Abstract: Based on reference[1],this paper derives the formula of the effective width of flange for estimating shear lag effect in box girder bridge.After studying the effective width of the simply supported and cantilever box girder of different ratios of width to span under point load or uniform load and consulting research reports and design codes concerned on box girder,the paper offers further proposals concerning the estimation of shear lag effect in box girder bridge to the current native highway bridge codes,which may be used as a reference for the design and modification of highway bridge codes.

Key words: box girder bridge, load, bending, stress, shear lag, (ratio of)effective width, ratio of width to span, design codes

摘要： 本文在用变分法分析箱梁桥剪滞效应研究的基础上,导出了箱梁桥翼板有效宽度的计算公式,通过对不同宽跨比的简支、悬臂箱梁在集中荷载和均布荷载作用下翼板有效宽度比的研究,并参考了国内外有关箱梁桥的研究报告和设计规范,对我国现行的公路桥涵设计规范有关箱梁桥剪滞效应的设计计算部分提出了进一步的建议条文,可供设计和修订规范时的参考。

关键词: 箱梁桥, 荷载(力), 弯曲, 应力, 剪力滞后(剪滞), 有效宽度(比), 宽跨比, 设计规范