偏心受壓冷彎薄壁槽鋼的卷邊角度優化設計

吳夢景　黃栩浩　張旭　朱玨　趙銀海

摘要：

為了使得鋼結構的性能與用鋼量比達到最優，前人對槽型鋼的截面尺寸優化進行了較為充分的研究。但是，涉及卷邊角度的優化特別是偏心受壓工況下的優化分析卻很缺乏。以YaoTeng偏心受壓計算公式，結合遺傳算法，以冷彎卷邊槽鋼柱偏心受壓為例，將槽鋼卷邊角度與偏心距作為設計變量，尋找在不同偏心距受壓情況下，達到最大畸變屈曲臨界應力的卷邊角度。基于有限條分析程序，對兩端簡支與兩端固支情況下不同截面尺寸構件的畸變屈曲臨界應力進行了計算分析，最終得出不同偏心距受壓下統一的最優卷邊角度。為了方便工程設計人員設計時參考，建議卷邊角度統一取為100°。

關鍵詞：

偏心受壓；斜卷邊槽鋼；有限條；遺傳算法；最優卷邊角度

中圖分類號：TU391

文獻標志碼：A文章編號：16744764（2016）06009106

Abstract：

The optimization of the sectional dimensions is studied to make the ratio between performance and steel amount of steel sections become optimal. However， the optimization analysis of lip angle involving the eccentric compression is lack. A technique with the genetic algorithm and formulae for predicting the distortional critical stresses of coldformed lipped channels subjected to eccentric compression is developed to optimize the angles of lips of channels. The coldformed lipped channel columns under eccentric compressing have been taken as examples. The genetic algorithm regards the angle of lip and eccentric distance as design parameters. This method not only can decrease workload and aimless calculation but also can obtain accurate optimal angles. The distortional critical stresses of coldformed lipped channels with different dimensions under simply and clamped supports are obtained， based on the finite strip analyses. The optimal angles of coldformed channel steel members with different eccentric distances are presented. For designers convenience of design and application， the degree of 100 is suggested.

Keywords：

inclined lipped coldformed channel；eccentric compression；finite strip；optimal angle of lip

隨著生產技術的不斷更新發展，冷彎成型鋼構件朝著高強度、薄壁、截面形式復雜的趨勢發展，出現了幾種常見的屈曲模式，分別為：局部屈曲、畸變屈曲和整體屈曲[1]。由于可以用加勁及加支撐的方式來提高構件的局部屈曲和整體屈曲的臨界應力，畸變屈曲則很可能成為最終主導構件失效的屈曲模式。Lau 和 Hancock等[23]提出了簡化模型，推導出了受壓構件彈性畸變屈曲臨界應力。學者Li等[4]考慮翼緣板件彎曲的影響，在 Lau 和 Hancock 的畸變屈曲模型基礎上進行修正，并推導出了類似于 Lau 和 Hancock 公式的彈性畸變屈曲臨界應力計算公式。……