Multi-factor three-dimensional finite element analysis of effects of tunnel construction on adjacent pile foundation

Using the displacement control method (DCM), a three-dimensional finite element model is established to analyze the effects of tunnel construction on the adjacent pile foundation, and the effectiveness of this three-dimensional model is demonstrated through the back analysis of centrifuge tests. Based on these, parametric studies are implemented. The results of numerical simulations show that the internal force and deformation of tunneling-induced pile depend mainly on the pile-tunnel distance X _pile , pile length to tunnel depth ratio L _p /H _tun and volume loss V _L . The internal force and deformation decrease with the incense of L _p /H _tun , but the bending moment is not significantly affected. With the increase of X _pile the axial force and lateral deformation of the pile and settlement and bending moment all decrease, both the maximum bending moment and the maximum axial force of the pile increase with the increase of V _L , when V _L =3.3%, the internal force and deformation of the pile double or treble those after the consolidation of the soil, and the tunneling-induced long-term behavior of the pile should be considered in the tunnel design and construction.