对数律和指数律风剖面的差异分析及其对桥梁抗风性能评价的影响  

Comparative Analysis on Difference of Logarithmic Law and Power Law Wind Speed Profile and Its Influence on Evaluation of Bridge Wind-Resistant Performance

作　　者：毛汇 杨詠昕[1,2] 朱进波 郑史雄[3] 葛耀君[1,2] MAO Hui;YANG Yongxin;ZHU Jinbo;ZHENG Shixiong;GE Yaojun(Department of Bridge Engineering,Tongji University,Shanghai 200092,China;State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]同济大学桥梁工程系,上海200092 [2]同济大学土木工程防灾减灾全国重点实验室,上海200092 [3]西南交通大学土木工程学院,成都610031

出　　处：《结构工程师》2024年第1期22-28,共7页Structural Engineers

基　　金：国家自然科学基金项目(52178503)。

摘　　要：现有的公路桥梁抗风设计采用指数律风速剖面来计算各个基准高度的平均风速,然而气象学实践和一些国家规范中早已采用对数律风速剖面,两种风速剖面在不同高度处的平均风速差异及其对桥梁抗风的影响应当值得关注。对比了不同地表粗糙类型下对数律模型和指数律模型在不同高度处的风速差异,并采用ANSYS有限元软件计算了实桥在风荷载下的位移和桥塔弯矩差异。结果表明,在地表粗糙度较大和离地高度较大时,对数律和指数律模型的风速差异较为明显,风荷载的差异对桥梁内力和位移造成的影响不可忽略。有必要进一步研究这两种风速剖面模型在高空处的准确性,以更好地指导桥梁的抗风设计。The power law wind speed profile is currently used to calculate the mean wind speed at various reference heights for the wind-resistant design of highway bridges.However,the logarithmic law has already been used in meteorological practice and some country’s codes.In this instance,the disparity in mean wind speed for these two wind speed profiles at various heights and its impact on the assessment of bridge windresistant performance should be of concern.This study compared the wind speed differences at various heights and various surface roughness types and computed the variations in displacement and bending moment of a bridge under wind load using ANSYS finite element software.The results show that as height and surface roughness increase,the wind speed difference between the two winds becomes more obvious,and it is impossible to ignore the effects of differences on the internal force and displacement of the bridge.To get better guide the wind resistance design,more research is required to assess the two wind speed profile models'accuracy at high altitude.

关 键 词：风剖面 平均风速 斜拉桥 风荷载 静风响应 

分 类 号：U441.2[建筑科学—桥梁与隧道工程] U448.27[交通运输工程—道路与铁道工程]