中文摘要：

摘要：扁平钢箱梁在真实环境条件下的温度场及其温度作用效应是大跨钢箱梁桥全寿命性能设计的重要基础。基于润扬大桥斜拉桥结构健康监测系统的监测数据，采用假设检验和最小二乘估计等方法对扁平钢箱梁横截面实测温度和实测温差进行了统计分析，并采用数值逆变换抽样方法和温度样本调整方法建立了扁平钢箱梁温度场全寿命模拟方法。研究结果表明：扁平钢箱梁横截面实测温度服从2个正态分布的加权和，实测温差则服从2个Weibull分布的加权和；模拟生成的扁平钢箱梁横截面温度场的统计特性以及日变化和年变化规律与实测结果吻合较好，可用于润扬大桥斜拉桥钢箱粱的全寿命温度效应分析。

英文摘要：

Temperature field and temperature effects of flat steel box girder under realistic environmental conditions are important basis for the life-cycle performance design of long-span steel box girder bridges. Based on the field measurement data obtained from structural health monitoring system of Runyang cable-stayed bridge, the statistical characteristics of temperature and thermal differences in the flat steel box girder section are investigated by using the hypothesis testing and least-square estimation, and the life-cycle simulation method for the temperature field of flat steel box girder section is established using numerical inverse transform sampling method and temperature sample modification method. The results reveal that the measurement temperatures of flat steel box girder section may be described by the weighted sum of two normal distributions and the thermal difference among measuring points may be described by the weighted sum of two Weibull distributions. The statistical characteristics of simulated temperature field and its daily and annual variation laws agree well with the measured temperature field, and hence they can be applied to the life-cycle temperature effect analysis of steel box girder for Runyang cable-stayed bridge.