Frictional mid‐spliced shear links for eccentrically braced frames

Abstract

According to the AISC Seismic Provisions for Structural Steel Buildings (AISC341‐16) and EC8, the inelastic rotation demand at the design story drift is limited to 0.08 rad for I‐shape shear links in eccentrically braced frames (EBFs). Numerical studies on EBF archetypes show that the single‐sided inelastic rotation demands can be much higher than the limiting value. In addition, these links can fail due to low‐cycle fatigue (LCF) which depends on the loading history. A mid‐spliced end‐plated detachable replaceable link has recently been developed to promote easy replacement of end‐plated links. In this paper, a frictional mid‐spliced shear link is developed to increase the inelastic link rotation capacity and LCF life of shear links. The proposed link utilizes a splice connection at the mid‐length, where frictional faying surfaces are introduced to dissipate energy. Slip at the mid‐splice connection causes a relative vertical displacement between the link ends which eventually reduces the rotation demands on the I‐shape members. Experimental and numerical studies were conducted to study the proposed link concept. Three conventional and eight frictional mid‐spliced links were tested using a nearly full‐scale test setup. The results showed that the proposed links have a pinched link shear versus link rotation response. The links were able to sustain a link rotation demand of 0.23 rad together with a significant increase in their LCF life. Numerical studies were conducted to investigate the link rotation, interstory drift, and residual interstory drift of EBF archetypes equipped with the proposed frictional link.

Seismic Performance and Calculation Method of Precast Reduced Beam Section Connection

“…Zhang et al [21] proposed a high-strength steel framed-tube structure with replaceable link beams and performed low-cycle reciprocating loading tests on its substructures, showing that the damage under the action of an earthquake was concentrated in the energy-dissipation beam section, and the remaining main components were in the elastic phase. In recent years, Özkılıç et al [22][23][24][25][26][27][28][29][30] proposed various innovative connections to address the challenging issue of post-earthquake structural repair. An extensive series of experiments, FE analysis, and theoretical investigations were developed to study the load-bearing mechanisms of these novel connections.…”