Date of Award


Degree Type


Degree Name

Master of Science in Civil Engineering


Washkewicz College of Engineering

Subject Headings

Civil Engineering, Engineering


Steel plates are planar structural elements with one dimension significantly smaller than the others. These elements may fail due to either material yielding or buckling. Buckling is a sudden failure mode, which is not desirable in structural engineering applications. Buckling is called an “elastic buckling” when it happens before material yielding, and is termed as “plastic buckling” if it happens after material yielding. The focus of this thesis is on shear plates, which are plates that are primarily subjected to shear loads. Several studies were conducted to increase the elastic buckling capacity of plates by adding stiffeners to plates. However, the research appears inconclusive as to whether the overall behavior of the plate will change so that buckling will happen after yielding (i.e., changing elastic buckling to plastic buckling).

The aim of this thesis was to analyze the performance of simply supported shear plates with and without stiffeners and determine whether a behavior change is possible by adding stiffeners. For this purpose, a variety of plates were studied by measuring the elastic critical buckling load and the yielding load to evaluate plate performance. A parametric study was conducted with varying plate slenderness ratio, initial imperfection magnitude and pattern, and number and the arrangement of the stiffeners. This resulted in 42 separate plate models that were analyzed using a non-linear finite element analysis with the ABQUS software. It was found that adding stiffeners to a steel plate can change plate overall behavior. This is manifested by reducing the difference between the elastic critical buckling load and the yielding load until buckling load is greater than yield load, which changes the plate behavior from slender to stocky plate. Furthermore, it was found that stiffener design is a critical criterion. Overdesigning stiffeners may lead to local yielding in plates which precludes the attainment of the intended capacity.