美国公路桥梁风险法确定设防船撞力评述

Comments on Vessel Collision Force Protection for American Highway Bridges Determined According to Risk Method

目前桥梁设防船撞力问题在国内深受关注,国内规范将船撞力看作偶然荷载指导桥梁设计和美国联邦公路桥梁设计规范基于风险设防船撞差距较大。通过总结美国联邦公路桥梁设计规范在确定桥梁设防船撞力时的总体思想和技术方法,在对其推荐方法——方法Ⅱ进行深入解释和推理的基础上,阐明了各关键部分的内在联系,以供国内今后桥梁船撞设防参考。

Nowadays, the issue on the vessel collision force protection for bridges is a one that has attrated much concern in China. In the relevant bridge codes in China, the vessel collision force is regarded as the accidental load and the load is often used to guide the design of bridges, which has a considerable gap to the vessel collision force protection based on the risk method in AASHTO LRFD. In this paper, the internal relations among all critical parts of the vessel collision force protection are clarified through summarization of the general considerations and technical methods in determination of the vessel collision force protection for bridges in the AASHTO LRFD and also on the basis of deep-going interpretation and reasoning of the Method II as recommended therein. It is expected that the clarification in the paper may provide reference for the vessel collision force protection for bridges in China in the future.