Analytical approach to predict tunneling-induced subsurface settlement in sand considering soil arching effect

Precise prediction of the tunneling-induced subsurface settlement is of significance to assess the responses of adjacent underground structures. Tunneling in sandy soil inevitably causes uneven ground deformation and arching effect due to the role of shear stress between soil particles. The stress transfer caused by the soil arching effect could in turn affect the ground deformation. Hence, the soil arching effect should be considered in the calculation of the ground deformation. Based on the multi-arch model for tunneling-induced arching effect, this paper proposes a novel analytical approach to predict the tunneling-induced subsurface settlement on the tunnel centerline. In addition, stress-dependent modulus is adopted to consider the soil mechanical behaviors. Then, three case histories and one model test are selected to examine the applicability of the proposed methodology. The results show that the predicted curves are in good agreement with the field measurements. Hence, it is found that considering the soil arching effect is of significance to yield realistic subsurface settlement.