Development of a New Methodology for Delamination Detection in Laminated Structures

Abstract

A new methodology to study the behaviour of delaminated composite structures has been developed. This study can be split up into two parts: The first one is about the detection of delamination in damaged laminated thin structures. In the finite element computational code, those laminated structures are modelled using shell elements. The methodology uses post-process criteria based on fracture mechanics linked with damage mechanics of computational code by the effective stress tensor. In the second place, the influence of delamination over the overall behaviour of the structure is taken into account. This influence is introduced by locally changing the material characterisation, progressively during the loading phase. These integrated effects change the numerical behaviour on loading and energy curves. Experimental validation studies are carried out in static tension tests, static and dynamic tests and low velocity impact with a spherical tool. The comparison between experimental and numerical results allows us to conclude to a good correlation and to the validation of this methodology. Many perspectives appeared at completion of this work.