The paper will present recent results obtained as part of the EU FP5 project “Enpower — Management of Nuclear Plant Operation by Optimised Weld Repair”
concerning the effect of residual stress load-history on fracture. This paper concentrates on the behaviour of A533B low alloy ferritic steel. A companion paper concentrates on type 316H austenitic stainless steel. The rationale of the research was to validate advanced numerical modelling techniques with an experimental fracture programme. In order to achieve this, a laboratory test specimen was required which contained a well-defined residual stress field. This would enable complementary numerical and experimental fracture programmes to proceed in parallel. The paper therefore begins with a description of the mechanism developed to generate residual stress fields in beam specimens. The paper will then show numerical predictions of the residual stress state in the beam specimens, details of the numerical fracture modelling, the experimental fracture test results, and will conclude by discussing the comparison of experimental results and predictions.