Effects of soil non linearity on bending moments in piles due to seismic kinematic interaction

This paper presents the results of different types of dynamic numerical analysis performed to evaluate kinematic bending moments developed during earthquakes in a single pile embedded in a two layer subsoil profile. A quasi 3D finite element computer program has been used for the analyses performed in the time domain. The pile has been considered as an elastic beam, while the soils have been modelled using the equivalent linear constitutive model with strain-dependent modulus and damping, using typical relationships among these parameters and shear strain. The results of these analyses have been compared with those obtained with linear analyses. The study shows the relevance of soil non linearity on the bending moments induced by seismic kinematic interaction. The comparison between results shows that the distribution of bending moments is also affected by the seismic input