Modifying the Shear Buckling Loads of Metal Shear Walls for Improving Their Energy Absorption Capacity

In this paper, an approximate method is proposed for achieving predefined increases in the buckling threshold of a metal shear wall in order to increase its energy absorption capacity. The first and second-order derivatives of shear buckling loads of a shear wall with respect to the thickness in its different regions are calculated. Based on these eigenderivatives, and by using the first and second order Taylor expansions, the necessary change in the thickness of plate in various regions is calculated for increasing the shear buckling loads by a specific value. The presented modification algorithm is implemented for shear walls with different aspect ratios, material properties and boundary conditions. An initial sensitivity analysis is carried out for finding the regions within the shear wall where modifying the thickness has the most influence on the buckling loads. Based on the sensitivity analysis results, appropriate regions of plate are selected and the necessary modification in thickness of these regions is calculated for achieving a relatively large predefined change in shear buckling load. By simulating the post-buckling response of both initial and modified plates in a case study, the improvement in the energy absorption capability of the modified plate is also studied.