Finite element analysis of space steel frame with semi-rigid connection

In the current practice of analysis and design of steel-framed building structures, the actual behaviour of beam-column connections is generally simplified to the two idealized extremes of either fully rigid behaviour or ideally pinned behaviour. However, most connections used in current practice actually exhibit semi-rigid deformation behaviour that can contribute substantially to overall displacements of the structure and to the distribution of member internal force. In the traditional design and analysis on steel frames, the beam-column connection whose behavior affects steel frames overall performance, was assumed as rigid or pinned, which couldn't reflect the actual fact. Nonlinear finite element analysis for typical beam-column connections steel frame was performed in this paper. It were analyzed that the conditions of stress development, the distributing of stress and the appearing orders of plastic hinges of space steel frame with top-seat and web angles connections and with extended-end-plate connections under cyclic loading. At last, some conclusions about effect of joint stiffness on the side sways of the vertices and on the internal force of the vertices in space steel frame are obtained in this paper.