INTERACTION EFFECT BETWEEN A BEAM OR COLUMN AND THE CORE AREA OF AN ECCENTRIC STEEL JOINT

Eccentric beam-column steel joints can be used to enhance the flexibility of building layouts. However, the eccentricity can cause stress concentrations, and has a negative influence on the mechanical properties of the joints. This paper presents a study of the mechanical performance of steel eccentric beam-column joints using FE models. The three dimension torsion effect is proved to exist in eccentric steel joints, while distortion and warping is observed to exist in sections of the beams and columns. A series of simplified assumptions were made based on the mechanical performance analysis, and a model focusing on the interaction effect between the beam or column and the core area of the eccentric joint is proposed. The simplified assumptions of the model were compared with the mechanical performance obtained from the FE models, and a revised coefficient is adopted for the distortion angle in order to coincide with the character of the distortion angle in the FE models. The proposed model in this paper is accurate when predicting the ratio of the distortion warping stress and the bending stress.