Seismic Response of End-Bearing Piles

A very simple analysis of dynamic soil-pile-supported mass interaction is presented as an aid to understanding pile foundations behaviour during earthquakes. The equilibrium equations of the soil and pile movements during seismic motions are established and the response of the soil-pile system is obtained as a function of the existing frequency; for simplicity the analysis was based on Winkler's model although the same procedure can be applied using a more refined model. The effect of the supported mass is studied, the natural frequency of the system is obtained, and some practical design considerations are presented. A method for considering group effects is also presented.