In this work two different methods for the detection of cracks in plate structures are presented. In fact, the methods exploit strains measured at different locations on the surface of a structure. Solving the inverse problem, this allows both the identication of crack position parameters, such as length, location and angles with respect to a reference coordinate system and the calculation of stress intensity factors (SIF). First, the solution of the direct problem is obtained e.g. by using the BFM (body force method), substituting the crack by distributed point loads leading to strain fields by superposition of fundamental solutions. On the other hand, the dislocation technique is applied particularly to bounded structures and inclined crack paths. The inverse problem is solved applying the particle swarm optimization (PSO) algorithm. Experiments are performed under cyclic loading using pre cracked plates made of the aluminum alloy Al-7075. (C) 2014 Elsevier Ltd.
