Seismic behavior of steel plate and reinforced concrete composite wall coupled to steel side columns

Abstract

The steel plate and reinforced concrete (SPRC) composite wall coupled to steel side columns is a new type of coupled system, which consists of a single SPRC composite wall coupled to steel side columns through steel coupling beams at all floors. One 1/4 scaled five-story SPRC composite wall coupled to steel side columns with a plastic coupling ratio (CR) of 0.45 was designed, constructed, and tested under simulated earthquake action. The test results exhibited great seismic performance of the proposed coupled system with the coupling mechanism fully developed. The average displacement ductility coefficient was 3.12. And the average values of the inter-story drift ratio of all stories at the yield, peak load, and ultimate conditions were 1.32%, 2.55%, and 3.70%, respectively, showing good inter-story deformation capacity. The average ultimate plastic shear rotations of steel coupling beams at the 2nd, 3rd, 4th, and 5th floors were 0.0211 rad, 0.0364 rad, 0.0556 rad, and 0.0913 rad, respectively, indicating great energy dissipation contributions of the steel coupling beams. The steel side columns remained elastic under shear forces transmitted from steel coupling beams through hinge joints and provided a stable overturning moment resistance to protect the SPRC wall. The accuracy of the test results was verified against the numerical analysis results. The parametric analyses were conducted to further the understanding on the influences of key design parameters on the seismic performance of the proposed coupled system. The peak lateral load can be enhanced by increasing the axial load or steel plate ratio. In order to obtain good energy dissipation capacity and ductility, a moderate value of 0.15 for the axial load ratio or 6.6% for the steel plate ratio can lead to excellent deformation capacity.