EVALUATING RADIATION DAMPING OF SHALLOW FOUNDATIONS ON NONLINEAR SOIL MEDIUM FOR SOIL-STRUCTURE INTERACTION ANALYSIS OF BRIDGES

The paper evaluates the radiation damping associated with shallow foundations sitting on linear or nonlinear soil medium. The study is motivated by the need to develop a macroscopic foundation model that can realistically capture the nonlinear behavior and energy dissipation mechanism of shallow foundations. Such model is essential to simulate the complex behavior of bridges sitting on flexible foundations due to soil-structure interaction effects. In this study, the dynamic response of an infinitely long strip foundation resting on an elastic and inelastic half-space is investigated. The study revealed responses ’ strong dependency on amplitude and frequency of the motion. It also found that the radiation damping of nonlinear soil medium is significantly lower than the elastic soil counterpart, which in turn affects the bridge response