截面构造对钢箱梁剪力滞效应及其稳定性的影响  

INFLUENCE OF DIFFERENT SECTION STRUCTURE ON THE STABILITY AND SHEAR LAG EFFECT OF STEEL BOX GIRDER

作　　者：王若林[1] 张慧敏[1] Wang Ruolin Zhang Huimin(School of Civil Engineering, Wuhan University, Wuhan 430072, Chin)

机构地区：[1]武汉大学土木建筑工程学院,武汉430072

出　　处：《钢结构》2017年第5期31-34,84,共5页Steel Construction

基　　金：国家自然科学基金资助项目(51278387)

摘　　要：由于混凝土箱梁桥在运营一段时间后,普遍出现腹板开裂和跨中挠度过大的病害。随着交通事业的迅猛发展,钢箱梁桥逐渐取代混凝土箱梁桥成为大跨度桥梁的理想桥型。钢箱梁也存在剪力滞效应,而且更加显著。通过改变钢箱梁截面构造,运用大型有限元软件ANSYS进行数值模拟,研究了梗腋和腹板厚度对钢箱梁剪力滞效应的影响。结果表明:钢箱梁设置梗腋和增加腹板厚度可提高其局部刚度,通过改变截面剪力流分布情况,引起截面正应力横向分布趋于均匀,改善剪力滞效应,提高其整体稳定性;梗腋横向尺寸和高度越大,越有助于改善剪力滞效应;腹板厚度的增加对改善剪力滞效应并不显著。The diseases of web cracks and excessive deflection at the mid-span commonly appear in concrete box girder bridge after a period of operation. With the rapid development of transportation,steel box girder is gradually becoming the ideal bridge of long-span bridges instead of concrete box girder. The shear lag effect also exist in steel box girder,and is more obvious. The paper researched on the effect of horizontal haunching and web thickness on the shear lag effect of thinwalled steel box girder,by changing the steel box girder cross section structure through the large finite software ANSYS.Obtained the conclusion that steel box girder with haunching area and thickness increase of web could improve its local rigidity,perfect the shear lag effect and global stability by changing the distribution of the shear flow on the cross section which caused the transverse distribution of section normal stress tended to uniform; the more the lateral dimension and height of horizontal haunching,the greater it could help to improve the shear lag effect; the increase of web thickness to improve the shear lag effect was not significant.

关 键 词：钢箱梁 剪力滞效应 有限元 稳定性 局部刚度 

分 类 号：U441[建筑科学—桥梁与隧道工程]