Abstract

'''In this paper, a suspended-zipper braced frame (SZBF) equipped with hybrid damper consisting of Added Damping and Stiffness (ADAS) metallic damper and shape memory alloy (SMA) wires is introduced. The proposed seismic-force-resisting system is designed by performance-based plastic design (PBPD) method, which in addition to a significant reduction in the residual displacement of the structure, can increase the collapse displacement amount by providing a suitable lateral strength and ductility compared to the conventional SZBF. A new method for designing the proposed hybrid damper is presented, in which two factors of highest hysteretic energy and the least consumption amount of SMA material is provided. The existing models in this paper are two high-rise 12- and 16-story SZBFs in two cases (a) with the conventional system and designed by force-based design method (b) with proposed hybrid damper and designed by the PBPD method. Seismic assessment of the proposed SZBF (PSZBF) by nonlinear static analysis is performed under two lateral load patterns of parabolic and uniform, in accordance with the FEMA-P695 in OpenSees software. Two parameters of the overstrength factor (Ω) and response modification coefficient (R) are evaluated from the analysis results. It is determined that the PSZBF does not lead to a significant change in the overstrength factor comparing to the conventional SZBF. Also, the PSZBF, in addition to reducing the consumption amount of used steel by about 7%, can increase the R parameter by about 50% compared to the conventional system.

Abstract

In this paper, a suspended-zipper braced frame (SZBF) equipped with hybrid damper consisting of Added Damping and Stiffness (ADAS) metallic damper and shape memory alloy (SMA) wires is introduced. The proposed seismic-force-resisting system is designed by performance-based plastic design (PBPD) method, which in addition to a significant reduction in the residual displacement of the structure, can increase the collapse displacement amount by providing a suitable lateral strength and ductility compared to the conventional SZBF. A new method for designing the proposed hybrid damper is presented, in which two factors of highest hysteretic energy and the least consumption amount of SMA material is provided. The existing models in this paper are two high-rise 12- and 16-story SZBFs in two cases (a) with the conventional system and designed by force-based design method (b) with proposed hybrid damper and designed by the PBPD method. Seismic assessment of the proposed SZBF (PSZBF) by nonlinear static analysis is performed under two lateral load patterns of parabolic and uniform, in accordance with the FEMA-P695 in OpenSees software. Two parameters of the overstrength factor (Ω) and response modification coefficient (R) are evaluated from the analysis results. It is determined that the PSZBF does not lead to a significant change in the overstrength factor comparing to the conventional SZBF. Also, the PSZBF, in addition to reducing the consumption amount of used steel by about 7%, can increase the R parameter by about 50% compared to the conventional system.

Abstract

Abstract