Seismic Response of Fiber-Reinforced Concrete Coupled Walls

Abstract

The behavior of coupled T-shaped structural walls was studied through tests of two large-scale four-story specimens under reversed cyclic lateral displacements. The use of tensile strainhardening, high-performance fiber-reinforced concrete (HPFRC) in coupling beams and walls was evaluated as a means to reduce diagonal and confinement reinforcement. The Specimen CW-1 walls were constructed with reinforced concrete (RC) designed to satisfy ACI Building Code (ACI 318-08) seismic provisions. The walls in Specimen CW-2 were constructed with HPFRC and reduced shear and confinement reinforcement. Each specimen included one RC and three HPFRC precast coupling beams with span-depth ratios of 1.75. Both specimens sustained 80% of the peak lateral strength through loading cycles to at least 2.5% drift. Inelastic flexural deformations were more concentrated near the foundation in the HPFRC walls than in the RC walls, which led to a higher curvature demand at the base of the HPFRC walls. Although the walls in both specimens exhibited a flexuraldominated behavior, shear distortions in the first story of the walls reached 0.01 rad. Detailed data are presented regarding specimen behavior, including wall and coupling beam deformations.