Best Combination of Design Parameters for Buildings with Buckling-Restrained Braces
Buildings vulnerability due to seismic activity has been highly studied since the middle of last century. As a solution to the structural and non-structural damage caused by intense ground motions, several seismic energy dissipating devices, such as buckling-restrained braces (BRB), have been proposed. BRB have shown to be effective in concentrating a large portion of the energy transmitted to the structure by the seismic ground motion. A design approach for buildings with BRB elements, which is based on a seismic Displacement-Based formulation, has recently been proposed by the coauthors in this paper. It is a practical and easy design method which simplifies the work of structural engineers. The method is used here for the design of the structure-BRB damper system. The objective of the present study is to extend and apply a methodology to find the best combination of design parameters on multiple-degree-of-freedom (MDOF) structural frame – BRB systems, taking into account simultaneously: 1) initial costs and 2) an adequate engineering demand parameter. The design parameters considered here are: the stiffness ratio (α = Kframe/Ktotal), and the strength ratio (γ = Vdamper/Vtotal); where K represents structural stiffness and V structural strength; and the subscripts "frame", "damper" and "total" represent: the structure without dampers, the BRB dampers and the total frame-damper system, respectively. The selection of the best combination of design parameters α and γ is based on an initial costs analysis and on the structural dynamic response of the structural frame-damper system. The methodology is applied to a 12-story 5-bay steel building with BRB, which is located on the intermediate soil of Mexico City. It is found the best combination of design parameters α and γ for the building with BRB under study.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1130945Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 603
 R. Vargas, and M. Bruneau, “Analytical response and design of buildings with metallic structural fuses I,” Journal of Structural Engineering, vol. 135, nº 4, pp. 386-393, 2009.
 V. A. Segovia, and S. Ruiz, “Direct displacement-based design for buildings with hysteretic dampers, using best combinations of stiffness and strength ratios,” Journal of Earthquake Engineering, published on-line, 2016. http://dx.doi.org/10.1080/13632469.2016.1185054.
 AISC, Manual of Steel Construction, American Institute of Steel Construction, 14th Edition, Chicago Illinois, 2011.
 CoreBrace México, “Contravientos restringidos contra pandeo (CRP), Manual de información técnica y tablas de ayuda” (Buckling-restrained braces (BRB), Technical information manual and help tables), México D. F, 2016 (in Spanish).
 CSI, Analysis Reference Manual for ETABS 2015, Computers and Structures, Berkeley California, 2015.
 H. Nangullasmú, “Propuesta de criterios de diseño sísmico conforme a reglamento para marcos no dúctiles de concreto reforzado con disipadores histeréticos” (Proposal of seismic design criteria according to regulation for non-ductile reinforced concrete frames with hysteretic dissipation devices). Tesis de maestría, Universidad Autónoma Metropolitana, México D.F, 2011 (in Spanish).
 Normas técnicas complementarias para diseño por sismo. Gaceta official del Distrito Federal (Technical Regulation for Earthquake Resistant Design, Mexico City Building Code), 2004 (in Spanish).
 Chopra, Dynamics of Structures, Theory and Applications to Earthquake Engineering. Prentice Hall, Second Edition, 2001.