Earthquake Engineering and Structural Dynamics, cilt.52, sa.15, ss.5050-5071, 2023 (SCI-Expanded)
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.