Seismic Behavior of Precast Concrete Shear Walls with Different Confined Boundary Elements

Abstract

To ensure the mechanical property of lapped spliced reinforcement and concrete confinement of boundary elements for precast concrete shears, two kinds of constraints, local constraint by additional spiral stirrups placed around each reinforcement splicing and overall constraint by lapped welding closed stirrups replacing traditional stirrups and ties, were proposed in this paper. Low-cyclic reversed loading tests were conducted on three full scale specimens, including one reference cast-in-situ specimen, one precast concrete specimen with local constraint and one precast concrete specimen with overall constraint. By comparing the aspects of strength, stiffness, ductility and energy-dissipation capacity with that of cast-in-situ specimen, it is found that local constraint and overall constraint can be considered equivalent. However, due to the over restraint by local constraint detail, the specimen with local constraint exhibited earlier yielding, poorer energy-dissipation capacity and better ductility than that with overall constraint. Coupled with the consideration of steel usage and construction simplicity, overall constraint detail should be preferred in practical engineering.