Analytical design solutions for shear buckling of thin plates with edge-stiffened holes

Abstract

This paper studies the elastic shear buckling behaviour of cold-formed steel plates with edge-stiffened central holes of three different shapes (circular, square, and diamond) and proposes simplified approximation formulae for design use. The analysis is conducted utilizing the finite element analysis software ABAQUS through a comprehensive parametric study comprising 4,200 FE simulation models of plates with both edge-stiffened and unstiffened holes over a wide range of plate slenderness ratios and hole sizes. The parametric study investigates the influence of hole geometry with and without edge-stiffeners with key parameters including hole size, plate width, plate length, stiffener size, and plate thickness. The findings reveal that the elastic shear buckling capacity of plates with circular or diamond holes can be substantially enhanced through the inclusion of edge-stiffeners. The edge-stiffeners are shown to recover the elastic shear buckling capacity lost due to perforation and, in many cases, even exceed the initial capacity of unperforated plate. However, for plates with square holes, the addition of edge-stiffeners resulted in only minor improvement in elastic shear buckling capacity. For design purposes, simplified approximation equations for the buckling stress (τcr) are proposed, reproducing the numerical database with COV below 3% for unstiffened perforations and below 10% for edge-stiffened perforations. The proposed formulae are compatible with the ASD/LRFD design formats of ANSI/SDI AISI S100 and AS/NZS 4600, providing a direct and practical means to account for edge-stiffened holes in routine design. A design example is also included in this paper to demonstrate the application of the proposed equations.