Analytical approach of buckling strength of yielding damped braced core (YDBC)

Document Type : Research

Authors

1 Professor, Dept. of Civil Eng., K. N.Toosi University, Tehran, Iran

2 Ph.d,.K.N.Toosi University, Tehran, Iran

3 Associate Professor, Dept. of Civil Eng., K. N. Toosi University of Technology, Tehran, Iran

Abstract

Abstract:
 
Previous research on bracing members show that the ductility of bracing members is compromised due to the buckling phenomena. Therefore, many researchers have tried to use special considerations to increase the fracture life of bracing members. Some of these recommendations such as increasing the slenderness ratio, using lower width to thickness ratio, increasing the out-of-plane stiffness of middle connection to increase the fracture life of the bracing members can be used in seismic upgrading of bracing members. In this paper, the buckling behavior of a special type of concentrically braced frame termed as yielding damped braced core is investigated for different percentage of central core. Empirical studies shows that separation of X-braces by central frame, influence the buckling behavior of the system and leads to occurrence of buckling in second mode shape in accordance with two half-sine wave. The theoretical studies shows that the buckling strength of the system increases in proportion to increase in central core rigidity. Using more flexible central core, results in increase the possibility of instability and vice versa. Hence, to enhance the buckling behavior of the system, it is strongly recommended to use a central core with proper rigidity
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Keywords


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