冷弯薄壁斜卷边槽钢轴压构件的稳定性分析

为研究冷弯薄壁斜卷边槽钢轴压构件的稳定性能,选取了两种翼缘外廓尺寸(B=55 mm和B=80 mm)、七种卷边弯起角度(θ分别为30°、45°、60°、90°、120°、135°、150°)、三种板厚(t取为1.0、2.0和3.0 mm)、六种试件长度(L以0.5 m为间隔,由0.5 m起变化到3 m止)、简支和固支两种边界条件,对共计504个算例进行了轴心受压状态下的非线性有限元分析.研究了上述参数对斜卷边槽钢轴压构件稳定性能的影响.结果表明,θ对弹性畸变屈曲临界力影响显著,且对轴心受压简支构件而言,θ为钝角时能够有效地避免畸变屈曲的发生,若θ为30°构件的破坏模式不由畸变屈曲控制时,则其承载力最大;轴心受压固支柱比简支柱更容易出现畸变屈曲,且斜卷边槽钢大多不及相同条件下直角卷边槽钢的承载力.

Stability behavior analysis of channels with inclined simple edge stiffeners under axial compression

In order to investigate the stability behavior of channels with inclined simple edge stiffeners under axial compression,a total of 504 examples with two external flange dimensions(B = 55 mm and B = 80 mm),seven stiffener inclined angles(θ equals 30°,45°,60°,90°,120°,135° and 150°,respectively),three different thicknesses(t equals 1.0 mm,2.0 mm and 3.0 mm),six column lengths(L changes from 0.5 m to 3 m with a space of 0.5 m),pin-ended and fixed-ended boundary conditions were selected to be studied by nonlinear finite element analysis under concentric compression loading.The influence of the above parameters on stability behavior of channels with inclined simple edge stiffeners under axial compression was investigated.It is shown that θ has an obvious effect on distortional buckling critical load.For concentrically loaded pin-ended columns,the occurrence of distortional buckling can be avoided effectively if θ is an obtuse angle,and the column strength of channel with 30° slopping edge stiffeners will be the maximum if its failure mode is not controlled by distortional buckling.For concentrically loaded fixed-ended columns,distortional buckling happens easier than pin-ended columns,and most channels with inclined simple edge stiffeners have lower strength than channels with simple edge stiffeners perpendicular to the flanges under the same condition.