近期典型桥梁事故回顾、分析与启示

对1813~2018年期间的584起桥梁事故进行分析，将桥梁倒塌原因分为施工、自然灾害、设计、意外荷载、耐久性等5类。各原因在倒塌事故中所占比例分别为42.1%、30.0%、11.6%、12.7%、3.6%。除自然灾害外，设计施工不合理为主要原因，而事故发生大多是多种原因综合的结果。以近几年9起典型桥梁倒塌事故为例，分析比较各种倒塌桥梁的主要破坏模式，得到以下启示：①国内大部分梁桥上部结构的平面外位移约束构造不足，在任何一个平面内都不应该是可变体系是国内桥梁设计施工中需要注意的问题；②在应用新工艺、新结构和拆除旧桥时，应加强各种施工工况下的验算；③建议加强桥梁巡查，预防和禁止汽车超载以及桥梁附近大规模堆载；④应注重桥梁结构尤其是斜拉桥和悬索桥等特大桥梁的日常养护管理，当养护力量不足时，尽量选择养护要求较低的桥型。

Review,Analysis, and Insights on Recent Typical Bridge Accidents

Based on an analysis of 584 bridge accidents from 1813 to 2018, the causes of bridge collapse were divided into five categories, construction, natural disasters, design, accidental load, and durability, and the proportion for each category is 42.1%, 30.0%, 11.6%, 12.7%, and 3.6%, respectively. In addition to natural disasters, unreasonable designs and constructions are the main causes of bridge accidents, with a majority of these accidents resulting from a combination of multiple causes. In this study, nine typical bridge collapse accidents in recent years were considered as examples to analyze and compare the main failure modes of various collapsed bridges. Based on this analysis, the following insights can be obtained:First, a majority of the superstructures of girder bridges in China are insufficient, out-of-plane displacement restraint structures. However, these structures should be stable in all planes. Hence, this problem should be addressed during the design and construction of domestic bridges. Second, the verification calculations for various constructions involving new technologies, new structures, or dismantling of old bridges should be strengthened. Third, it is suggested that bridge inspections should be improved to prevent vehicle overloading and large-scale surcharges near bridges. Fourth, additional attention should be paid to the daily maintenance and management of bridge structures, especially cable-stayed bridges, suspension bridges, and other large bridges. When maintenance services are insufficient, bridges with lower maintenance requirements are recommended.