Uncertainties in Dynamic Soil‐Structure Interaction

Uncertainties in dynamic soil‐structure interaction are divided into two groups: Model and parameter uncertainties. Modeling uncertainties are associated with the differences between the real world phenomenon and the model, and parameter uncertainties are uncertainties in the parameters which appear in the model definition. A method to evaluate the effect of parameter uncertainties on the dynamic response of a soil‐structure system is described and illustrated. The method is based on the response surface methodology and is fully compatible with current numerical modeling codes (computer programs) used to analyze dynamic soil‐structure interaction. It consists of the development of a graduating function which approximates the true response, based on a limited number of code evaluations. The graduating function, called the response surface, is then used to evaluate the effects of uncertainties in place of the soil‐structure interaction code. The method embodies the traditional parametric or sensitivity analysis techniques and can be considered an extension of the partial derivative method or first‐order, second‐moment method to the numerical realm.