关键词: 数值模拟法, 采空区, 隧道, 安全距离, 稳定性

Abstract: The stability of spatial relationships of Chunchunzhai Tunnel over the abandoned mines in G3612 Pingdingshan to Yichang Expressway Yichang section is presented in this paper as a case history. A numerical model is established by using FLAC3D software to simulate the displacement, stress, and plastic zone changes of the tunnel roof at a distance of one to three times of the tunnel diameter from the abandoned mined area. The study showed that in the transverse direction, when the transverse distance between the tunnel and the abandoned mine is greater than two times the width of the abandoned mine shaft, the impact of the hollowed shaft on the tunnel is relatively small. Vertically, when the distance between the tunnel arch and the abandoned mine is not less than 24m (twice the tunnel diameter), there is no connection between the hollow shaft and the plastic failure zone of the tunnel. The impact of the abandoned mine area on the tunnel is relatively small; This indicates that the distance between Chunqiu Village Tunnel and the overlying abandoned mined area in the horizontal direction is less than twice the width of the shaft, and in the vertical direction is less than twice the diameter of the tunnel, which belongs to the area with greater impact from the abandoned mine area. 

Key words: Numerical Simulation Method, Goaf, Tunnel, Safe Distance, Stability