【摘要】 首先概述公路桥梁系统地震风险评估的基本流程及研究现状。然后以汶川地区公路交通网络为背景,分析该地区地震活动性参数及断层特征;依据震级-频度关系,计算不同震级地震的年平均发生概率,依此抽样生成一系列的地震样本。根据不同桥型的重建费用和不同损伤状态下的损失比,以及既往研究中所建立的经验型易损性模型,对汶川地区公路桥梁系统在地震作用下的经济损失进行评估。在计算得到各地震样本事件下公路桥梁系统的地震损失期望和方差后,结合地震样本年平均发生概率,建立汶川地区公路桥梁系统的地震风险曲线,该曲线可为该地区交通系统整体规划和修复决策提供依据。更多还原

【Abstract】 The basic flowchart and state-of-the-art of the seismic risk assessment for a highway bridge system were firstly summarized.Under the background of the highway transportation network in the Wenchuan region,the seismic activity parameters and fault characteristics were analyzed.Based on the magnitude-frequency relationship,annual average probabilities of occurrence for different magnitude earthquakes were calculated and a set of earthquake scenarios were produced.Reconstruction cost of bridges for different categories and damage ratio to different damage states were determined.Based on the fragility functions for different categorical bridges in the previous studies,the mean value and variance of seismic loss of the highway bridge system for each scenario were estimated.Combined with the annual average probabilities of occurrence to earthquake scenarios,risk curve of system loss was generated.The curve can be used as an evidence for overall planning and retrofit strategy of the transportation system in this region.更多还原