2017 Annual Stability Conference Presentation
Session S10 – Stability of Plates
Friday, March 24, 2017
Postbuckling Mechanics of Square Slender Steel Plates in Pure Shear: Examining the Role of Second Order Effects
Slender steel plates possess strength beyond the elastic buckling load, which is commonly referred to as the postbuckling capacity. In current practice, postbuckling mechanics of slender web plates under pure shear loading in bridge girders are characterized by semi-empirical approaches whose origins date back to experimental tests in the 1960’s. To date, however, the postbuckling mechanics of these plates are still not fully understood, and this paper therefore explores such fundamental behavior. Using finite element analyses (which are validated against available results of previous tests), outputs such as von Mises stresses, principal stresses, and principal stress directions are examined on both surfaces of a buckled slender plate acting in pure shear. The internal bending, shear, and axial stresses in the plate’s finite elements are evaluated for a simply-supported plate with aspect ratio equal to 1.0 and slenderness equal to 134 – future work will examine a wider range of plate parameters. Results show that localized bending in the plates due to the out-of-plane postbuckling deformations (right contour plot, MPa) are significantly larger than the in-plane membrane stresses (left contour plot, MPa). Bending thus appears to be a significant factor in the ultimate shear buckling capacity of the plate. Also, the compressive stresses continue to increase beyond elastic buckling in some regions of the plate, contrary to current design assumptions.
Maria E. Moreyra Garlock, Princeton University, Princeton, NJ; Spencer Quiel, Lehigh University, Bethlehem PA; José Alós Moya, Universitat Politècnica de València, Valencia, Spain; Jonathan Glassman, Exponent Failure Associates, Los Angeles, CA