طراحی لرزه ای ساختمان دیوار برشی جفت شده مرتبط با دمپرهای هیسترتیک با استفاده از طراحی لرزه ای مبتنی بر انرژی Seismic Design of Coupled Shear Wall Building Linked by Hysteretic Dampers using Energy Based Seismic Design

1. Introduction Concrete structural walls are usually used as the main lateral force resisting system for both medium and highrise buildings. Due to their high stiffness and strength compared to the mainframe, they absorb considerable lateral forces when the structure is subjected to an earthquake. Architects mostly place these walls near the center of the building around the elevator, and often require that the walls have openings for either doors or windows. The result of having opening at every story level is a reduced lateral stiffness as the structural wall acts more similar to independent walls than a single system. The walls on either side of the opening are thus coupled together by beams. Such a system is called a coupled shear wall. The structural behavior of reinforced concrete coupled shear wall structures is greatly influenced by the behavior of their coupling beams. Flexure and shear are the two main modes of failure of the reinforced concrete coupling beams (Subedi, 1991). Coupled core wall offers an efficient lateral load resisting system. Performance of a coupled wall system depends primarily on ensuring that the coupling beam provides adequate stiffness and strength (Harries et al., 2006). Coupling beams with low-span depth ratios become shearcritical members which are expected to suffer brittle failure. Special reinforcement details are generally required to avoid the undesirable brittle failure of such coupling beams. As a result of damaging of coupling beams and losing their ability to resist shear forces, the structural deformation may increase significantly due to the reduced system stiffness and the walls will no longer be coupled. To prevent the development of a sliding shear failure and to increase the ductility of coupling beams and energy dissipation capacity, it has been shown (Priestley and Paulay, 1992; Paulay and Binney, 1974; Paulay and Santhakumar, 1976) that for the span to depth ratios of less than two, the combination of diagonal reinforcement with closely spaced transverse reinforcement is required in moderate to highly stressed beams. However, the ACI Building Code (ACI 318-08) proposed the reinforced detailing to ensure stable behavior of coupled beam, which is based on Paulay and Binney’s work (1974), is difficult to construct and often fails to maintain the integrity of the full concrete section through large displacement reversals. For simplifying the construction of coupling beam, the ACI building code has recently allowed the use of transverse reinforcement confining the entire coupling beam, as opposed to only the diagonal reinforcement cages. These details have been shown to be effective by Naish et al. (2009). Although these details are simpler, these are still hard to construct. Other coupling beam design alternatives have been proposed and investigated (Harries, Gong and Shahrooz, 2000), including various reinforced concrete, steel, and hybrid steel-concrete coupling beam and posttensioned hybrid coupled wall designs (Kurama and Shen, 2004). There are various methods that have been suggested in order to solve the problem regarding complicated reinforcement details of coupling beam and verified analytically and experimentally (Chung et al., 2009; Kim et al., 2012; Oh et al., 2012) and confining the concrete at the base (I.D.Lefas et al., 1990; Vecchio, 1992) and using the high strength concrete (Parra-Montesinos et al., 2005; Lequesne Rémy et al., 2011).