Moment-rotation curves for semi-rigid top and seat angle connections

Abstract

Beam-to-column connections are vital components whose behavior affects the overall structural response of moment resisting steel frames. During the frame analysis and design step, connections are assumed as pinned or rigid type, but it has been observed that in actual practice most of the connections fall under the semi-rigid category. Though the analysis procedures for semi-rigid connections are more tedious, the final design proves to be more economical. The top and seat angle connection which has been traditionally considered as a pinned connection for simplifying frame analysis, is found to exhibit semi-rigid behaviour. In the present paper, all-bolted top and seat angle connections are investigated in detail by finite element analysis. The effect of geometric parameters of the connection on the monotonic moment-rotation relationship is ascertained by parametric studies. Equations to generate the M-θ curve for connection using the three parameter power model is also developed for the bolted top and seat angle connection.