On optimum perforation layout in low-rise steel plate shear walls.

The design and performance of Steel Plate Shear Walls (SPSW) strongly depends on infill panels. Any unnecessary increase in the thickness of infill panels, which is a common occurrence in low-rise buildings, results in extremely large boundary elements and a noneconomic design. Among the several remedies that have been proposed and discussed by researchers, infill panel perforation has become more popular in SPSW design and construction. As a designer, one should primarily choose a desirable perforation layout, then adopt an approximate stiffness reduction formula and try to replace the infeasible design infill panel with a perforated one which possesses a minimum practical thickness and provides a similar lateral stiffness and strength. In this paper for a 4-story SPSW, primarily designed with practically infeasible thin infill panels, the optimum perforation diameters corresponding to diverse diagonal and rectangular perforation layouts are explored and the results have been compared to those provided by the available stiffness reduction formulas. The optimization outcomes reveal that the uniformly spaced rectangular perforation layouts are more efficient in the sense of SPSW stiffness reduction. Also, the efficiency of stiffness reduction formulas for rectangular perforation layouts have been assessed and the reliable methods introduced. Finally, on the basis of the resulted optimum sets, some formula improvements and design recommendations are concluded which would be useful and beneficial for practicing engineers.