摘要
为研究传统均匀设计响应面法中设计变量多重相关性现象和变量相关性条件对地震易损性分析的影响,引入Nataf变换,结合基于样条变换的均匀设计响应面法,提出了一种基于改进均匀设计响应面的桥梁地震易损性分析方法。以一座多跨连续梁桥为例,基于Open Sees建立其动力有限元模型并进行非线性时程分析,考虑了墩柱、板式橡胶支座、铅芯橡胶支座和桥台四类构件的地震损伤,分别在考虑变量相关性前后、采用传统及改进均匀设计响应面法对算例桥梁地震易损性分析进行了比较。研究结果表明,考虑变量相关性后,改进均匀设计响应面法建立的响应面模型能更好地拟合结构功能极限状态函数;桥梁构件及系统在不同损伤状态下的损伤超越概率均有一定程度的降低;忽略变量相关性的影响、采用传统均匀设计响应面法均可能会高估桥梁结构在地震作用下的易损程度。
The effects of multi-correlation among design variables in the traditional uniform design-response surface methodology and correlations among structural random variables on seismic fragility analysis were studied. Introducing the Nataf transformation and combining it with the uniform design-response surface methodology based on spline transformation, an alternative method for bridge seismic fragility analysis was proposed. A multi-span reinforced concrete continuous girder bridge was taken as a case-study, its finite element model was built by using the OpenSees software and a nonlinear time-history analysis was conducted. In the study, the damages of pier, lead rubber bearing （LRB）, plate-type elastomeric bearing （PETB） and abutment were taken into account. Then, the traditional uniform design-response surface methodology and the improved one were applied to analyze the seismic fragility of the case-study bridge and their results were compared. It is concluded that the response surface established by the improved methodology can better fit the structure＇s surface limit state function. By using the improved methodology, the failure probability of bridge components and bridge system under different damage states has a certain degree of reduction. The seismic capacity of the bridge tends to be underestimated by neglecting the correlations among structural random variables and using the conventional uniform design-response surface methodology in seismic fragility analysis.
作者
李辉辉
李立峰
LI Huihui;LI Lifeng(College of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory for Wind and Bridge Engineering of Hunan Province,Changsha 410082,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2018年第22期245-254,共10页
Journal of Vibration and Shock
基金
国家自然科学基金(51278183)
贵州省交通厅科研课题(2014-122-02)
关键词
桥梁工程
地震
易损性分析
均匀设计响应面法
多重相关性
Nataf变换
变量相关性
bridge engineering
ground motion
seismic fragility analysis
uniform design-response surface methodology
multi-correlation
Nataf transformation
correlations among random variables
