Seismic Performance of Chevron-Configured Special Concentrically Braced Frames with Yielding Beams

Authors

Hayato Asada, Kobe University
Andrew D. Sen, Marquette UniversityFollow
Tao Li, Sichuan University
Jeffrey W. Berman, University of Washington
Dawn E. Lehman, University of Washington
Charles W. Roeder, University of Washington

Document Type

Article

Publication Date

12-2020

Publisher

Wiley

Source Publication

Earthquake Engineering & Structural Dynamics

Source ISSN

1096-9845

Abstract

Current seismic design requirements for special concentrically braced frames (SCBFs) in chevron configurations require that the beams supporting the braces be designed to resist the demands resulting from the simultaneous yielding of the tension brace and degraded, post-buckling strength of the compression brace. Recent research, including large-scale experiments and detailed finite-element analyses, has demonstrated that limited beam yielding is not detrimental to chevron braced frame behavior and actually increases the story drift at which the braces fracture. These findings have resulted in new expressions for computing beam demands in chevron SCBFs that reduce the demand in the tension brace to be equal to the expected compressive capacity at buckling of the compression brace. In turn, the resultant force on the beam is reduced as is the required size of the beam. Further study was undertaken to investigate the seismic performance of buildings with SCBFs, including chevron SCBFs with and without yielding beams and X-braced frames. Prototype three- and nine-story braced frames were designed using all three framing systems, that is, chevron, chevron with yielding beams, and X SCBFs, resulting in six building frames. The nonlinear dynamic response was studied for ground motions simulating two different seismic hazard levels. The results were used to characterize the seismic performance in terms of the probability of salient damage states including brace fracture, beam vertical deformation, and collapse. The results demonstrate that the seismic performance of chevron SCBFs with limited beam yielding performs as well as or better than the conventionally designed chevron and X SCBFs.

Comments

Accepted version. Earthquake Engineering & Structural Dynamics, Vol. 49, No. 15 (December 2020): 1619-1639. DOI. © 2020 Wiley. Used with permission.

Recommended Citation

Asada, Hayato; Sen, Andrew D.; Li, Tao; Berman, Jeffrey W.; Lehman, Dawn E.; and Roeder, Charles W., "Seismic Performance of Chevron-Configured Special Concentrically Braced Frames with Yielding Beams" (2020). Civil and Environmental Engineering Faculty Research and Publications. 320.
https://epublications.marquette.edu/civengin_fac/320