腹板加劲冷弯薄壁复杂卷边槽钢受压构件承载力试验研究

Experimental investigation on channel columns with complex edge stiffeners and stiffeners in web under compression loading

分别对复杂卷边槽钢、腹板中间进行形加劲复杂卷边槽钢、腹板中间进行V形加劲复杂卷边槽钢3种截面形式,共计30根简支受压试件进行了承载力试验,其中轴心受压试件18根,偏心受压试件12根。研究了腹板加肋复杂卷边槽钢受压构件的承载力、破坏模式及变形等性能。试验结果表明:腹板加劲有效地减小了板件宽厚比,大幅度提高了轴心受压构件及向腹板一侧偏心的受压构件的承载力,使畸变屈曲代替局部屈曲起主要控制作用。与相同用钢量下的复杂卷边槽钢构件相比,腹板中间进行形加劲可使轴心受压及向腹板一侧偏心的受压构件的承载力提高约60%~70%,腹板中间进行V形加劲可使轴心受压及向腹板一侧偏心的受压构件的承载力提高约40%~60%。有效形心偏移对偏压构件承载力的影响不可忽视。对试验进行了有限元模拟,计算结果与试验结果吻合良好。

A total of 30 simply supported compression members with three types of complicated sections including channels with complex edge stiffeners,channels with complex edge stiffeners and-type stiffeners in the web,channels with complex edge stiffeners and V-type stiffeners in the web were tested,where 18 members were subjected to axial compression and 12 subjected to eccentric compression. The ultimate load-carrying capacity,buckling mode and deformation behavior of these members were studied. The results show that stiffeners in web can reduce the element width-to-thickness ratio effectively and increase the ultimate load-carrying capacity of axially loaded members and eccentrically loaded members with eccentricity close to the web side obviously. This makes local buckling be replaced by distortional buckling to control the failure modes of members. Compared with channels with complex edge stiffeners under the same amount of steel,members with-type stiffeners can make the ultimate load-carrying capacity of axially loaded members and eccentrically loaded members with eccentricity close to the web side be increased about60% to 70%; members with V-type stiffeners can make the ultimate load-carrying capacity of axially loaded members and eccentrically loaded members with eccentricity close to the web side be increased about 40% to 60%. Influence of the effective centroid offset cannot be ignored for carrying capacity of members under eccentric compression loading.Tests were simulated by finite element analysis( FEA). The analysis results agree well with experimental data.