大跨连续刚构桥施工期间地震风险分析

根据以往地震后桥梁震害调查情况及连续刚构桥的施工特点,给出了施工期间不同等级地震作用下可能发生的风险事件。依据桥梁的抗震设防要求、施工特点以及结构性能,推断出地震发生的概率及其等级。针对施工期间地震发生时可能造成的损失,从经济损失、人员伤亡、工期延误、环境影响四个方面进行了考虑。然后根据风险发生概率及其对应的损失确定风险级别,并做出相应的决策。最后,应用所建立的分析方法对北山连续刚构桥进行了施工期间地震风险的分析和评价。

Analysis of Seismic Risk for Long-span Continuous Rigid-frame Bridges during Construction

The possible risk events of long-span continuous rigid-frame bridges under different earthquake levels during construction were identified according to the investigation of the damage in the past earthquakes  and the construction features. Based on the requirements for earthquake resistance, characteristics of construction and structural performance of the bridge, the level and probability of earthquake were deduced for risk analysis. The losses caused by earthquake during construction were considered from the aspects of economic loss, casualties, construction delay and environmental impact. The risk level was determined by the probability and its risk costs, and the related decision making was done. A case study was carried out for Beishan Bridge by using the established analytical method at last.