The virtual testing of delamination is a goal shared by many practitioners, especially in the aeronautical field. In order to reach such an objective, two research topics which have undergone drastic changes over the last twenty years must be linked: the relevant modeling of composites and the efficient analysis of structures. Indeed, there have been many advances toward a better understanding ...

This paper presents a review of the major fatigue models and life time prediction methodologies for fibrereinforced polymer composites, subjected to fatigue loadings. In this review, the fatigue models have been classified in three major categories: fatigue life models, which do not take into account the actual degradation mechanisms but use S-N curves or Goodman-type diagrams and introduce som...

A damage detection technique, which does not rely on any past baseline signals, is proposed to assess damage in composite plates by using an enhanced time reversal method. A time reversal concept of modern acoustics has been adapted to guided-wave propagation to improve the delectability of local defects in composite structures. In particular, wavelet-based signal processing techniques have bee...

Modeling generic size features of delamination, such as area or length, has long been considered in the literature for damage prognosis composites through specific models describing state evolution with load cycles time. However, delamination shape never considered, despite that it holds important information diagnosis and prognosis, including area, its center, perimeter, useful structural safe...

Delamination is one of the most common failure modes in composite structures. In the case of in-plane compressional loading, delamination of a layered flat structure can cause a local buckling in delaminated area which subsequently affects the overall stiffness of the initial structure. This leads to an early failure of the overall structure. Moreover, with an increase in load, the delaminated ...

The buckling and postbuckling behaviors of a composite beam with single delamination are investigated. A three-dimensional finite element model using the commercial code ANSYS is employed for this purpose. The finite elements analyses have been performed using a linear buckling model based on the solution of the eigenvalues problem, and a non-linear one based on an incremental-iterative method....

Compressing a thin elastic film attached to a thick compliant substrate can lead to buckling instability. Two commonly observed buckling modes, buckle-delamination and wrinkling, have each been analyzed separately in previous studies. Recent experiments have observed that the two modes can co-exist and co-evolve. In this paper, by analytical and finite element methods, we present a study on con...

This paper presents a study on active detection of internal damage based on numerical analysis of vibration dynamics in composites. Damageinduced variations of dynamic parameters are investigated both numerically and experimentally. Finite element method (FEM) is used to compute the modal parameters of composites with or without damages. Natural frequency, modal displacement, modal strain and s...

We consider the buckle-driven delamination of compressed thin lms. For a wide class of patterns of delamination, it is shown that the loading on the delamination front progressively goes from mode I to mode II during growth of the blister. As a result, the mode dependence of the lm/substrate interface excludes widespread delamination. This explains the observations of blisters of nite extent, w...

Delamination detection in the composite structure based on the vibration responses when excited at the lower modes has been suggested here. It has been observed that the nonlinear interaction between the delaminated layers produce higher harmonics of the exciting frequency. These higher harmonics have observed to be useful for the detection and location of the delamination without comparing the...