Seismic Performance of Linked-Column Frame; Multi-Parameter Study

Abstract In the current research, the effect of length and number of link beams on the structural response of Linked-Column Frames (LCFs) with different heights has been studied and compared with Special Moment-Resisting Frames (SMRFs). To this aim, 34 LCFs of 3-, 6-, and 9-story with two or three links in story level were designed in ETABS and simulated in OpenSees. The beam length ranged between 1-3.5 m altering plastic behavior from shear to flexure. Nonlinear dynamic analysis was carried out using 20 numbers of far-field and near-field records from FEMA-P695 scaled to DBE and MCE seismic hazard levels. Results illustrated that increasing the length and number of links generally reduced seismic demands. However, conflicting trends were observed in shear-flexure cases producing the greatest drift ratio and lowest base shear at the same time. Also, near-field records maintained almost similar demands compared to the far-field set except for the significantly different base shear responses. The results of 3-story LCFs were more promising in terms of a larger reduction in demands compared to the same height SMRF; utilizing LCF reduced SMRF drift ratio up to 72% in 3-story, and almost 26% in 6- and 9-story structures. The desirability coefficient determined the most suitable configuration for link beams, suggesting three numbers of 1.5 m shear links for 3-story LCF, and 3 m intermediate links with 3 and 2 numbers for 6- and 9-story structures, respectively. In conclusion, LCF system is not economical for taller buildings due to the relative weight increase.