单箱多室箱梁剪力滞效应参数研究

为研究单箱多室箱梁结构剪力滞效应及识别其影响参数,基于箱梁剪力滞理论分析模型,采用现行规范查图法和推荐公式法计算截面有效宽度的方法,系统分析了B/L(宽跨比)、翼缘悬臂长度等参数对箱梁剪力滞效应敏感度。结果表明:变截面单箱多室箱梁剪力滞效应主要受箱室宽度、悬臂长度、梁高及跨径控制;箱梁剪力滞效应以中跨梁段部分至支点截面次序增强;同时分析得到跨径与悬臂长度变化时,有效宽度折减系数的增减规律。

Parametric Analysis on Shear Lag Effects of Box-Girder Beam

In order to study the shear lag effects of the box-girder beam and its influencing parameters based on the analytical mode of shear lag theory, the present code and formula are adopted to calculate and analyze the sensitivity of B/L （ width/ span）, cantilever length and span to the shear lag effect. The results show that the shear lag effect of mid-span beam is under the control of width of box girder, length of cantilever, height, and span. The shear lag effect increases gradually from mid- span to pivot section; meanwhile, lhe ratio of effective width reduction is figured out when span and cantilever change.