3RD INTERNATIONAL CONGRESS ON TECHNOLOGY - ENGINEERING & SCIENCE - Kuala Lumpur - Malaysia (2017-02-09)

The Effect Of Local Uplifting Of Elastic Perfectly Plastic Soil Based Foundation On Seismic Response Of The Structure
In this work, seismic response of a structure founded on elastic-plastic soil was analyzed by taking into account soil-structure interaction. The structure was modeled by an equivalent flexible beam mounted on a rigid foundation that lays down on soil assumed to undergo elastic perfectly plastic deformation. The foundation was also assumed to undergo local uplifting with rotations that remain sufficiently small. The soil action was modeled by Saint-Venant’s units mounted in parallel and distributed over the entire width of the foundation. Use of spring elements enabled to depict the initial elastic soil deformation while allowing gradual transition from soil elastic strain range to plastic range. A system of non-linear differential equations governing the coupled problem was derived by writing the equilibrium conditions for the foundation-structure system where the structure was idealized as a single-degree-of-freedom oscillator. Then, these equations were integrated by using the Matlab command ode15s. The response of the structure was studied after that as function of the chosen soil model. It was found that the elastic perfectly plastic analysis provided smaller rotational angles and tip horizontal displacement than those resulting from a purely elastic analysis of the coupled problem.
Nadia EL ABBAS, Abdellatif Khamlichi, Mohammed Bezzazi