There are two main reasons for the old bridge collapse. One is flood and another is collision with ship. Nowadays ships though bridge span are increasing bigger and faster, so they would not be adapted to the active criterion. It has to be judge again. The force of ship collision and the resistance of pier are calculated according to the mass, velocity and the amount of these ships to decide the reconstruction of the bridge or the establishment of anti- collision facilities. This paper introduces the establishment of passive and active anti-collision facilities.%老桥坍塌，有两个主要原因，一是洪水，二是是被船撞塌。广东九江大桥被船撞塌，是我国被撞塌的桥梁中最大的一座，中小桥梁被撞塌的也有不少。桥梁跨过航线，就有机会被船撞，通过桥下的船越来越多、越来越大、越来越快。而建桥时采用的许多规范已经不适应现在的要求。因此需要进行相应的评估。按照新的通航船舶的质量（排水量等）、航速和通过量（频率），计算出撞击力和估算的撞击概率，决定是拆掉重建还是增加防撞设施。防撞设施有主动的和被动的两大类：主动的有：涂上红白漆450斜纹，显示通航孔、非通航孔和实时净空；灯标、航标和其中有一个雾天黄灯；进入禁航区的警号；航行服务系统（包括雷达和甚高频电话的VTS系统）等。被动的防撞设施亦称结构防撞设施。分为间接式和直接式，又各有多种。其中，我国的柔性粘滞耗能防撞装置就是一种直接式结构防撞设施，它能降低船撞力一半左右，在保护桥的同时也保护船和环境，从而有助于创建和谐社会。
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