Performance of pristine and retrofitted hybrid steel/fibre reinforced polymer composite shear walls

Abstract

In this study new types of advanced hybrid shear wall systems using steel/fibre reinforced polymer (FRP) composites are being developed for deployment in the construction of buildings. The hybrid steel/FRP shear walls made from laminates of steel with either carbon FRP (CFRP) or glass FRP (GFRP) materials. In total six medium-scaled shear wall specimens were manufactured. In the first phase of the study three pristine specimens: steel shear wall (SSW-P), hybrid steel /CFRP shear wall (HSCSW-P) and hybrid steel/GFRP shear wall (HSGSW-P) were tested. In the second phase of the project, the specimens tested in phase one were retrofitted and retested; these specimens were identified as SSW-R, HSCSW-R and HSGSW-R. The structural repair and strengthening of specimens in the second phase was achieved by replacing the damaged infill plates with new infill plates of the same type, strengthening of the vertical steel frame elements with CFRP laminates and GFRP fabric. All shear wall specimens were tested under quasi-static cyclic loading following the ATC-24 protocol. The behaviour and failure modes of the pristine and retrofitted specimens were compared. The results show that the retrofitted specimens with the procedure developed have higher stiffness, higher ultimate loading capacity and similar energy dissipation capability relative to pristine specimens. For hybrid retrofitted specimens the ultimate load capacity increased more than 11% in comparison with pristine hybrid specimens.