Abstract：Based on the key layer theory，the falling process of the overlying rocks in fully-mechanized top-coal caving stope is simulated using the RFPA¢2000 software. The dynamic distribution patterns of the caving of the overlaying rocks and the abutment pressure in surrounding rocks are analyzed. The distribution of the abutment pressure in the goaf is obtained by numerical simulation for the first time. According to the calculated results，the cracked rocks in the goaf can be divided into three areas，namely，natural accumulation area，structure supporting area and steady compaction area. The findings are of important value for describing the compaction state and analyzing the seepage features of the cracked rock in the goaf.
