THE TREATMENT OF COMBINED PRIMARY AND SECONDARY STRESSES IN ELASTIC-PLASTIC AND CREEP FRACTURE

摘要

This paper examines a range of secondary stresses from those that may need to be treated as primary to those which are relaxed rapidly by inelastic straining. Methods are developed for the former case such that, rather than treating these secondary stresses as primary in an assessment, an upper bound correction may be used with existing procedures for secondary stresses. For other cases, less conservative approaches than those in existing fitness-for-service procedures are presented for both the elastic-plastic and creep regimes. The approaches presented are supported by finite-element analysis results for a range of cases.