The effect of beam-column connection types to design of steel frames

Steel frames attract attention as construction systems used widely in terms of providing flexibility in architectural designs and earthquake-proofing among modern constructions built in recent years. In practice, two types of beam-column connections are taken into account in analyzing and designing steel frames. These connections are full rigid or full pinned. It is assumed that in full rigid connection there is no relative rotation between beam and column in the course of deformation of the frame; therefore moment is transferred from beam to column. It is accepted that in pinned connections, on the contrary of full rigid, there is no obstacles against rotation among units and therefore it is not possible to transfer moment from the beam to column. Experimental studies reveal that connections behave between these two extreme situations. As semi-rigid connections rotate in the course of deformation of the frame, they have the capacity to transfer moment from beam to column at the least. In this thesis, it is aimed to analyze the effect of rigid and semi-rigid joints on construction systems. In the first and second chapters, the analyzing and sizing principles of rigid connection frames and semi-rigid connection frames have been explained and main types of semi-rigid beam-column connections used in practice have been introduced. In the third chapter, the sizing principles of beam-column joint with end-plate according to LRFD-AISC specifications have been explained and numerical samples have been given. In the forth chapter, it is explained which regulations are necessary for the matrix-displacement method to be able to analyze beam-column joints as semi-rigid. In the fifth chapter, the ANSYS package has been explained with the finite element method. In the sixth chapter, three storey-two bay, four storey-four bay and six storey-two bay frames have been analyzed as rigid and semi-rigid and internal forces accumulated in a nodal point have been found. The beam-column joint has been designed under these forces according to the LRFD-AISC specification. The designs have been analyzed as rigid and semi-rigid and maximum normal force in a bolt, maximum shear force, bolt diameter and number, plate thickness and length have been compared. In the comparisons, it is understood that semi-rigid behavioral patterns yield more economical results.Key Words : steel frames, semi-rigid beam to column steel connections, finite element method, matrix-displacement method, beam to column connection with end plate