Design of steel bridge girders against ship forecastle collisions

Abstract

A key aspect in the design of mega bridge structures across navigable waterways is to ensure bridge safety with respect to accidental ship collisions. Special attention has been paid to providing sufficient impact resistance for bridge sub-structures including piers and pylons. However, the collision design of bridge super-structures such as bridge girders is commonly neglected. In this paper, high-fidelity finite element models of a ship bow and a bridge girder are established. Numerical simulations are conducted to study the structural response of the bridge girder subjected to impact from the ship forecastle. Based on the simulation results, design considerations of bridge girders against ship forecastle collision loads are discussed. The effects of the impact location and relative structural strength are also investigated. A simple but effective strengthening method is proposed to increase the collision resistance of steel bridge girders.