Column demands in steel plate shear walls with regular perforations using performance-based design methods

• Standardized method presented to evaluate seismic-zone independent target displacement.
• The perforations may not reduce the net force and deformation demands on the columns.
• Minor change in perforation pattern may cause significant differences in column moment demand.

The design force demands on the columns of steel plate shear walls tend to be very large. Several methods have been proposed to reduce the moments and axial forces on the columns, while still achieving good system performance. One such method is to reduce the strength of the infill plate by perforating it using a regular pattern of circular holes. The diameter of the holes selected and their center-to-center spacing control the decrease in lateral shear strength of the system. An appropriate performance-based design method is proposed and used to study the suitability of the perforated system. The results of a variety of finite element models showed that although introducing the perforations into the infill plates reduces the lateral strength of the system, the net demand on the columns can in some cases actually increase. The perforated system behavior is also sensitive to the pattern of holes selected; a small change in the arrangement of the holes can have a significant effect on the moment demand on the columns. Also, the flexibility of the beam-to-column connections influences the sensitivity of the column design forces to the pattern of holes selected and affects the column demands considerably.