双工字钢-混组合连续弯梁桥有效宽度  

Effective Flange Width of Continuous Curved Steel-concrete Composite Bridges with Double Steel I-beams

作　　者：江林松 徐略勤[1,2] 熊光泽 陈叙先 JIANG Lin-song;XU Lue-qin;XIONG Guang-ze;CHEN Xu-xian(School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China;State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing 400074, China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074

出　　处：《科学技术与工程》2022年第2期795-803,共9页Science Technology and Engineering

基　　金：重庆市自然科学基金(cstc2019jcyj-msxmX0691);重庆市教委科学技术研究项目(KJQN201900737)。

摘　　要：由于中外现行设计规范缺乏针对钢-混组合连续弯梁桥桥面板有效宽度的规定,以小半径双工字钢-混组合连续弯梁桥为研究背景,首先对比分析了中外典型规范对钢-混组合连续直梁桥有效宽度的计算结果,然后基于数值模拟,分析研究了小半径双工字钢-混组合连续弯梁桥的剪力滞效应和有效宽度,探讨了曲率半径和布载方式的影响规律,最后考虑内、外侧主梁对应的桥面板剪力滞差异,提出了有效宽度的简化计算方法。研究结果表明:桥面板横断面正应力分布受弯扭耦合效应的影响较大,导致内、外侧主梁对应的桥面板正应力分布失去对称性,曲率半径越小,这种不对称性也越大,而车道外偏布置也会导致这种不对称性变大,工程设计计算中宜分别计算内、外侧主梁所对应的桥面板有效宽度;本文所提的简化计算方法能较好地包络有限元分析结果,且计算结果偏保守,可为同类桥梁的设计计算提供参考。Since the current domestic and foreign design codes lack provisions for the determination of effective flange width of the steel-concrete composite continuous curved bridge deck,a continuous curved bridge with small curvature radius and double I-beam steel-concrete composite deck was taken as the research background.Firstly,the calculation results of the effective flange widths were obtained and compared according to some typical domestic and foreign design standards for a straight version of the background bridge.Secondly,the shear lag effect and effective flange width of the background bridge were analyzed based on numerical simulations,and the effects of the curvature radius and loading pattern were discussed.Finally,taking into consideration of the differences in the shear lag between the inner and outer beams of the curved bridge deck,a simplified method for the calculation of effective flange width was proposed.The results show that the normal stress distribution of the bridge deck is greatly affected by the coupling effect of bending and torsion,leading to an unsymmetrical distribution of the normal stress between the inner and outer beams.With a smaller curvature radius,the condition of the unsymmetrical distribution of the normal stress becomes more significant.And the unsymmetrical distribution can also be found when the live loads are loading at the outer beam.It is reasonable to calculate the effective flange widths respectively for the inner and outer beams in the engineering design.The simplified calculation method proposed can provide a quite good envelope for the finite element analysis results,which is conservative for design,and therefore can provide a reference for the design and calculation of similar bridges.

关 键 词：连续弯梁桥 钢-混组合梁 有效宽度 曲率半径 布载方式 简化计算方法 

分 类 号：U448.216[建筑科学—桥梁与隧道工程]