大跨径钢桥沥青铺装疲劳应变三结构体系计算方法  

Computing Method of Fatigue Strain in Long-span Steel Bridge Asphalt Pavement Using Three-hierarchy Structure

作　　者：赵锋军[1] 李宇峙[1] 

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410004

出　　处：《公路交通科技》2011年第12期62-70,共9页Journal of Highway and Transportation Research and Development

基　　金：湖南省自然科学基金项目(10JJ3009);道路结构与材料交通重点实验室(长沙)开放基金项目(kfj080204)

摘　　要：为解决钢桥面沥青铺装疲劳设计应变没有解析公式的问题,进行了整桥平面弯曲应变简化计算模型、钢箱梁扭转横向弯拉应变计算简化模型、局部钢桥面沥青铺装叠层梁应变简化模型等3个结构体系的分析,采用弹性支承多跨连续梁模型与弹性地基梁模型,结合拉索当量支撑刚度、主梁抗弯刚度、钢箱梁截面抗扭刚度、桥面板加劲肋当量支撑刚度等作为计算参数,分析全桥最不利布载、最大偏心布载、最不利局部布载等3种布载方式,分析得到了3结构体系模型下钢板表面的弯拉应变计算方法。3结构体系计算结果表明,荷载作用下加劲肋造成的铺装表面横桥向弯拉应变对总应变的贡献率为80%以上,即使考虑设计车队荷载,主梁平面弯曲造成的铺装表面弯拉应变对总应变的贡献率不足15%,主梁扭转造成的铺装表面弯拉应变对总应变的贡献率超过15%。In order to derive the strain formulas of fatigue design for steel bridge asphalt pavement, the three- hierarchy structure, including simplified models of full-bridge plane bending strain, transverse flexural-tensile strain due to steel box beam torsion, and continuous laminated beam bending strain of partial bridge asphalt pavement, were analysed. Based on the elastic support multi-span continuous beam model, the elastic foundation beam model, and the main calculation parameters including equivalent support stiffness of bracing cable, bending stiffness of main beam, torsion stiffness of steel box beam section, and equivalent support stiffness of bridge deck stiffener, the worst load locations of full-bridge, eccentric load and partial load were analyzed, and the calculation method of flexural-tensile strain at steel deck surface using three-hierarchy structure model was obtained. The calculation results show that the contribution rate of transverse flexuraltensile strain at pavement surface under live loads being got by bridge deck stiffener model exceeded 80% , and that being got by plane bending model of main girder no more than 15% even if considering design fleet load, and that being got by main girder torsion model exceeded 15%.

关 键 词：桥梁工程 沥青铺装 计算方法 三结构体系 疲劳应变 

分 类 号：U433.33[交通运输工程—道路与铁道工程]