Dynamic Bearing Characters and Numerical Analysis for Top Coal Caving Hydraulic Supports in Mindong No.1 Mine

The KJ216-F pressure monitoring system is used to monitor the top coal caving working resistance before and after prop at I01163 upper 01 face of Mindong Mine. The FLAC^3D numerical simulation software is used to simulate the mining face’s actual situation to conduct the further research in dynamic bearing characters. The results show that the difference value of the two props fluctuated in different areas of the mining face in the nearly horizontal mining face. This phenomenon can be explained as the various fragmentation degrees caused by the abutment pressure in different areas. Under different top coal conditions, the difference value of the two props changed when the top coal’s rigidity changed. When the top coal’s rigidity is low, the working resistance of the two props is low and well-distributed. when the top coal’s rigidity is moderate, the difference value of the two props is large and the top coal above the support is divided into three zones obviously. The difference value of the two props can be utilized to forecast the distribution of the cracked top coal.