Development of a Steel Brace with Intentional Eccentricity and Experimental Validation
Publication: Journal of Structural Engineering
Volume 143, Issue 8
Abstract
Conventional buckling braces are the most commonly used steel bracing systems but are characterized by intense local midlength buckling that leads to unstable energy dissipation and finally fracture. Moreover, they are unable to dissipate energy in the event of low-level earthquakes and provide limited post-yielding stiffness. The present paper proposes a prototype design of conventional buckling braces with improved seismic performance by introducing eccentricity along the brace length. Steel braces with intentional eccentricity (BIE) are deformed by small story drift. The inherent moment caused by eccentricity affects their response, and the braces display trilinear behavior under tension and transition smoothly to post-buckling behavior under compression. Owing to the moment contribution, stresses and strains are uniformly distributed along the brace length, delaying local buckling concentration, and, thus, the member’s life is appreciably extended. The present experimental work on BIEs reveals that the braces offer a reduced stiffness up to 56% on the initial stiffness maintaining the same strength with the corresponding conventional brace, provide large tensile post-yielding stiffness of 14–18% of the initial stiffness, stably dissipate energy during cyclic loading, and delay local buckling and fracture until large story drift levels (up to 2 and 4%, respectively).
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References
AIJ (Architectural Institute of Japan). (2012). Recommendations for design of connections in steel structures, 3rd Ed., AIJ, Tokyo (in Japanese).
AISC. (2010a). Steel construction manual, 14th Ed., Chicago.
AISC. (2010b). “Seismic provisions for structural steel buildings.” ANSI/AISC Standard 341-10, Chicago.
AISC. (2010c). “Specification for structural steel buildings.” ANSI/AISC Standard 360-10, Chicago.
Baiguera, M., Vasdravellis, G., and Karavasilis, T. L. (2016). “Dual seismic-resistant steel frame with high post-yield stiffness energy-dissipative braces for residual drift reduction.” J. Constr. Steel Res., 122, 198–212.
Chen, W.-F., and Atsuta, T. (2008). Theory of beam-columns. Volume 1: In-plane behavior and design. McGraw-Hill, New York.
Chopra, A. K. (2012). Dynamics of structures: Theory and applications to earthquake engineering, 4th Ed., Prentice Hall, Englewood Cliffs, NJ.
Christopoulos, C., and Pampanin, S. (2004). “Towards performance-based seismic design of MDOF structures with explicit consideration of residual deformations.” J. Earthquake Tech., 41(1), 53–73.
Fell, B. V., Kanvinde, A. M., Deirlein, G. G., and Myers, A. T. (2009). “Experimental investigation of inelastic cyclic buckling and fracture of steel brace.” J. Struct. Eng., 19–32.
FEMA. (2012). “2009 NEHRP recommended seismic provisions: Design example.”, Washington, DC.
Fu, Y., and Kasai, K. (1998). “Comparative study of frames using viscoelastic and viscous dampers.” J. Struct. Eng., 513–522.
García, R. J., and Miranda, E. (2003). “Inelastic displacement ratios for evaluation of existing structures.” Earthquake Eng. Struct. Dyn., 32(8), 1237–1258.
Hsiao, P. C., Lehman, D. E., and Roeder, C. W. (2012). “Improved analytical model for special concentrically braced frames.” J. Constr. Steel Res., 73, 80–94.
Iemura, H., Takahashi, Y., and Sogabe, N. (2006). “Two-level seismic design method using post-yield stiffness and its application to unbonded bar reinforced concrete piers.” Struct. Eng./Earthquake Eng., 23(1), 109–116.
Lai, J.-W., and Mahin, S. A. (2014). “Steel concentrically braced frames using tubular structural sections as bracing members: Design, full-scale testing and numerical simulation.” Int. J. Steel Struct., 14(1), 43–58.
Lehman, D. W., Roeder, C. W., Herman, D., Johnson, S., and Kotulka, B. (2008). “Improved seismic performance of gusset plate connections.” J. Struct. Eng., 890–901.
Lumpkin, E. J., et al. (2012). “Investigation of the seismic response of three-story special concentrically braced frames.” J. Constr. Steel Res., 77, 131–144.
Merczel, B. D., Aribert, J.-M., Somja, H., Hjiaj, M., and Lógó, J. (2015). “On the weak store behavior of concentrically braced frames.” Proc., 8th International Conf. on Behavior of Steel Structures in Seismic Areas, China Architectures & Building Press, Beijing.
Montgomery, M., and Christopoulos, C. (2015). “Experimental validation of viscoelastic coupling dampers for enhanced dynamic performance of high-rise buildings.” J. Struct. Eng., .
Nakashima, M., Saburi, K., and Tsuji, B. (1996). “Energy input and dissipation behavior of structures with hysteretic dampers.” Earthquake Eng. Struct. Dyn., 25(5), 483–496.
Okazaki, T., Lignos, D. G., Hikino, T., and Kajiwara, K. (2013). “Dynamic response of a chevron concentrically brace frame.” J. Struct. Eng., 515–525.
Takeuchi, T., and Matsui, R. (2011). “Cumulative cyclic deformation capacity of circular tubular braces under local buckling.” J. Struct. Eng., 1311–1318.
Tremblay, R. (2002). “Inelastic seismic response of steel bracing members.” J. Constr. Steel Res., 58(5–8), 665–701.
Uang, C. M., Nakashima, M., and Tsai, K. C. (2004). “Research and application of buckling-restrained braced frames.” Int. J. Steel Struct., 4(4), 301–313.
Watanabe, A., Hitomi, Y., Saeki, E., Wada, A., and Fujimoto, M. (1988). “Properties of brace encased in buckling-restraining concrete and steel tube.” Proc., 9th World Conf. on Earthquake Engineering, Japan Association for Earthquake Disaster Prevention, Tokyo, 719–724.
Ye, L. P., et al. (2008). “Study on the influence of post-yielding stiffness to the seismic response of building structures.” Proc., 14th World Conf. on Earthquake Engineering, China Earthquake Administration Ministry of Construction, Beijing.
Yoo, J.-H., Lehman, D. E., and Roeder, C. W. (2008). “Influence of connection design parameters on the seismic performance of braced frames.” J. Constr. Steel Res., 64(6), 607–623.
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©2017 American Society of Civil Engineers.
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Received: Mar 1, 2016
Accepted: Feb 3, 2017
Published online: Mar 27, 2017
Published in print: Aug 1, 2017
Discussion open until: Aug 27, 2017
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