基于长期监测数据的桥梁局部时变可靠度分析

本研究提出了一个基于长期监测数据的桥梁局部时变可靠度分析方法。首先，对原始监测应变数据进行预处理，滤掉电磁干扰导致的异常数据；然后，考虑到季度温度效应对监测应变数据统计特征的影响，基于年温度监测数据，采用聚类分析法，对桥梁局部位置的监测数据进行统计时间段划分，实现了统计时间段内荷载效应数据对应统计特征的提取；进而，结合结构抗力经时变化模型，对桥梁结构考虑抗力衰减的抗力时变概率分布进行分析；最后，对在役桥梁局部监测点位置进行了全期局部时变可靠度分析。通过实桥数据分析，验证了所提方法的合理性和有效性，为桥梁结构局部时变可靠度分析提供了理论基础和应用方法。

Local Time-Dependent Reliability Analysis of Bridge Girder Based on Structural Health Monitoring Data

A local time-dependent reliability analysis method of bridge girder based on structural health monitoring (SHM) data is presented in this paper. Firstly, the original monitoring strain data collected by SHM system is preprocessed to eliminate the influence of monitoring error; secondly, considering the influence of the temperature effect on the statistical distribution of the monitoring strain data, in this study, the cluster analysis method is employed to divide the statistical time period of SHM data for the local position of bridge girder based on the annual temperature monitoring data, and the extraction of the statistical characteristics of the monitoring strain data in the statistical time period is realized; then, the time-dependent probability density distribution of structural resistance of bridge girder with considering resistance attenuation is analyzed based on the time-dependent model of structural resistance; finally, the whole period time-dependent reliability of local location for the existing bridges is analyzed reasonably. Through the case study of real bridge, the rationality and effectiveness of the proposed method are verified, which provides the theoretical basis and application method for the local time-dependent reliability analysis of bridge girder.