Study On Characteristics Of Surface Cracks In Different Mining Height Of Loess Mining

It is necessary to study the characteristics of surface fractures in the loess area due to the increasingly serious the impact of cracks on the surface environment caused by the exploitation of underground resources in the loess area.The Dafosi coal mine is a typical representative of the western loess mining area.In this paper,this paper will study on this object.It is of great significance to discuss the research methods of surface fracture characteristics for studying the surface crack characteristics of western loess mining area.This paper takes the 40108 working face mining in Dafosi coal mine as an example.First,collecting the related information of the 40108 work surface observation station in the mining process,sorting out the relevant information,analysising the surface movement in the mining process,and summarizing the characteristics of surface fractures above the working face combined with the distribution of fractures.Secondly,The numerical simulation of 40108 working face is carried out by FLAC3D and UDEC simulation software respectively.In the simulation process,three sets of different heights are set up,and the characteristics of simulated surface fractures are summarized.Finally,the results of UDEC simulation software are more realistic and more suitable for studying the characteristics of surface fractures by comparing the two simulation results,and analysising the relative error between the data obtained by the two simulation methods and the measured data.Through the above analysis can establish the relationship between crack width and horizontal deformation.In this paper,the prediction model of crack width and crack depth is established through simulation studies because the depth of crack development is generally difficult to achieve.The width of the surface cracks which Simulated out or measured on site can be used to predict the depth of surface fractures according to the relationship between the width and the depth of the fracture.Through the above research,it is possible to provide reasonable suggestions for the safe production of the mine area and the protection of the ground building.