Seismic Behavior of Knee-Braced Steel Moment Frames

Document Type : پژوهشی

Authors

• Amin Mohebkhah
• Alireza Bazvand

Malayer University

10.22067/civil.v31i1.47668

Abstract

Moment-resisting steel frames (MRSFs) have high ductility, however, suffer from low lateral stiffness and large lateral drifts. Recently, a new LFRS called knee-braced moment frame (KBMF) has been introduced in the literature in which the seismic behavior of an ordinary moment frame is improved using some knee elements as structural ductile fuses in the vicinity of beam-to-column moment connections. In this research, seismic behavior of some 3, 6 and 10 stories KBMFs with different span numbers are studied using nonlinear static and dynamic time-history analyses. The results show that the overstrength factor as well as behavior factor of KBMFs are considerably larger than the corresponding factors for MRSFs. Furthermore, it was observed that the column axial demands in KBMFs –except for the top stories- are smaller than those proposed in the Seismic Provisions for MRSFs.

Keywords

• Steel Frame
• Knee Bracing
• Time-history dynamic analysis
• nonlinear static analysis
• Seismic Parameters

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