NONLINEAR SOIL-PILE INTERACTION-MODEL FOR DYNAMIC LATERAL MOTION

A rational dynamic soil-pile interaction model is presented. The model is developed adopting Winkler's hypothesis with a special attention to the conditions in which the strong nonlinearity is induced in the vicinity of the pile shaft under dynamic loading. It is formulated in a simple system of frequency independent mass, springs, and dashpots. Therefore, the model enables us to conduct the time-domain nonlinear analysis in a relatively simple manner. Since the model can reproduce the dynamic effects by itself, its parameters are defined from the static behavior of a soil-pile system or reasonable p-y curves developed under the static condition. With a special consideration of a gap formed at the soil-pile interface, the proposed model and procedure to define its parameters have successfully predicted the dynamic pile response observed in the field dynamic pile load tests. The nonlinear condition and dynamic condition are coupled with each other to produce the complex soil action to the pile shaft motion.