腹板开孔冷弯薄壁槽钢构件有限元分析

FINITE ELEMENT ANALYSIS OF COLD-FORMED THIN-WALLED CHANNEL STEEL NON-PURE BENDING MEMBERS WITH WEB HOLES

为研究腹板开孔对冷弯薄壁槽钢非纯弯构件抗弯承载力及屈曲模式的影响,本文选取不同孔洞数目和不同孔洞尺寸的冷弯薄壁槽钢非纯弯构件进行有限元分析。结果表明:开孔较小的构件发生了畸变屈曲为主的失稳模式,开孔较大的构件发生了局部屈曲为主的失稳模式。梯度弯矩对畸变屈曲有较大影响,对局部屈曲有较小影响,导致开孔较小的构件承载力大于不开孔构件承载力,开孔较大构件承载力小于不开孔构件承载力。

In order to study the effect of web holes on buckling modes and flexural capacity of coldformed thin-walled channel steel non-pure bending members, finite element analyses were conducted on cold-formed thin-walled channel steel non-pure bending members with the different size and different number of web holes. The results show that structure in the condition of non-pure bending to low diameter-depth ratio produces instability when distortional buckling plays an important part, and under the circumstance of non-pure bending to high diameter-depth ratio produces instability when local buckling plays an important part. Gradient moment has a great influence on the distortional buckling, but has litde effect on the local buckling, whose results are low diameter-depth ratio bending strength is higher than no hole, high diameter-depth ratio bending strength is lower than no hole.