Failures and Prediction Methods of Lateral Buckling Strength of H-Shaped Beams Connected by Flush End Plates

Abstract

This paper presents boundary conditions for lateral buckling of the H-shaped beams connected to columns by flush end plates which fall into the lateral buckling following the out of plane plastic deformations of the flush end plates. The study is conducted by the following procedure: First, the behavior of the connection is researched by the no buckling experiment under the cyclic loading. As a result, it is found that the relationship between the out of plane plastic deformations of the endplates and the bending moment at the beam end can be predicted. Next, the FEM analyses of the rigid-frame structures consist of the slender beams having flush end plates connection and the structures consist of the beams having rigid connection are conducted to research the stress conditions in the tension flanges and the compression flanges of the beams during falling into lateral buckling. As a result, it is found that the rigid connection is restraining warping of the beam more tightly than the flush end plates connection, then the maximum bending moment strength against lateral buckling of the beams connected by rigid connections is higher than those of the beams connected by flush endplate. We recommend that the boundary conditions for the lateral buckling of the beams connected by flush end plates should be regarded to be different from those of the beams connected by the rigid connections.