PHENOMENOLOGICAL MODEL APPLIED TO INELASTIC RESPONSE OF SOIL-PILE INTERACTION SYSTEMS

摘要

A dynamic nonlinear Winkler spring model, is developed for the seismic response of deep foundations. The model utilizes the phenomenological "BWGG" model (outlined in a companion paper), and it can treat the inelastic response of both the soil and the pile. The nonlinear reaction of the soil is modeled realistically by the BWGG interaction springs and dashpots, with due consideration to effects such as: separation (gapping) of the pile or caisson from the soil, radiation damping, and loss of strength due to pore-water pressure development. The modeling of pile inelasticity is also versatile, and can treat from well-reinforced to poorly-reinforced concrete sections. The necessity for the proposed model arises from the difficulty to predict the large-amplitude dynamic response of piles up to failure. The BWGG-Winkler model is validated through the results of in-situ monotonic and dynamic pile load tests. It is further utilized to study the nonlinear soil-pile interaction under lateral monotonic loading. The results of the model are compared with the venerable Broms (1964) theory for pile lateral capacity.