Discussion: Factored axial compressive resistance of schifflerized angles

Abstract

'paper by Seshu Madhava Rao Adluri and Murty K.S. Madugula. 1991. Canadian Journal of Civil Engineering, 18: 926-932. where A = T(E/F,)~. These values of the normalized slenderness may be used with any appropriate column buckling curve, and give results comparable with those obtained by the authors. However, some questions are raised: 1. The ratio of the minimum moments of inertia for 90 and 60 angles is of the order 1.5: 1. How thick must the section be for the value to be 1.2: 1 as claimed by the authors (p. 926, column 2)? 2. A simple angle has negligible warping stiffness, regardless of the included angle. To what is the 100% increase in warping stiffness attributed, and is it significant? 3. No regard is paid to the various forms of bracing. Would K-bracing be of benefit? 4. To neglect the influence of the root fillet on the area is common practice, but its addition to the torsion constant can be as high as 870, thus its omission makes it difficult to justify the four-significant-figure values given for the buckling loads, and the five-figure precision of the constant in eq. [3]. Perhaps the authors could comment on their superdigitation. ' '