Effect of high axial load on overstrength factor of intermediate links in EBFs

Mojarad, Masood; Daei, Maryam; Ghafari, Zahra

doi:10.48303/jsee.2024.2030587.1094

Effect of high axial load on overstrength factor of intermediate links in EBFs

Articles in Press

Document Type : Research Article

Authors

Masood Mojarad ¹

Maryam Daei ²

Zahra Ghafari ¹

¹ Department of civil engineering, Faculty of Civil Engineering and Transportation, University of Isfahan, Isfahan, Iran

² Department of Civil Engineering, Faculty of Civil Engineering and Transportation, University of Isfahan, Isfahan, Iran

10.48303/jsee.2024.2030587.1094

Abstract

Eccentric bracing frames (EBFs) are one of the most suitable seismic resistance systems due to their high strength, ductility and energy dissipation. In some EBF configurations, due to loading patterns or structural geometry, the link member can be subjected to a high axial load. The presence of high compressive axial loads increases the occurrence of buckling and thus reduces both its strength and ductility. Most of the studies conducted were on short links, and as mentioned in the commentary of AISC seismic regulations, the effect of axial load on the behavior of intermediate and long links has not been sufficiently investigated, which highlights the need for further study. In this research, numerical modeling is first validated with experimental results. After that, the overstrength factor of the intermediate links made of the European I-shaped sections subjected to axial loads is examined. The results indicate that the overstrength factor of intermediate links is lower than the prescribed value of 1.5 in the provisions.

Keywords

Eccentrically braced frame

Intermediate link

Overstrength factor

High axial load

Finite element modelling

Subjects