Dynamic Response of Piles ─ Case Studies in India

Dynamic behavior of piles is strongly affected by the variation in the soil stiffness with depth and the interaction between the soil and the pile. The dynamic characteristics of the piles can be determined by using simple lumped mass models to complex finite element modeling. There is a need for experimental research, in particular large-scale field tests, to validate existing linear/nonlinear models, which are used to predict the dynamic stiffness and damping of the soil-pile system. 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 loads. 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 three-dimensional finite element analysis is performed using ABAQUS to predict the nonlinear response of the soil-pile system under dynamic lateral loads. The lateral stiffness estimated from the FE analysis shows good agreement with stiffness measured from field tests. The paper also discusses on the dynamic analysis and design of Primary Air (PA) and Force-Draft (FD) fan foundations of a thermal power plant using finite-element analysis