coal-seam stress superposition control is solved, and the stability of the pressure relief process is improved. The method is especially suitable for a complex geological environment with mine pressure appearing caused by multi-coal-seam superposition mining.