核密度估计的桥梁结构地震易损性分析

为弥补常用桥梁地震易损性分析方法的不足,提高易损性分析的计算精度,将核密度估计法引入到桥梁结构地震易损性分析中,提出一种核密度估计的桥梁结构地震易损性分析方法(简称KDE法).以某铁路典型4跨高墩刚构-连续梁桥为工程背景,开展了该桥的地震易损性分析.以蒙特卡罗法计算结果为依据,验证了桥梁KDE法的正确性,并将KDE法与常用方法(云图法、极大似然估计法)计算结果进行对比分析.结果表明:桥梁KDE分析法弥补了常用桥梁易损性分析方法的不足,具有良好的稳定性,在满足精度要求的前提下,显著提升了桥梁地震易损性分析的计算效率;云图法的计算精度最低,建议采用KDE法开展桥梁地震易损性分析,建立的易损性曲线可评估桥梁的抗震性能.

Seismic fragility analysis of railway bridge using kernel density estimation

To overcome shortcomings and improve calculation accuracy of the common seismic fragility analysis method, the kernel density estimation method (KDE) is introduced and used to analysis the seismic fragility of bridge structures. A typical four span railway rigid frame-continuous beam bridge with high pier was taken as engineering case, and the fragility analysis of this bridge was carried out. The calculation result by using of KDE method was validated by using of Monte Carlo method, and then was compared with traditional methods (cloud method, maximum likelihood estimation method). Result shows that the KDE method could overcome the shortcomings of common fragility analysis methods of bridge and presents a good stability, and also improves the computational efficiency of seismic fragility analysis method on the premise of ensuring the accuracy. The calculation accuracy of cloud method is the lowest among of the using methods, and the KDE method was suggested to use for seismic vulnerability analysis of bridge. The seismic fragility curves could be applied to evaluate the performances of bridge seismic.