Abstract:The transitional trumpet-like tunnel in Line No.3 of Rail Transit System of a given city lies at the intersection between the left line and the connection line. The cross section of the tunnel is large and has many variation points,and the top of the tunnel is close to the pile foundation of Building No.30. In order to reduce the disturbance induced by the embedded excavation on stratum and control the ground settlement,it is necessary to adopt reasonable execution techniques. Based on characteristics of the trumpet-like tunnel,spectacle and auxiliary techniques are proposed,and the elastoplastic finite element method is used to simulate the process in the construction sequences.