Analysis on Main Control Factors of Surface Subsidence by Strip Backfill Mining with High Water Material

In order to determine main control factors of the surface subsidence caused by strip backfill mining with high water swelling material,based on the featur es of the high water swelling backfill material in Wangzhuang Mine,according to the three main factors of the overburden strata type ,backfill rate and backfill mass stren gth,the numerical simulation method was applied to the orthogonal test analysis on the surface subsidence caused by the three different levels of the three factors. The analysis results showed that backfill rate was main control factor to control surface subsidence caused by the strip backfill mining with the high water swelling material,t he backfill rate was increased from 50% to 70% and the max surface subsidence value was reduced over 50%. With a suitable backill rate ,strip backill mining could ha ve excellent control effect of the surface subsidence.