Performance-based Seismic Design Of Steel Frames With Semi-rigid Connections

The steel framework is one of the most commonly used structural systems in modern constructions . The conventional analysis and design of steel frames treat the connecting joints as either perfectly rigid or pinned . However ,most connections used in current practice are semi-rigid types whose behavior lies between perfectly rigid and pinned .The aim of the paper is to provide a practical method of the design of semi-rigid connections . The method can consider the actually performance of the semi-rigid connections in the static design and dynamic analysis .To achieve the aiming , actually modeling of their moment-rotation relationship is necessary if the effects of connections are to be considered in the structural design and analysis . In the seismic analysis , the moment-rotation hysteresis behavior of semi-rigid connections is a key problem. This paper represents an approach toward formulationg analytical models to predict the moment-rotation behavior of top and seat angle with double web angle connections , which are commonly used in the design of steel frame structures . The model of moment-rotation for top and seat angle with or without double angle connections is reasonable when it is compared with the experimental results .Through the research work of the thesis ,we can conclude the steel frames with semi-rigid connections are very efficient in resisting forces generated from ground motion and the use of semi-rigid connections in steel structures can result in very economical designs when properly designed .