Abstract: In this paper, the FLAC3D software is applied firstly to simulate the deformation and stress distribution of the winch room at level of -648 m, considering the serious floor heave and characteristics of tensile-shear damage in Gubei Coal Mine of Huainan. From simulation results, obvious stress concentration is found at variable cross-sections and corners. The results also demonstrate that the fundamental reason of floor heave is caused by base shear slip and floor fracture uplift under high in-situ stress. Based on the theory of stepwise supporting, the supporting method for winch room floor is optimized. Moreover, the surface and deep displacement, anchor cable tensile force and the internal stress of concrete foundation are monitored. From the monitoring results, we can see that roadway floor heave occurs and the cross section of roadway tends to roundness with the original support method; the grouting tube and the base beam can well resist base shear slip; floor deformation is influenced greatly by in-situ stress orientation, and the newly combined supporting method can not only control floor deformation, but also effectively enhance the stabilities of roadway walls and concrete foundation of winch room.

Key words: floor heave, stress concentration, displacement monitoring, anchor cable tensile force, concrete stress