POSTBUCKLING BEHAVIOR OF STEEL-PLATE SHEAR WALLS UNDER CYCLIC LOADS

In current design practice the capacity of a steel-plate shear wall is limited to the elastic buckling strength of its plate panels. This practice results not only in a conservative design, but also in an undesirable one where the columns yield and may buckle before the plate reaches a fraction of its capacity. Plate buckling is not synonymous with failure and if the plate is adequately supported along its boundaries, as in the case of the shear wall, the postbuckling strength can be several times the theoretical buckling strength. Furthermore, due to the unavoidable out-of-plane imperfections, no change in the plate behavior will be observed at the theoretically calculated buckling load. Although the post-buckling behavior of plates under monotonic loads has been under investigation for more than half a century, this behavior under cyclic loading has not been investigated until recently. One test was conducted at the University of Alberta and 10 tests were conducted at the University of Maine. In this paper analytical models are described. These models are capable of accurately predicting the behavior of the wall in the postbuckling domain under monotonic and cyclic loads.