The experimentally determined material toughness of a heavy rolled structural section is linked to the estimation of the critical crack size in the section through an elastic-plastic structural integrity analysis. The assessment methodology is that of the Failure Assessment Diagram (FAD). The fracture model for the section is assumed to be a surface flaw in one flange joined at the flange-web intersection to an edge-flaw in the web. Crack-tip opening displacement (CTOD) toughness values estimated from fracture toughness tests are used in the analysis. Critical surface-flaw depths are estimated for a range of applied stresses with and without rolling residual stresses, and for various surface flaw aspect ratios. The effect of CTOD toughness, applied stress, residual stress and form of FAD on the critical flaw size are discussed.

"Structural Integrity Analysis of a Heavy Rolled Structural Section," presented at the International Institute of Welding Conference on Fitness for Purpose of Welded Structures, Key Biscayne, Florida, October 1991.