中文摘要：

以润扬大桥悬索桥和斜拉桥的扁平钢箱梁为研究对象，采用假设检验方法对扁平钢箱梁长期温度监测结果进行了温度分布特性分析，重点研究了扁平钢箱梁的横向温差和竖向温差分布特征，在此基础上采用极值分析方法计算了扁平钢箱梁的温差标准值，建立了钢箱梁温差计算模型，并针对悬索桥和斜拉桥的温度分布模式建立了6种最不利横向温差计算模型。研究结果表明：润扬大桥悬索桥和斜拉桥底板的横向温差可忽略；悬索桥和斜拉桥钢箱梁对称轴位置受相同的竖向温差作用；悬索桥和斜拉桥顶板的横向温度分布差异较大。

英文摘要：

With regards to the flat steel box girders of Runyang Suspension and Cable-stayed Bridge, temperature distribution characteristics were investigated using the long-term temperature monitoring results of flat steel box girders by means of hypothesis testing method. The distribution characteristics of transverse thermal differences and vertical thermal differences were analyzed in detail, based on which standard values of thermal differences for steel box girders were obtained using the extreme value analysis method and thermal difference calculation models were further proposed. The 6 types of horizontal temperature difference models for Runyang Suspension Bridge and Runyang Cable-stayed t were proposed, respectively with regards to various temperature distribution patterns. The results indicate that the horizontal temperature differences in bottom plates of Runyang Suspension and Cable stayed Bridges can be neglected; the vertical temperature differences in the symmetry axis of steel box girders are the same; the distribution characteristics of transverse thermal differences in top plates of Runyang Cable-stayed Bridge are quite different from those of Runyang Suspension Bridge.