Control mechanism and application of large deformation of dynamic pressure roadway of fully mechanized top-coal caving face

Based on the distribution law of two types of slip surface and the deformation characteristics of dynamic pressure roadway in fully mechanized top-coal caving face, the mechanical model for microstructure of anchor bolts, Class I slip surface and Class II slip surface are studied. The reconstruction mechanisms of level-one and level-two anchors are obtained. The support idea of "top and bottom to help control the sides" is put forward, and the evolution of the graphic is deduced. The roadway deformations and failure laws under three different support programs of fully mechanized top-coal caving face are studied through numerical simulation of FLAC3D. The results show that compared with option I, roadway damage depth and plastic zone development unit based on option II and III are reduced by 44.4% and 66.7%, and the deformations of two sides are reduced by 51.4% and 68.6%, and 50% and 68.9% during roadway excavation and mining. The industrial tests on mining roadway along the bottom and the top of tunneling by the new support idea are developed on the fully mechanized top-coal caving face. The roadway deformation by the proposed method can be effectively controlled, and meets the requirements of production safety. The results have important guidance to the surrounding rock control of caving mining roadway under similar engineering geological conditions.