Based on the traditional definitions associated with creep strain accumulation in defect free components, a generalised definition for “elastic follow-up” factor, Z is proposed that characterises the impact of a “nonlinear” event experienced locally within a structure, i.e. creep, plasticity, cracking, growth of an existing crack -or any combination of such events- on the response of structure to the applied loading. A “crack affected zone” approach is then outlined for evaluation of this parameter in a defected component. The significance of quantifying elastic follow-up in relation to integrity assessment procedures and the challenges facing its practical implication to the codes is discussed. The approach is finally examined through its application to two example problems; a standard test geometry, centre cracked plate (CCP) and an external circumferential cracked thick cylinder (ECCC) i.e. a conventional structural component.

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