Hybrid micromechanical-phenomenological modelling of anisotropic damage and anelasticity induced by micro-cracks in unidirectional composites

Abstract

Fodil Meraghni. Hybrid micromechanicalphenomenological modelling of anisotropic damage and anelasticity induced by micro-cracks in unidirectional composites.Composite Structures, Elsevier, 2017, 182, pp.223-236. 10.1016/j.compstruct.2017

Hierarchical micromechanical modeling of the viscoelastic behavior coupled to damage in SMC and SMC-hybrid composites

“…Similar approximation has been considered in Praud et al (2017) and the comparisons with experimental data showed excellent accuracy in the direction parallel to fibers, and quite satisfactory representation of the response normal to the fibers direction. This observation permits to simplify this step of homogenization, by assuming that, only for this case, the matrix also behaves elastically inside the bundle before damage occurs.…”

“…Damage can appear at the matrix phase, at the interfaces between matrix and fibers or matrix and bundles, or at the fibers themselves. As mentioned in the introduction, this work attempts to integrate damage that is observed at the level of the bundles by using a hybrid phenomenological-micromechanical model, developed by Praud et al (2017). It should be pointed out that the damage model in this work is a "brick" that can be easily interchanged with another damage model.…”

“…It should be pointed out that the damage model in this work is a "brick" that can be easily interchanged with another damage model. Since the Praud et al (2017) damage law is quite complicated and has already been published elsewhere, only the general description of the model is presented here. In fact, this constitutive law for fiber bundles has been experimentally validated in natural fibers multi-directional laminate composites.…”

“…Damage mechanisms in this type of composites can occur at different levels (matrix, fibers, fiber bundles, interfaces) and they can be taken into account with various ways (Fitoussi et al, 1998;Derrien et al, 2000;Morozov et al, 2003;Jendli et al, 2004Jendli et al, , 2009. In this study, it is chosen to incorporate damage at the glass bundles using a recently developed hybrid phenomenological-micromechanical model (Praud et al, 2017).…”

“…Microcracks are initiated due to the debonding of the fiber-matrix interface and propagate by coalescence. The hybrid model of Praud et al (2017) considers that initially the unidirectional composite is elastic, whose elasticity tensor C 0 is provided by any micromechanics approach (in this work the CCM is considered for the bundles). Then, as the loading increases, penny-shape micro-cracks start to be formed ( Figure 5).…”