The influence of residual stresses on the fracture behaviour of materials is of fundamental importance for accurate and reliable structural integrity assessments of components and structures In this paper residual stress fields are introduced into standard fracture specimens, particularly C(T) specimens, through ‘local compression’, or side punching. Finite element analysis showed that tensile residual stresses could be generated ahead of the crack, but their magnitude was very sensitive to the position of the punch relative to the crack tip when a single punch was used on each side of the component. Experimental results indicated differing amounts of reduction of the apparent fracture toughness in the presence of residual stresses following local compression for different materials. The method of application of local compression was then extended to the application of a double punching tool. A parametric study revealed that the size and the position of the punching tools had a strong influence on the magnitude and direction of the residual stress field.

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