Lateral dynamic response and effect of weakzone on the stiffness of full scale single piles

The determination of dynamic characteristics of soil-pile system by full-scale lateral dynamic pile load testing is an important aspect in the design of pile foundations subjected to dynamic/seismic loads. Field test results are very useful for validating existing linear/non-linear models, which are used to predict the dynamic stiffness and damping of the soil-pile system. This paper presents the results of field lateral dynamic load tests conducted at two different petrochemical complex sites in India and the measured dynamic constants of the soil-pile system. A 3D finite element analysis is performed using ABAQUS to predict the non-linear response of soil-pile system under dynamic lateral loads. The lateral stiffness estimated from the FE analysis shows good agreement with stiffness measured in the field tests. Dynamic analyses of single piles using improved Novak’s method were performed to study the effect of weak zone around the pile shaft on the lateral stiffness of the piles