Seismic Response and CFRP Retrofit of Poorly Detailed Shear Walls

Abstract

The reversed cyclic loading behavior of full-scale shear wall specimens was investigated before and after retrofit. The wall specimens were designed and detailed to simulate nonductile reinforced concrete construction of the 1960s, having lap splices of the longitudinal reinforcement in the potential plastic hinge region, and having inadequate confinement of the boundary regions. The lap splices in these walls failed in a brittle manner before yielding occurred in the main flexural reinforcement. The use and effectiveness of carbon fiber-reinforced polymer (CFRP) wrap for improving the lap splice behavior and the shear strength of the walls were investigated. The walls were tested under reversed cyclic loading with loading applied near the tip of the walls. The retrofit technique improved the displacement ductility, energy dissipation, and prevented premature failure of the lap splices. The target ductility level of 2.0 was achieved with this CFRP retrofit.