Research On The Overburden Deformation And Its Damage Regular Under The Conditions Of A Large Mining Depth

In recent years,with the development of our national economy,many infrastructions projects accelerating to put into practice,mineral resources had been mined heavly,especially colliery mined more extensively. many shallow coal mining mineral resources exhausted face. With the further development of the economy,more mineral resources are needed increasingly. The mining depth becomes more and more deep.Therefore the study of large embedded depth is of theoretical and practical significance. Along with the progress of computer technology numerical calculation method is continuously developed and widely used in scientific research and engineering practice,including tunneling excavating,mining engineering and underground engineering,etc. Its advantage is to replace expensive and time-consuming test,to study the problem by numerical simulation.This topic is taking XinBao expressway in the coal mine goafs section as experiment's research base, adopting similar material simulation experiment and numerical simulation methods discussed the surface deformation,the goaf fracture zones development height and the development rule of overburden rock damage under the condition of different buried depth and different thickness when the circumstance of other mining conditions invariable, The main results are as follows:1.According to the results of the experiment similar material simulation, discussed the overburden strata movement and ground surface deformation law after coal mining, analysed the overburden rock fracture goaf vertical and horizontal fracture distribution characteristics. and statisticed the fracture rate.2.According to the results of the experiment similar material simulation, discussed the rock fracture zone height, mining process of overburden rock fracture upwards, mining development after the hulking coefficient of overburden rock from below, overburden strata in the output from upwards in order.3.According to the numerical calculation results, this paper discusses the different circumstances in the surface deformation, with the movement of the increase of mining depth, the surface movement range of basin gradually increasing, the surface subsidence in maximum. In large mining depth, the surface movement under the condition of deep basin with mining to decreases. The surface subsidence by linear relationship with thick.4.According to the numerical calculation results, the comprehensive consideration of the mining depth, by introducing the factors affecting the thickness of mining depth mining thick, when the ratio of depth mining and thickness mining more than 300 ,the effect of coal mining activities on the surface is very small, when the ratio of depth mining and thickness mining more than 400, no influence on surface activity.5.According to the numerical calculation results, through the level of stress and tension strength of rock overburden rock fracture zones get height, research shows that the development of mining depth, under the condition of the increase of mining depth, with rock fracture zone, highly decrease gradually.