Geometrical identification of invisible defects in structural elements basing on digital image correlation data

Abstract

Abstract The paper addresses an experimental-calculational technique intended to determine geometrical parameters of invisible crack-like defects in thin-wall structural elements. Object deformation response to low trial loading is used as baseline data for assessment. The response is recorded using the digital image correlation method. Further analysis consists in minimization of differences between experimental findings and serial model calculations. The description of the approach is carried out on the example of a test specimen in the form of cylindrical shell (tube section) with a non-through crack simulator on the inner surface. The expected displacement fields for different particular cases are calculated using the finite element method.