Abstract：To improve the seismic behavior of coupling beams of conventional shear wall in high-rise buildings, three embedded steel plate reinforced concrete composite coupling beams (SPC) and one diagonally reinforced coupling beam was tested under cyclic loading. The variable parameters in tests include longitudinal reinforcement ratios and steel plate forms. The failure process, hysteretic behavior, energy dissipation, strength and stiffness degradation, bearing capacity, ductility and deformation performance were investigated. The failure modes of specimens include bending-shear and bending. Test results indicate that as longitudinal reinforcement ratio of coupling beam increases excessively, the bearing capacity of core walls may increase, but the ductile deformation may reduce. At the same plate ratio, the two specimens embedded with single plate and double decker plate have similar strength and deformation performance. In practice, double decker plate instead of single thick plate can be designed when the thickness of single plate is too large. It was found that embedded steel plates could improve the strength and the ductility of coupling beams. Compared with diagonally reinforced coupling beam, the pinch phenomenon of hysteretic curves was improved obviously. The plate provides greater capacity to resist the bending moment, and enhance rotation capacity of plastic hinge. Consequently, concrete composite coupling beams embedded with steel plate have more stable hysteretic performance and greater energy dissipation capacity, and can be constructed conveniently. Integrated seismic behaviors of SPC coupling beams are superior to those of diagonally reinforced coupling beams.
