EFFECT OF DIFFERENT TYPE OF FOUNDATION MODELING ON PREDICTED RESPONSE OF SOIL-STRUCTURE SYSTEMS

The effect of two types of foundation modeling on predicted response of structures is investigated. The first type of modeling includes a traditional approach in which the radiation soil damper and the nonlinear soil spring act in parallel. The second model is based on a newer approach in which the yielding part of the soil is represented by a nonlinear spring that is connected to the linear soil spring-damper parallel couple in series. The latter case, which is a more rational model for the soil, has attracted more attention in recent decade and is considered here as the benchmark model. The effect of using these models on structural responses was examined against each other using nonlinear dynamic analysis. It is seen that for squat buildings using the traditional model yields to somehow reasonable approximations for structural responses while the accuracy of sway and rocking foundation motions is not preserved. In slender systems, using such models, the predictions for structural responses are conservative and the foundation deformations are notably underestimated