Breaking mechanism of overlying strata under thick unconsolidated layers and integrated grouting reinforcement technology for wind oxidation zone

With the method of physical simulation,theoretical analysis and field measurement,in the case of different overburden structures,this study investigates the law of overlying strata movement,relationship between support and surrounding rock under the load transfer of thick loose aquifer and integrated grouting reinforcement technology for wind oxidation zone. The results show that when there is only a key stratum in stope overlying strata,with the process of coal mining,in unconsolidated aquifer load transfer function,overlying strata large range collapse sink acting on the support below,and support force is bigger,and it is easy to occur support crushing accidents. When stope overlying strata has two key strata,its collapse to high key stratum form a ‘voussoir beam’ structure,the structure can make the transfer of aquifer overlying alluvium pressure shift away from stope support,and it improves the hydraulic support force status. Based on this,it takes 1512(3) working face of Gubei Mine as an example,according to the geological conditions of loose aquifer single key stratum,the method of J type horizontal wing branch hole is applied to reinforce the wind oxidation zone,aim to artificially build a high key stratum,this slows down the stress behavior when the work- ing face is pressed,and the working face achieves the goal of safe mining,which verifies the rationality of the research results.