Influencing Factors’ Analysis of Disturbance Degree of Key Stratum Based on the Response Surface Method

The key stratum controls the activities of overlying strata or whole up to surface, which is one important research objects in coal seam mining. Based on analysis several geological factors affecting stratum, definition “disturbance degree stratum” (KSDD) was proposed. And, KSDD quantified by value among 0 10. Through response surface method, experiments three (mining height, buried depth, and interlayer spacing) with different lithology types (soft, medium, hard) between are signed. each scheme calculated developed calculation system. regression models established. single influence interactive influences studied. results show that following. (1) Mining height depth positively correlated KSDD, spacing negatively KSDD. However, when exceeds 30 m, change tends be gentle. (2) not only affected a factor but also interaction various factors. With increase burial decrease impact mining more severe. (3) order as follows: > depth. (4) Although interact other, proportional coefficient. According above results, based five mines, variation laws actual situation analysed. further verify experimental rules, provide certain reference theoretical basis for design backfilling parameters management roof.