USE OF GLASS FIBER POLYMERS (GFRPS) FOR STRENGTHENING OF SEMI-SUPPORTED STEEL SHEAR WALL

During the recent past decade, semi-supported steel shearwalls (SSSW) have been introduced as an alternative tothe traditional type of steel plate shear walls (SPSW).In this system, the shear wall does not connect directlyto the main columns of the building frame, instead, itis connected to a pair of secondary columns that do notcarry gravity loads. However, a SSSW system, comparedto the corresponding SPSW system in which theinll plate is connected to the main frame columns, has alower span width (or lower inll plate width) and, thus,lower strength, stiness,energy dissipation capability.To oset these eects, one eective,practical approachis the use of ber-reinforced-polymers (GFRPs)for strengthening the steel inll plate. GFRP laminatescan be easily attached to one or both sides of the inllplates by the use of adhesive. In this paper, the behaviorof semi-supported steel shear walls reinforced byglass-ber-reinforced-polymers (GFRPs) is studied usingthe nite-element method,compared with thecorresponding systems without the reinforcement. Anumber of semi-supported steel shear walls with differentplate aspect ratios, plate thicknesses, secondarycolumn proles,with,without opening of varioussizes is considered for this research. Both pushoverand cyclic analyses are performed. The adequacy ofthe nite-element modeling approach for representingthe pushover,cyclic responses of SPSWs is veriedthrough comparisons with experimental results. Resultsshow that the use of GFRP laminates, especially for thesystem with thinner inll plate thickness, can signi-cantly increase the system strength, initial stiness, andenergy dissipation, while it partially decreases the systemductility. In turn, the improvement of the systemstrength,energy dissipation capability is mainly dueto the improvement of the SSSW inll plate behavior. Infact, the use of GFRP laminates does not aect much thehysteresis,pushover behavior of the SSSW frames.