Influence of tunneling on deflection of adjacent piles considering shearing deformation of foundation and 3D effects of lateral soils beside piles

At present, the studies on pile deformation caused by tunneling are generally based on the Winkler foundation model. Few investigations are conducted on the shearing deformation of foundation and the 3D effects of lateral soils beside piles. Based on the Pasternak foundation model, firstly, the analytical solution of tunnel-pile interaction is derived. It reflects the effects of shearing deformation of foundation, but the 3D effects of lateral soils beside the piles are not considered. On this basis, the equivalent concentrated forces are supplied to the pile through the shear layer considering the 3D effects of lateral soils beside the piles. The expressions for lateral displacements and bending moments of pile groups are derived. The calculated results are compared with those without consideration of 3D effects of lateral soils beside the piles. It is found that the results considering effects of lateral soils beside the piles are closer to the monitoring data and centrifuge test data. In addition, the influencing factors of pile groups are investigated. The results show that the effects of soil shearing deformation on the pile deformation should not be ignored. With the decrease of foundation shear modulus, the lateral displacements of piles decrease. With the increase of the pile diameter, pile displacements decrease but the bending moments increase. The maximum lateral displacements and bending moments of piles increase with the decrease of pile-tunnel distance.