介绍轻型门式框架I形截面钢构件腹板的设计原则和方法.首先从防止受压翼缘压入腹板来分析腹板高厚比的最大限值,其次分别论述腹板受剪屈曲后的极限剪力计算、受弯或压弯屈曲后有效宽度的确定,以及正应力和剪应力联合作用下屈曲后相关关系的计算. This paper introduces the design principles and methods for the webs of lightweight portal frames with I-section steel members. First, the maximum limit value of the ratio of web thickness to thickness is analyzed by preventing the pressure flanges from being pressed into webs. Then, the webs are discussed after they have been subjected to shear buckling. The calculation of the ultimate shear force, the determination of the effective width after bending or bending buckling, and the calculation of post-buckling correlations under the combined action of normal stress and shear stress.