It is becoming a great challenge for civil engineers to design a foundation which able to minimize the effect of an earthquake. A major earthquake produces a strong ground motion in the subsoil and surface structures supported on the soil mass will be induced to move and absorb the dynamic forces. Seismic retrofit of existing foundations is an alternative. However, the modification of this existing foundation toward earthquake resistances raises issues which are far from being totally resolved. Innovative material such as EPS is widely accepted in structural engineering due to its characteristic to absorb the dynamic force effectively. This EPS material demonstrated the practicality and has been applied for geotechnical engineering for various reasons. Based on this, a research which is related to the application of EPS in mitigating the earthquake forces, particularly for raft foundations was conducted properly in this research. The various types and thickness of EPS located beneath the raft foundation and over the soft soil are studied. A finite element program is utilized to develop the computer simulation models. Based on the results, Expended Polystyrene (EPS) Geofoam, placed beneath the raft foundation is able to produces the minimum settlements when subjected to earthquake loading rather than raft foundation modeled without EPS and increasing the density of EPS will simultaneously decrease the settlement of a foundation.
