多种环境因素下预应力混凝土连续梁桥时变损伤特征及性能演变研究

In the short-term and long-term effect of the factors such as temperature and humidity, atmospheric environment and vehicle load, the dynamic characteristics of the prestressed continuous bridge is varying with time and the real damage on the deck is covered, thus, the damage detection is often ineffective. The multiple environmental factors also cause the evolution and deterioration of the bridges, the damage phenomenon includes chloride profiles, carbonation, fatigue, alkali-aggregate reaction and long-term deflection. The research on integrating the health monitoring, durability analysis and bearing capacity assessment is necessary, and the extraction of the time-varying dynamic characteristics and the refined simulation for performance evolution under multiple environmental factors are the important problems. The analytical solution system for multi-span continuous beam bridge is studied first, and this provides a theoretical platform for the damage detection and bearing capacity assessment under multiple environmental factors. Then, based on the durability test and SHM technology, numerical analysis and finite element fine simulation, the research includes the environmental factors separation method based on cointegration theory and error correction model, the performance evolution simulation based on dynamic path probability mode, and the bearing capacity assessment based on statistic damage detection and fine finite element simulation. The research results of this project will enhance the level and efficiency of bridge performance evaluation, and to promote the research and application of the relevant domain with important theoretical and engineering value.

在温湿度、大气环境及车辆荷载等因素的短期及长期作用下，预应力混凝土连续梁桥的动力特征具有时变性，往往容易掩盖其真实的损伤状况，产生损伤识别误判。同时多环境因素也造成了桥梁产生诸如氯离子侵蚀、碳化、疲劳、长期下挠等材料和结构的性能演变和劣化。如何将健康监测、耐久性分析及承载力评定密切结合，发展多环境因素下的连续梁桥时变动力特征的准确提取及性能演变的精细化模拟，是亟需解决的问题。本项目首先研究多跨连续梁桥的解析解体系，为多因素下预应力连续梁桥的损伤识别及承载力分析提供理论平台，之后基于耐久性试验及监测技术、数值分析及有限元精细仿真等手段，深入研究基于协整理论和误差修正模型的多环境因素分离方法、基于动态概率路径的多环境因素桥梁性能演变过程模拟以及基于统计损伤识别和精细化有限元仿真的承载力评定方法。本项目研究成果将提高桥梁性能评价的水平及效率，对推动相关方向的研究与应用具有重要的理论及工程意义。

在温湿度、大气环境及车辆荷载等因素的短期及长期作用下，预应力混凝土连续梁桥的动力特征具有时变性，往往容易掩盖其真实的损伤状况，产生损伤识别误判。同时多环境因素也造成了桥梁产生诸如氯离子侵蚀、碳化、疲劳、长期下挠等材料和结构的性能演变和劣化。如何将健康监测、耐久性分析及承载力评定密切结合，发展多环境因素下的连续梁桥时变动力特征的准确提取及性能演变的精细化模拟，是亟需解决的问题。本项目首先研究多跨连续梁桥的解析解体系，为多因素下预应力连续梁桥的损伤识别及承载力分析提供理论平台，之后基于耐久性试验及监测技术、数值分析及有限元精细仿真等手段，深入研究基于协整理论和误差修正模型的多环境因素分离方法、基于动态概率路径的考虑疲劳、碳化和锈蚀等多环境因素桥梁性能演变过程模拟以及基于统计损伤识别和精细化有限元仿真的承载力评定方法。本项目研究成果将提高桥梁性能评价的水平及效率，对推动相关方向的研究与应用具有重要的理论及工程意义。