中文摘要：

为选取合适的日照作用下混凝土箱梁温度场边界条件计算公式,对既有太阳直接辐射、散射辐射、地面反射、对流换热、辐射换热、大气综合温度的计算公式和取值进行了综合对比分析,以齐甘嫩江大桥温度场实测结果为基础,结合温度场分析有限元程序,研究了不同太阳直接辐射强度、散射辐射强度、地面反射辐射强度公式对箱梁顶板、腹板和底板温度场的影响,探讨了便于工程应用的辐射换热系数的合理取值范围,桥梁与环境温差和风速对对流换热系数的影响,以及箱梁不同部位的外界大气温度取值对箱梁内部温度场的影响规律。结果表明：太阳直接辐射强度对箱梁顶板温度分布影响较大,散射辐射强度对箱梁顶板和腹板温度分布影响较大,选择合适的太阳直接辐射和散射辐射强度计算公式能有效提高混凝土箱梁的温度场计算精度;地面反射及辐射换热中的斜面天空辐射效应分别对箱梁底板和顶板温度分布影响较大,在设计计算中不应忽视;综合考虑温差和风速计算得到的对流换热系数能较为准确地计算混凝土箱梁结构的温度场;辐射换热系数取值受外界条件影响较小,可在一定范围内取值;计算箱梁不同部位的综合大气温度时,应考虑相应部位的外界大气温度。

英文摘要：

In order to choose appropriate formulas to calculate the temperature field boundary conditions for concrete box-girder bridges under solar radiation,the existing formulas and values of direct solar radiation,diffusion radiation,ground reflection,convection coefficient,radiation coefficient, and comprehensive atmospheric temperature were compared and analyzed synthetically.Based on the temperature field experimental results of Qigan Nen River Bridge and the finite element program of temperature field analysis,the influences of different formulas of solar direct radiation intensity,diffusion radiation intensity and ground reflection radiation intensity on the roof,web and floor of box-girder were investigated.The reasonable range of radiation heat transfer coefficient which was suitable for engineering application was discussed.The heat convection coefficient which was affected by temperature difference between bridges and environment and wind speed was investigated.In addition,the influence laws of ambient atmospheric temperature values of different parts of box-girder on temperature field inside box-girder were researched.The results show that the solar direct radiation intensity has a great influence on the temperature distribution on the roof of box-girder,and the temperature distributions on the roof and web of box-girder are greatly influenced by the diffusion radiation intensity.The suitably selected formulas of direct radiation and diffusion radiation intensity can improve the calculation accuracy of temperature field on concrete box-girder.The effects of slant sky radiation in ground reflection and radiation heat transfer on the temperature distributions on the roof and floor of box-girder respectively are great,which cannot be ignored in design and calculation.The temperature field on concrete box-girder structure can be calculated accurately by comprehensively considering the convection coefficient which is calculated by temperature difference and wind speed.The value of radiation heat transfer coefficie