NUMERICALLY INVESTIGATION OF THE BEHAVIOR OF LONG LINK-TO-COLUMN CONNECTIONS WITH REDUCED SECTION

Document Type : Research Paper

Authors

Abstract

Eccentrically braced frames (EBFs) combine the high elastic stiffness of concentrically braced frames with the ductility and stable energy dissipation of moment resisting frames. In these types of frames energy often dissipated through links that vary from short shear yielding to long flexural yielding link. Link-to-column connections in eccentrically braced frames must transmit large moments and shear forces to facilitate link rotation. Previous researches has shown that link-to-column connections in long links are prone to failure at low drift levels due to their susceptibility to fracture at the link flange-to-column connections and they aren’t applicable in sever seismic environments. To overcome this problem it is necessary to keep away stress and strain concentration from the ends of link connections. The use of link with reduced section can transmit plastic zone to reduced part and prevent connection failure. This paper investigates the application of RBS method in long links and studies the behavior of reduced long link to column connections. The analysis is conducted using the ABAQUS FEM software package. The analytical results show that this technique keeps away stress and strain concentration from the end of link beam near the face of column to some extent and improve the connection behavior.

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