Numerical simulation analysis of destruction characteristics of floor under goaf in seam with closed depth

Aim to the roadway under goaf in seam with closed depth have dynamic influence, the actual situation is roof rock soft stave, integrity is badly, supports and protections is difficulty. Use the relevant theoretical formula the estimated roughly damage depth of floor under coal goaf. Through the software of discrete element program to two layers is not the same thickness of floor under coal goaf mezzanine mechanical characteristics and analyzedthe stability of roadway under goaf. provides the theoretical foundation for reasonable supporting method and parameters design of the roadway under the goaf, Have a certain theoretical and practical application value.