Experimental Investigation of the In-Plane Cyclic Behavior of Hybrid GFRP-Steel Reinforced Squat Shear Walls

The susceptibility of steel reinforcement to corrosion undermines the durability of reinforced concrete (RC) elements in aggressive environments. Glass Fiber Reinforced Polymer (GFRP) bars, with superior corrosion resistance and strength-to-weight efficiency, emerge as an optimal substitute. Yet, their cyclic seismic performance remains insufficiently examined. This research investigates the hysteretic behavior of squat GFRP-RC shear walls, hybrid GFRP-steel, and traditional steel bars. Six full-scale wall specimens—two GFRP-reinforced, two hybrid GFRP-steel, and two steel-reinforced controls—underwent quasi-static cyclic lateral loading. Hybrid GFRP-steel walls demonstrated hysteretic stability with negligible residual drift, augmented by boundary elements which significantly bolstered lateral strength and mitigated residual deformations. Furthermore, these walls surpassed their GFRP-only counterparts in energy dissipation efficacy and deformation adaptability, underscoring their advanced seismic resilience in corrosive settings and the critical structural role of boundary elements. This study provides pivotal experimental insights, advocating the integration of GFRP as a viable replacement for steel reinforcement in seismic design, particularly in contexts where corrosion resistance is paramount.