Experimental study of steel plate shear walls with infill plates strengthened by GFRP laminates

In this paper, the nonlinear behavior of the composite steel plate shear walls, in which steel infill plates was strengthened by the fiber reinforced polymers (FRP), is experimentally investigated. Tests are designed to evaluate the effect of Glass-FRP layers, the number of GFRP layers and the orientation of GFRP layers on the stiffness, shear strength, cumulative dissipated energy and other major seismic parameters in the composite steel plate shear walls. Experimental models are scaled as one-story steel shear panel models with hinge type connections as boundaries at four corners. In the first test, unstiffened steel infill plate is used for the testing as a reference test. However, in the next four tests, strengthened steel infill plates were used with different numbers and orientation of GFRP layers. Each test was performed under fully reversed cyclic quasi-static loading in the elastic and inelastic response zones of the specimens, in compliance with the ATC-24 (1992) test protocol. The experimental results indicated that by strengthening the infill steel plates yield by laminates strength, ultimate shear strength and cumulative dissipated energy can be significantly increased. The paper therefore presents the background, procedure and set-up used as well as the test results.

► Fiber orientation is an important variable on the behavior of the C-SPSWs.
► Failure modes depend on the fiber orientation and the number of GFRP layer.
► GFRP layers can increase cumulative dissipated energy of the C-SPSWs.
► GFRP layers can increase secant stiffness and shear strength of` the C-SPSWs.
► Equivalent viscous damping ratio can be decrease by adding GFRP layer.