复杂气象条件下无现场监测数据的箱型梁桥温度效应分析与评估

温度效应是导致桥梁病害和性能退化严重的重要因素。目前，桥梁温度效应分析不能考虑复杂多变的天气情况且严重依赖现场监测数据，难以满足大多数桥梁的工程分析需求。本项目以温度效应显著的箱梁桥为研究对象，针对覆盖桥梁数量最多的城市和郊区场地，开展复杂气象条件下无现场监测数据的桥梁温度效应分析与评估方法研究。首先，研究场地气象参数的时-空多尺度特性和复杂气象下桥梁热辐射环境的定量计算，提出基于气象共享数据预测桥址场地气象的方法；其次，提出考虑风局部特性和完全热平衡的有限元瞬态热-辐射耦合分析方法，实现复杂气象条件下桥梁温度场的精细数值分析；然后，基于三维温度荷载和静力响应的瞬态及完整年历程分析，开展箱梁桥温度效应瞬态与年尺度的评估方法研究；最后，对研究方法进行材料、构件和缩尺模型试验研究，通过实际箱梁桥开展工程验证与应用。本项目对桥梁温度效应分析与评估技术具有重要的理论研究意义和重大工程应用前景。

Temperature effect is the main factor resulting in damages and performance degeneration on bridges. At present, the methods for bridge temperature effect analysis and assessment cannot be implemented for the complex and changeable weather, also, they highly rely on the field measurements, which make them difficult to meet the engineering analysis requirements of the most of bridges. Taking the box girder bridges (the type of bridge with significant temperature effects) as the research objects and focusing on the urban and suburban sites (the types of service environment covering the largest number of bridges), this project develops a new temperature effect analysis method for bridge which is suitable for complex weather conditions and without using field measurements. Firstly, the time-space multiscale characteristics of the site meteorological parameters and the quantitative calculation method for the thermal radiation environment of the bridge under complex meteorological conditions are studied. A new approach is proposed to forecast the weather conditions of bridge site based on the shared meteorological data. Secondly, considering the effects of local characteristics of wind and insuring the thermal balance condition, a thermal-radiation coupling analysis method using the FE-based transit thermal analysis is developed, and thus the bridge temperature field under complex weather conditions can be finely calculated according to the surrounding meteorological parameters. Then, the history of one year’s three-dimensional temperature load and the corresponding temperature-induced static responses of a box girder bridge is calculated suing transit analysis method, subsequently, the temperature effects on a box girder bridge is evaluated for a specific and one year time . At last, the proposed method will be experimentally study suing construction materials, bridge components and scale box girder bridge models. Real box girder bridges are selected to carry on the investigation for the engineering validation and application of the proposed method. This project has important theoretical significance and great engineering application prospect for the analysis and evaluation of bridge temperature effect.