Structural Integrity of Dissimilar Welds: ADIMEW Project Overview

The objective of the ADIMEW project, that follows BIMET program finished in 2000, is to contribute to the development and verification of analysis methods which describe the behaviour of an external circumferential defect at the surface of a Dissimilar Metal Weld (DMW). The complexity of the problem results from the prevailing mixed-mode loading conditions, the variation in material constitutive equations across the weld zone, and the presence of large residual stress field. Under these circumstances, classic fracture mechanics concepts are difficult to apply. Recently different cracks has been discovered in different US and European plants (VC SUMMER, RINGHALS, BIBLIS). The problem of integrity of aged (cracked) DMW’s remains an important safety issue. This paper presents the new on-going program ADIMEW, with similar organisation than BIMET and complementary objectives. Within the framework of this project, one large test has been successfully done on July 2003. The paper presents a general overview of the program and the major recommendations and conclusions.