Abstract: More karst cave roofs with weak mud invasion are affected by karst caves.More irregular stress concentration occurs when the roofs are under pressure，thus easily resulting in loose cracking，sliding and caving of surrounding rocks and dramatically reducing its bearing strength.Taking No.10 rail roadway of Yongju Coal Industry for instance，the physical and mechanics parameters of coal and rock samples are measured through experiments.The FLAC3D is adopted to simulate the influences of different cross-section shape and support way on the roadway stability，including the plastic zone distribution regularity and the stress distribution and deformation of surrounding rocks.Through the engineering applications and monitoring，the stability of surrounding rocks around roadway under different cross-section shape and support way is contrasted.The results indicate that the arched section jointed with rational support can improve the stress status of tunnel surrounding rocks，better control the failure area of plastic zone，and effectively lower the rock deformation.Also，it can better maintain the stability of the karst cave roof with rocks invasion.

Key words: More karst cave roof, Cross section shape, Supporting method, Numerical simulation, Stability control