An Analysis Model for a Hybrid Interactive System Involving Compressible Buffer Material

摘要

In recent years, EPS (Expanded Polystyrene) geofoam is gaining worldwide recognition in construction industry either as lightweight substitution or as compressible buffer to reduce the earth pressures against retaining structures. When EPS is used behind a structure, the structure interacts with the soil via the EPS blocks giving birth to a hybrid interactive system. In this paper, a numerical model is described for the analysis of such a soil-structure-EPS interaction system. The development of the model focused on the constitutive and the interface modeling. A constitutive relation of EPS was formulated using an elasto-plastic hardening law. Recognizing the fact that there is always a thin layer of interface that participates in the interaction process, a new hybrid interface model was developed. The interface was assumed to be elasto-plastic in its behavior. The soil backfill was modeled assuming it as the elasto-plastic hardening and softening material. The developed model was validated through a numerical experiment on a rigid retaining structure.