建筑结构学报2017，Vol.38Issue(7)：68-77,10.DOI:10.14006/j.jzjgxb.2017.07.009
单箱双室箱梁对称弯曲时的局部扭转效应
Analysis on local torsional behavior of twin-cell box girder under symmetrical bending
摘要
Abstract
By using force equilibrium and decomposition,the local torsional behavior of twin-cell box girders subjected to a symmetrical loading was presented.The formulas of forces and stresses of local torsion were deduced based on shear flow equilibrium on cross-section.Compared with model test and finite element numerical solutions of a simplesupported twin-cell box girder,the calculation formula of the local torsion was verified,and the stress law of local torsional behavior was analyzed.Results indicate that if the mid-web is subjected to vertical load or the two side-webs are subjected to equal vertical loads,accompanied by vertical flexural bending,the local torsion behavior is induced,including effect of torsion,distortion and lateral bending.The local torsion behavior can cause longitudinal stresses and transverse stresses on cross-section.The present theoretical solutions are in good agreement with the model test and numerical analysis results.Based on the shear flow equilibrium on cross-section,the load decomposition method is efficient for calculation of the local torsional force of twin-cell box girder.Local torsion effect is most prominent near the loading section.On the upper and lower plates of cross-section,the distributions of longitudinal stress and transverse stress show a broken line change where the inflection point is at the mid-web.The distributions and value of stresses are correlated with the position of load on the cross-section.For the example of box girder,the longitudinal stress caused by local torsion is 25 ％ of bending stress calculated by primary beam theory.关键词
单箱双室箱梁/竖向弯曲/局部扭转/模型试验/扭转效应Key words
twin-cell box girder/vertical bending/local torsion/model test/torsional behavior分类
建筑与水利引用本文复制引用
蔺鹏臻,阳放,雒敏,孙理想,杨子江..单箱双室箱梁对称弯曲时的局部扭转效应[J].建筑结构学报,2017,38(7):68-77,10.基金项目
国家自然科学基金项目(51368031),甘肃省基础研究创新群体项目(1506RJIA029),兰州交通大学优秀平台项目(201601). （51368031）
