Abstract:The mechanical behaviors of the deep rock masses are different from those of the shallow rock masses. Shapes of deep have great effects on the stability of deep tunnel and supporting design. Six types of the one-line and double-line deep tunnels are studied under different stress situations by using the finite element method(FEM). The stress field and plastic zone around the tunnel are obtained. On the basis of the magnitude of the plastic zone,the optimal shape of deep tunnel is determined. It is shown from the numerical results that the quarter-circular arch model is suitable for one-line tunnel. It is found from the numerical results that the three-center arch model and the quarter-circular arch model are suitable for double-line tunnel.