Abstract:  The displacement input condition was obtained by the sunken settlement distribution character of ground fissure. The excavation construction, lining structure section and largedisplacement of ground fissure passed vertically by a subway tunnel were simulated by the numerical calculation of DFM. The characteristics of tunnels structure and surrounding soil mass were analyzed by strata settlement, lining structure sections displacement, earth pressure on lining structure and its internal forces. The research indicates that in the condition of ground fissure movement with sunken character, settlement deformation happens mainly in the soil mass located above the ground fissure. The vertical earth pressure under the bottom of lining structure located in the soil mass above ground fissure significantly reduces. The axial stress at the end of lining structure sections increases remarkably. On the one hand, the clearance between lining structure sections can adapt the ground fissure movement and avoid the failure of lining structure, on the other hand, the lining structure sections can inhibit the deformation of strata with active ground fissure, and reduce the relative displacement adjacent lining structure sections at fissure. The measure of tunnel with lining structure section would improve the operation conditions of the ground fissure subway tunnel.

Key words: ground fissure, platform concave model, subway tunnel, numerical simulation