BACKFILL STABILITY ANALYSIS OF STEEP DIP MINE USING FILLING METHOD

Theoretical research method is the basic way to analyze mechanical problem. The obvious slip plane is the precondition to backfill overall stability analysis using the theoretical research method. The predecessor research results show that the interface of backfill and surrounding rock is the kind of slip plane, but the data that used to analyze the backfill stability is lack. Based on the predecessor research results, this study obtains the vertical stress differential expression in the backfill combining the inclined slip plane and ground deformation of No.2 Zone of Jinchuan Mine. Considering the sliced backfill of No. 2 Mine zone, the simply supported beam model is used to calculate the local stability of backfill. We use the numerical simulative software to analyze the maximum and minimum principal stresses of the backfill footwall, and provide the judgment of the backfill failure. The results show that the overall failure can't occur, but the local failure could occur. The upper void of two sub-levels mining leads to the deformation and failure concentrated on the corners of both sides. For the bottom void, the deformation range extends and also concentrates at corner of both sides. We should make some support in time and prevent the backfill local failure.