日照扁平钢箱梁二维温度场的解析解  

Analytical solution of two⁃dimensional temperature field of flat steel box girder under sunlight

作　　者：李思阳 张玉平[1] 李传习[1] 李威 Li Siyang;Zhang Yuping;Li Chuanxi;Li Wei(Changsha University of Science&Technology,Changsha 410114,China;Guangdong Metallurgical and Design Institute Co.,Ltd.,Guangzhou 510080,China)

机构地区：[1]长沙理工大学,湖南长沙410114 [2]广东省冶金建筑设计研究院有限公司,广东广州510080

出　　处：《土木工程学报》2023年第11期64-77,共14页China Civil Engineering Journal

基　　金：国家重点发展研究计划发展计划(973)项目(2015CB057702);国家自然科学基金(52078059);湖南省教育厅创新平台资助项目(16K005)。

摘　　要：针对目前扁平钢箱梁日照作用下温度场的研究方法集中在数值模拟和长期实桥测试,尚未采用解析法研究的现状,根据热传导原理,建立带铺装层的扁平钢箱梁顶板与腹板的温度场模型,利用积分变换法求得二者温度场的解析解。以某独塔斜拉桥为例,重点对比分析顶板温度场实测值与解析解中太阳辐射强度分别采用实测法、Hottle法、幂指数法获得时的计算值,并根据太阳辐射强度采用实测法获得的解析解,进一步探究桥面防撞护栏与钢箱梁断面形式对顶板温度分布的影响。结果表明:在实测法获得的太阳辐射强度下,解析解计算结果与实测值最贴近,其计算值与实测值最大偏差不超过3℃,两者平均绝对误差最大不超过1.3℃;而在幂指数法与Hottle法中,太阳辐射强度采用幂指数法获得时,解析解计算准确度要更高;日照下,桥面防撞护栏遮挡引起的扁平钢箱梁顶板不均匀温度分布主要发生在该护栏附近的顶板位置,且引起的温度不均匀程度与太阳辐射强度呈正相关;PK断面钢箱梁与封闭断面钢箱梁顶板温度分布差异体现在是否开口位置,钢箱梁封闭箱室的保温效果导致箱内外环境温度不同是造成该差异的主要原因。In view of the fact that the current research methods for temperature field of flat steel box girder under solar radiation has been limited to numerical simulation and long⁃term field tests and the analytical method has been unavailable,the temperature field model of the top plate and web of flat steel box girder with paving layer is established based on the principle of heat conduction,and the analytical solution of temperature field of the top plate and the web are obtained by integral transformation method.With the single tower cable⁃stayed bridge taken as an example,the measured values of the top plate temperature field are compared to the calculated values of the analytical solution with the solar radiation intensity calculated by the measurement method,Hottle method and power exponent method respectively,and furthermore the analytical solution with solar radiation intensity calculated by the measurement method is employed to study the influences of bridge deck crash barrier and steel box girder section form on the temperature distribution of the top plate.The results show that with the solar radiation intensity calculated by the measurement method,the analytical solution agrees best with the measured values,because the maximum deviation between the calculated value and the measured value is no more than 3℃and the maximum absolute error between the two averages is no more than 1.3℃.When comparing the power exponential method to the Hottle method,the calculation accuracy of the analytical solution is higher if the solar radiation intensity is calculated by the power exponential method.Under sunlight,the uneven temperature distribution of the top plate of the flat steel box girder caused by the shelter of the bridge deck crash parapet mainly occurs at the top plate position near this parapet,and the degree of temperature unevenness caused is positively correlated with the intensity of solar radiation.The difference in temperature distribution between the top plate of PK section steel box girder and clo

关 键 词：桥梁工程 扁平钢箱梁 非稳态热传导 温度场 解析解 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]