Seismic behavior of steel plate concrete composite shear walls with PEC columns and WRGs

An innovative shear wall was proposed by introducing partially encased composite (PEC) columns and welded reinforcement grids (WRGs) into steel plate concrete composite shear wall. This work conducted an experimental investigation of the seismic behavior of seven 1/3-scale proposed walls subjected to cyclic lateral loading. The design parameters included the forms of distribution reinforcement, axial compression ratio, thickness of the built-in steel plate, shear-to-span ratio and thickness of the PEC column-section steel flanges. The results revealed that the specimens had good bearing capacity, deformation ability, energy dissipation capacity, and stiffness under a reasonable axial compression ratio. Compared with a specimen featuring orthogonal distribution reinforcement, the cracking load and ductility of a specimen with diagonal cross-distribution reinforcement were increased by 6.5% and 13.6%, respectively. And increasing the thickness of the built-in steel plate and the PEC column-section steel flanges could augment the bearing capacity and ensure the late stiffness of the specimens. Then, the residual displacement fitting formulae were presented herein to assess post-earthquake repairability. Besides, the bearing capacity calculation formulae of the novel shear wall with certain prediction accuracy were proposed. Finally, finite element models of the tested specimens were established in ABAQUS and validated with experimental results. Also, further investigations regarding the influence of axial compression ratio and shear-to-span ratio were implemented by finite element analysis and engineering recommendations for the designed axial compression ratio limits of the novel shear were given.