Shear Buckling of Unstiffened Hybrid Beams

An investigation of the web buckling strength of hybrid beams was conducted with the specific objective of determining the maximum web slenderness ratio for unstiffened webs to prevent web buckling before general yielding in beams subjected to combined bending moment and shearing force. Theoretical equations were derived to predict the shear-buckling strength. Because the web of a hybrid beam yields before the flanges, the equations are written for any amount of web yielding. Six test results are presented for beams with A514 steel flanges and both carbon steel and high-strength low-alloy steel webs. The test variables included the web slenderness ratio, the depth of web yielding, and the web distortions. The experimental and theoretical results are in good agreement and shear buckling curves based on the theoretical equations are presented.