An analysis of the ground deformation caused by shield tunnel construction combining an elastic half-space model and stochastic medium theory

The ground movement induced by the construction of shield tunnels affects the safety of nearby underground pipes and aboveground structures. Therefore, the reliable prediction of ground movement is important. In this paper, a model describing the interaction between soil and an EPB shield used in tunnels is presented, based on the classical elastic theory of Mindlin. In this model, the changing location of the working shield is considered. The equations describing the ground deformation around the tunnel caused by the additional force on the shield working surface and the frictional force between the outer surface of the shield and the surrounding soil are derived. The ground deformation caused by ground loss due to shield tunnel construction is derived using stochastic medium theory. Finally, this model is applied to two running tunnels, and the sensitivity of the ground deformation to the calculation parameters is discussed.