美标等肢单角钢轴心受力构件承载力研究  

Analysis of the Axially Loaded Bearing Capacity of Single Equal-Leg Angle Members Under American Design Code

作　　者：姜正德 周行 刘亮 程来 孙洪宇 JIANG Zhengde;ZHOU Hang;LIU Liang;CHENG Lai;SUN Hongyu(Quzhou Guangming Electric Power Design Institute Co.,Ltd.,Quzhou 324003,China)

机构地区：[1]衢州光明电力设计有限公司,浙江衢州324003

出　　处：《电力勘测设计》2022年第11期29-32,66,共5页Electric Power Survey & Design

摘　　要：单角钢轴心受力构件,由于其截面对称性不同于其他双轴对称构件,拉压承载力计算更为复杂。对美标AISC360-10规范中等肢单角钢轴心受力构件承载力计算进行研究,得出宽厚比大小是单角钢受压构件验算弯曲屈曲极限状态或弯扭屈曲极限状态的关键影响因素,而宽厚比的限值由屈服强度决定。弯曲屈曲极限状态下,有效长细比的控制尤为关键。等肢单角钢作为单轴对称构件,若宽厚比较大,受压破坏也可能是在部分截面屈服后发生屈曲,也就是弯扭屈曲失效模式,此时应考虑构件扭转长度,截面抗扭属性等方面因素的影响。剪力滞后系数是单角钢抗拉承载力计算中较为关键的参数,同时美标中认为受拉构件净截面断裂和毛截面屈服均属强度破坏,虽有一定的安全裕度,稳定破坏如位移超限等仍值得关注。The calculation of the axially loaded bearing capacity of single equal-leg angles is more complicated,because the cross sectional symmetry of it is different from other biaxial symmetric sections.Taking the single equalleg angles sections as an example,the axially loaded bearing capacity of it under American codes was studied,found that width-to-thickness ratio is the key factor to check the flexural buckling limit state or flexural-torsional buckling limit state when the angle is under compression,the limiting width-to-thickness is determined by the yield strength.The control of slenderness ratio is particularly important in the flexural buckling limit state.Single equal-leg angles sections may have flexural-torsional buckling limit state when the width-to-thickness ratio is relatively large,bucking may occur after partial sections yield under this limit state,so the factors such as torsional unbraced length and torsional properties of section should be taken into account.The shear lag factor is key factor to calculation the tensile strength of the single angle,also the limit states of tensile yielding in the cross section and tensile rupture in the net section are both belong to strength failure,although there is a certain safety margin,stability damage such as displacement transfinite is still worth watching for.

关 键 词：等肢单角钢截面 承载力 弯曲屈曲极限状态 弯扭屈曲极限状态 有效长细比 剪力滞后系数 

分 类 号：TM726[电气工程—电力系统及自动化]