Analysis And Study Responses Of Existing Tunnel During Shield Advancing

With the development of the transportation technical,and because of the advantage of tunnel excavating,shield tunneling are widely used in subway construction.And at the same time more demands are brought for its transportation ability.So parallel tunnels are used increasingly in building Metro engineering.In recent years,subway construction was developed in Tianjin,studing the influence of parallel tunnel on short distance for Tianjin soil type is also useful.Base on the Tianjin NO.1 subway conditions, we have set up the FEM modle by using finite element analysis software ABAQUS.The nonlinearity of soil material and the structure void of shield and the interaction between the gasket and soil also been taken into account in this 3D model. This paper is carried out to simulate the single line excavating first, and conclude the settlement of the section of the soil,then those real engineering data of NO.1 subway line is used to prove the rationality of the FEM parameter of this model. Through contrast, the result of FEM simulate is coincide to the real engineering data.Secondly based on the Tianjin NO.2 subway project,excavat the second tunnel on short distance after the first one finished,studing the settlement and stress of the latter tunnel and soil caused by the construction of the new tunnel,then conclude the laws of influence on the old tunnel and ground face settlement.The last conclude the problems caused by short distance excavating and forced the control measures.The results may apply to the Tianjin parallel tunnels on short distance subway construction.