The objective of the three-year ADIMEW project, which started in November 2000, was to contribute to the development and verification of analysis methods that describe the behaviour of cracked dissimilar metal welds (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 fields. Under these circumstances, classic fracture mechanics concepts are difficult to apply.
The project had the following technological and scientific aims:
- Quantify the accuracy and conservatism of structural integrity procedures used by the nuclear industry in Europe to predict the behaviour and assess the safety of circumferential defects at the surface of dissimilar metal welds
- Perform a unique verification of the load-carrying capacity of an industrially representative cracked DMW under operating conditions in a large-scale structural test. To do this, a special assembly was prepared, with circumferential cracks introduced into the surface of a dissimilar metal weld between low-alloy steel and austenitic steel pipes with a diameter of 450 mm
- Rapidly disseminate the results for the benefit of operators, regulators and research organisations in Europe, in collaboration with the Network for Evaluating Structural Components (NESC).