Static And Danamic Analysis Of Space Steel Frames With Semi-Rigid Connections

The semi-rigid connection frame means that the rigidity of connection is not so rigid that it can transfer partially moment to column. Since Young performed the first experiment to estimate the rigidity of steel beam-to-column connections in University of Illinois in 1917, experimental testing has been continued and valuable connection databases have been founded. Initial rotation stiffness and ultimate moment resistance of connection have been gained by theoretic research baseing on experimental data. By means of this theory, moment-rotation curves of double web angle connections, top seat angle connections, top and seat angle with double web angle connections were gained, whose geometrical sizes were spesified inadvance.By the method of finite element, 12 space frame models were built up including double web angle connections, top seat angle connections, top and seat angle with double web angle connections and rigid connections, whose floor is 2-storey, 6-storey and 10-storey. Then lateral displacements were computed under wind loading, with the change of different storey and connection relative stiffness, the effect on maximum displacement and storey relative displacement were studied. The former three vibration modes were gained with model analysis, and period varieties of different connections were compared; time-history analysis were done by inputting ground motorial acceleration including El centro wave,Qianan wave and Taft wave. The effects of sereval facters including different storey, connection relative stiffness and different earthquake waves were studied on storey displacement and relative rotation angles. At last, column shear force was studied including rigid connection and semi-rigid connection.The results in this paper provide reference for further study on behavior of semi-rigid connection space frames and design of semi-rigid connection space frames.