COMPARATIVE ANALYSIS OF DIFFERENT CONTACT ELEMENT MODELS IN SEISMIC POUNDING ANALYSIS OF BRIDGES

The pounding behavior between adjacent girders is the main cause of the local damage or even collapse of bridges during an earthquake. In order to analyze the seismic pounding responses of bridges reasonably, a comparative analysis on the computational precision and application conditions of different contact element models in the seismic pounding analysis of bridges is made, based on the developed refined simulation platform FENAP. Four contact element models, including the linear spring, Kelvin-Voigt, Hertz and Jan-Hertz-damp models are lead in the FENAP, and a platform for seismic pounding analysis of structures is built. The influence of difference contact element models on the pounding responses of structures is comparatively investigated through the numerical verification and the numerical simulation of model tests under sine waves and earthquake excitations. The results indicate that the developed platform for the seismic pounding analysis of structures has a good precision and efficiency. Among the four contact element models, the Kelvin-Voigt and Jan-Hertz-damp models have higher computational accuracy and applicability, and the linear spring and Hertz models are only suitable for approximately elastic pounding cases with high restitution coefficients due to the inconsideration of the energy loss during a pounding process.