摘要
为研究大挑臂钢箱结合梁截面的抗扭刚度,以黑瞎子岛乌苏大桥——(140+140)m的钢箱组合梁独塔单索面斜拉桥为对象,通过1∶4的缩尺节段模型试验和有限元计算,对单车道、双车道和3车道偏载工况下结构的扭转性能进行分析。结果表明:3车道偏载作用下,主梁的实测最大扭转角和最大剪应力为9.88×10-4 rad和14.71MPa,远小于桥面横坡2%和规范允许的125MPa,乌苏大桥钢箱组合梁截面具有足够的抗扭刚度,且富余量大;增加钢箱梁底板和腹板厚度可显著提高钢箱组合截面的抗扭刚度,而增加钢箱梁顶板厚度对截面抗扭刚度的提高有限。
To study the sectional torsional stiffness of the long cantilever steel box composite girder, the Wusu Bridge, a steel box composite girder cable-stayed bridge with a single pylon, single cable plane and with span arrangement （140＋140 m）, in Heixiazi Island was taken as the research object and by means of the 1 ： 4 scaled-down sectional model test and finite element calculation, the tosional behavior of the girder structure under the eccentric loading cases of a single lane, the double lanes and 3 lanes was analyzed. The results of the analysis indicate that under the eccentric loading case of the 3 lanes, the measured maximum torsional angle and maximum shear stress of the main girder are respectively 9.88× 10^-4 rad and 14.71 MPa, which are far less than the 2M transverse slope of the deck and the 125 MPa as allowed in the codes. The section of the composite girder of the Wusu Bridge has sufficient torsional stiffness and the margin of the stiffness is great. The increase of the thickness of the bottom plate and webs of the steel box girder can significantly increase the sectional torsional stiffness of the composite girder, however, for the increase of the torsional stiffness, the increase of the thickness of the top plate of the girder is limited.
出处
《桥梁建设》
EI
CSCD
北大核心
2014年第5期56-62,共7页
Bridge Construction
基金
黑龙江省交通运输厅科技计划项目(2011A013)~~
关键词
斜拉桥
结合梁
扭转刚度
节段模型
模型试验
有限元分析
扭转角
cable-stayed bridge
composite girder
torsional stiffness
sectional model
model test
finite element analysis
torsional angle
