考虑剪切滑移的波纹钢腹板预应力箱梁抗弯承载力计算  

Calculation of Flexural Capacity for Prestressed Box Girder with Corrugated Steel Webs Considering Shear Slip

作　　者：任红伟[1] 刘保东[2] 李鹏飞[2] 

机构地区：[1]交通运输部公路科学研究院,北京100088 [2]北京交通大学土木建筑工程学院,北京100044

出　　处：《公路交通科技》2012年第3期86-91,共6页Journal of Highway and Transportation Research and Development

基　　金：国家自然科学基金项目(50878099);交通运输部西部交通建设科技项目(200831822367)

摘　　要：为了计算体外预应力波纹钢腹板组合箱梁桥的极限抗弯承载力,针对其构造特点,考虑波纹钢腹板与顶底板混凝土剪力连接键剪切滑移的影响,推导了波纹钢腹板预应力箱梁极限抗弯承载力计算公式。滑移应变增大了顶底板的应变和截面曲率,可以通过附加弯矩考虑界面滑移对极限抗弯承载力的影响;在分析体外预应力钢筋与梁体变形协调关系的基础上,得到了体外预应力筋的应力增量,推导并总结了应用塑性铰法计算波纹钢腹板体外预应力组合箱梁极限抗弯承载力的步骤,并通过模型试验对该方法进行了验证。试验与理论分析的对比结果表明:考虑剪力连接键剪切滑移会减小极限抗弯承载力;推导得出的公式的计算结果优于同类现有方法,与实测数值接近,可用于同类箱梁设计的参考。In order to calculate the ultimate flexural capacity for externally prestressed box girder with corrugated steel webs,in view of its structural characteristics,considered the shear slip of shear key between the corrugated steel webs and the roof and floor concrete,the formulas of the ultimate flexural capacity of the externally prestressed box girder with corrugated steel webs were derived.As the slip strains increased the strain of the roof and floor and the sectional curvature,the influence of the interfacial slip on the ultimate flexural capacity were taken into account by the additional moment.Based on the analysis of the compatibility relation between externally prestressed tendons and the beam deformation,the stress increment of the external prestressing tendons was derived,the calculating steps of the ultimate flexural capacity of the externally prestressed box girder with corrugated steel webs by the plastic hinge method were derived and summarized,and the method was verified by model tests.The comparison of the experimental and theoretical results indicate that（1） the ultimate flexural capacity will be reduced when considering shear slip of the shear key;（2） the results obtained using the derived formulas are better than those from existing methods,which are close to the measured values and can give a reference to the calculation of the same type of girders.

关 键 词：桥梁工程 波纹钢腹板箱梁 抗弯承载力 剪切滑移 体外预应力 

分 类 号：U448.216[建筑科学—桥梁与隧道工程]