Performance Evaluation of Existing Bridge Fenders for Ship Impact

Abstract

Bridge fender systems are used to guide vessels through navigational channels under bridges. They appear to be an attractive and inexpensive solution for protecting the integrity of bridge piers. However, until now the fenders have not been designed to withstand any specific lateral design force. Thus, their existing impact capacity is unknown. The paper presents results of the research project funded by the Florida Department of Transportation aimed at evaluating the crashworthiness of the system and developing possible retrofit recommendations. The research efforts concentrated on computational analysis of a Jumbo Hopper barge impacting a commonly constructed fender. LS-DYNA, a nonlinear explicit dynamic finite-element code, was used for analysis. Various initial velocities and impact angles were used to represent possible collision conditions. Computational analyses were adopted to assess the crashworthiness performance of the constructed fender system and to identify its weakest components for possible retrofit. It appears that such retrofits could further improve the energy absorbing capabilities of existing bridge fenders.