Evaluation of Kinematic Bending Moment of Piles subjected to Seismic Motions

Dynamic response of pile foundations is a very complex phenomenon consisting of kinematic and inertial interaction among soil, pile and superstructure. Piles experience kinematic bending moments caused by the soil deformations due to the passage of the seismic waves through the surrounding layered soil. These moments are increased in the interfaces ofalternating the soil layered with the different modulus. This paper presents the main results of parametrical study on single piles obtained by a 2D finite element computer code with the exiting design methods for evaluating the kinematic interaction between soil-pile subjected to the seismic excitations. The shear strain and the shear stress are evaluated by the linear equivalent method of the free field site response analyses. The results show that the kinematic bending moment at the interface is affected by the soil nonlinearity behavior and the frequency content of the seismic motion even in absence superstructure

Keywords:

soil-pile interaction , interface , kinematic bending moment , simplified methods , site response