Abstract

RUIZ GARCIA, Jorge; BOJORQUEZ MORA, Edén; CORONA VILLAR, Edgar  and  REYES SALAZAR, Alfredo. Behavior of steel buildings with eccentrically braced frames subjected to seismic sequences. Ing. sísm [online]. 2019, n.100, pp.30-50. ISSN 0185-092X.

This paper presents the results of an analytical study focused on evaluating the seismic behavior of steel buildings having eccentric braced frames (EBFs) as structural system. For this purpose, two 4-story and 8-story EBFs were modeled using the computational platform OpenSees. Particularly, modelling strategy included the hysteretic behavior of the links in the eccentric braces taking into account a failure criterion as well as the panel zone in the beam-column joints. The case-study EBFs were subjected to a set of artificial mainshock-aftershock seismic sequences, which are representative of those recorded in soft soil sites of Mexico City. The results of this investigation reveal that the links can fail under strong aftershocks, which lead to an increment in the maximum interstory drifts with respect to those from the mainshock. In this situation, it was observed that the beams and columns near the link that failed can exhibit nonlinear behavior, which is opposite to its design philosophy. Finally, it was also noted that the EBFs tends to concentrate the maximum interstory drifts at the bottom stories since the links do not exhibit a uniform hysteretic behavior along height, which does not take fully advantaje of the energy dissipation capacity of the links.

Keywords : seismic sequences; eccentrically braced frames; steel frames; seismic response.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )