Research on Space Effect of Face Length of Full-mechanized Caving Mining with Large Mining Height

For obtaining rational mining face length of full-mechanized caving mining with large mining height,this paper applied numerical simulation to researching structure of overlying strata and stress distribution of surrounding rock under different face lengths.Result showed that with face length increased,the influence range of advanced abutment pressure increased,pressure peak was further away from coal wall,height of stress arch increased and underground pressure behavior was stronger.When the face length increased to some value,location and value of abutment pressure and height of stress arch would be constant.The results are important for designing rational face length of full-mechanized caving mining with large mining height.