Original Paper(Vol.56 No.6 pp.544-549)

Reliability Based Defect Assessment Methodology for Welded Joints with Respected to Brittle Fracture

Norio YAMAMOTO, Ryosuke MURAI and Hitoshi YOSHINARI

Abstract:Using the reliability approach such as an advanced first order secondmoment method (AFOSM), FTS Committee organized in the Japan Welding Engineering Society (JWES) hasdiscussed the defect assessment methodology which employs the partial safety factors forcharacterized defect size, applied strain and fracture toughness to warrant the reliability of the welded structures with respect to brittle fracture. This paper describes the procedure of introducing reliability approach to the JWES2805 standard and the partial safety factors are evaluated to secure the expected reliability. This methodology is to be adopted in the revised JWES standard 2805 "Method of assessment for flaws in fusion welded joints with respect to brittle fracture and fatigue crack growth".

Key Words:Reliability, Fracture toughness, Partial safety factor, JWES2805 standard, Defect assessment