Study On The Application Of Different Methods To Determine The Influence Range Of Coal Mining Subsidence

Coal mining subsidence is the destruction of the original stress balance of the overlying rock strata in the upper part of the mined area after the underground coal mineral resources have been artificially mined.The rock strata is deformed and damaged such as bending,fracture,and falling.The deformation of the formation is transmitted upwards to the surface.An elliptical or irregular subsidence basin larger than the mined-out area is formed directly above and around the goaf.As underground coal resources continue to be mined,the area of coal mining subsidence will continue to expand.The coal mining subsidence area will have a greater impact and damage to the mining area and the surrounding industry and agriculture,the lives of the residents and the ecological environment;it will cause damage to the ground roads,buildings,farmland and other ground attachments,and also cause Other natural disasters.In order to achieve sustainable social and economic development while coal mining,it is necessary to solve the problem of subsidence areas.The study of methods for determining the range of influence of coal mining subsidence can more effectively clarify the laws of surface rock deformation,which is very useful for regional overall planning and design,land acquisition and reclamation,sustainable development of mines,safe production,and social and economic benefits.Important practical guiding significance.This article takes the goaf of a coal mine in Gaoping,Jincheng City as the research object,and collects the surface rock movement data and borehole measurement data of adjacent mining areas.First,analyze and summarize the geological environment data of the study area,and determine the goaf area based on the comprehensive geophysical data on the ground.Based on the scope,according to the results of the surface survey,the characteristics of the deformation and movement of the overlying strata of the underground goaf and the general law of surface deformation caused by coal mining subsidence are summarized;the probability integration method based on mathematical methods and the numerical simulation based on mechanical properties are used to compare A comparative analysis of the impact range of coal mining subsidence,The results show:(1)The impact range of coal mining subsidence is obviously affected by topographical fluctuations.In areas with large elevations,steep slopes,and thicker loose overburdens,the diffusion angle of the impact of ground subsidence has become significantly larger,and the impact of coal mining subsidence is relatively large;at the same time,The greater the goaf span,the greater the upward displacement of the goaf subsidence;if there are two adjacent goaf areas,the coal mining subsidence will form a superimposed effect on the surface,which will aggravate the surface subsidence and deformation..(2)The probability integral method based on mathematical theory and the numerical simulation based on mechanical properties have practical application significance in determining the scope of coal mining subsidence.The two methods have strong commonality in the development law of coal mining subsidence,but in the calculation results There are also certain differences.Based on the two methods of determining the scope of coal mining subsidence,the calculated coal mining subsidence impact contours are all approximately elliptical,with the largest displacement in the center of the goaf,and it spreads to the surroundings with the goaf as the center..(3)When the probability integral method based on mathematical theory determines the coal mining subsidence range,the calculated coal mining subsidence deformation is the largest directly above the goaf,and attenuates rapidly when spreading outward,and reaches the 0mm boundary in a short horizontal distance;The maximum subsidence calculated by this method is relatively large.In this case,the maximum subsidence scale of the center surface of the goaf area in this case can reach several meters,and extreme subsidence is expected to a certain extent;but for the deformation of the house,the coal mining surface calculated by this method The correlation between the settlement value and the cracks in the house has a certain gap compared with the actual situation.From the perspective of this example,the calculation result range is slightly smaller than the actual surface deformation range.(4)When the numerical simulation method based on mechanical properties determines the coal mining subsidence range,the calculated coal mining subsidence deformation is also relatively large inside,but it attenuates approximately uniformly when spreading outwards,and the attenuation is slower.The maximum value calculated by this method is relatively small,The maximum subsidence scale of the surface in the center of the mined-out area in this case is only tens of millimeters(extreme conditions such as collapse pits or tensile cracks are not considered),and this value is consistent with the subsidence data of the subsided basin actually investigated in this work;at the same time,for For the influence of ground construction,the calculation result is closer to reality than the probability integral method.(5)Taking the example of this article as an example,under the condition of ensuring the accuracy and reliability of the calculation parameters,the probability integral method based on mathematical theory is suitable for calculating and predicting the inner subsidence and deformation of the goaf,which can calculate the collapse and deformation under extreme conditions;based on mechanics The nature of the numerical simulation method is suitable for calculating and predicting the external subsidence and deformation of the goaf,especially the influence of subsidence on the deformation of buildings.