断索导致的斜拉桥结构易损性分析

Vulnerability Analysis of Cable-stayed Bridge Due to Cable Failures

提出从损伤场景对结构性能的影响程度和损伤场景占结构体系总体规模的比例两个参数进行结构易损性分析的方法,并以斜拉桥结构体系为对象,分别以主梁最小屈曲安全系数和最大应力安全系数作为结构性能参数,对不同位置拉索断裂的损伤场景进行了易损性分析.以某斜拉桥为例,采用提出的易损性分析方法,从众多的拉索断裂损伤场景中得到了造成后果尽可能严重而自身占结构比例尽可能低的易损场景.分析结果明确了结构对不同位置拉索断裂的敏感性,可以作为结构健康监测中监测内容选取以及传感器布设的参考依据.

This paper presents a bi-parameters structural vulnerability analysis method with the damage consequence and the relative magnitude of the damage scenarios to the structural system as two parameters.The proposed method was applied to the study of the cable-stayed bridge vulnerability to cable failure scenarios by taking the minimum stability factor and the maximum stress safety factor of the main girder as the structural performance measurements.A case study was made of the cable-stayed bridge to illustrate the proposed method.The vulnerable scenarios with a higher consequence but lower magnitude were found.The simulation revealed the structural sensitivity to cable failure scenarios.The analysis results can thus be referenced for designing the structural members to be monitored and the sensor allocation of a structural monitoring system.