Study On The Relationship Between Surrounding Rock And Support Of Thin Bedrock In Thick Unconsolidated Aquifer

In this paper,aim at the special geological condition of thin bedrock mining under thick unconsolidated aquifer,the methods of theoretical analysis,similar simulation,numerical simulation and field measurement are used.Combining Zhangbei 1210（3）to conduct comprehensive research between support and surrounding rock in mining face under thick unconsolidated aquifers,and ultimately determine the type of stent.The results show that:（1）The confined aquifer has above the load transfer function,analyzed the load transfer quantity for confined aquifer:p=γ_wH’+k(γH+γ_sath-γ_wH’);Thin bedrock roof can establish elastic plate model,by using the elastic thin plate theory to explain the "O-X" roof breaking and the calculation of roof breaking step.（2）The simulation results show that the upper part of the aquifer will be transferred to the goaf and the fracture angle of the coal seam will decrease and then increase with the advancing of the working face.（3）Zhangbei coal mine 1210（3）UDEC model results establish working face specific geological conditions show that the gob roof caving is not before,in front of the working face coal wall and support the interaction of bearing structure;gob span backward,goaf,coal wall bracket and the interaction of the support structure,should be force transfer.The existence of the key layer can effectively reduce the downward transfer of the overlying load,which can relieve the stress of the mining area.（4）Data from Huainan mining area of Zhangbei coal mine 1210（3）working face shows that theoretical design results support resistance is small,the working resistance of support should be improved.