A Computational Model for Predicting Damage Evolution in Laminated Composite Plates

Abstract

A model is developed herein for predicting the evolution of interface degradation, matrix cracking, and delamination at multiple sites in laminated continuous fiber composite plates subjected to monotonic and/or cyclic mechanical loading. Due to the complicated nature of the many cracks and their interactions, a multi-scale micro-meso-local-global methodology is deployed in order to model all damage modes. Interface degradation is first modeled analytically on the microscale, and the results are homogenized to produce a cohesive zone model that is capable of predicting interface fracture. Subsequently, matrix cracking in the plies is modeled analytically on the meso-scale, and this result is homogenized to produce ply level damage dependent constitutive equations. The evolution of delaminations is considered on the local scale, and this effect is modeled using a three dimensional finite element algorithm. Results of this analysis are homogenized to produce damage dependent laminate equations. Finally, global response of the damaged plate is modeled using a plate finite element algorithm. Evolution of all three modes of damage is predicted via interfacing all four scales into a single multi-scale algorithm that is computationally tenable for use on a desktop computer. Results obtained herein suggest that this model may be capable of accurately predicting complex damage patterns such as that observed at open holes in laminated plates.

Method for Performing Accelerated Characterization of Viscoelastic Constitutive Behavior of Asphaltic Concrete

“…Therefore, the model described can be used as a design tool for improving roadway life at considerable cost savings to the public. Indeed, this process has been previously used by the second author in a variety of other structural applications (Foulk et al 1998;Helms et al 1999;Phillips et al 1999;Allen et al 2001a). The application of this design procedure to asphaltic roadways will be the subject of a future paper by the authors.…”

Multiscale model for predicting damage evolution in composites due to impact loading

“…Fortunately, there are few problems of current technological significance that require more than about three computational scales (there is generally no limitation on the number of analytic scales, as these require little computation; but analytic solutions, unlike the cohesive zone model described in the previous section, are not often attainable). Allen and coworkers have been able to obtain solutions on a desktop computer by this technique using as many as four length scales simultaneously, although it must be admitted that two of these scales were analytical [25].…”

Some effects of viscoelasticity on ability to model failure in composites

“…Allen and coworkers have been able to obtain solutions on a desktop computer by this technique using as many as four length scales simultaneously, although it must be admitted that two of these scales were analytical. 21 Crack modelling at local length scale Crack propagation is herein modelled by using a cohesive zone model because this type of fracture mechanics model is more convenient to be utilized in computational algorithms and for modelling multiple cracks simultaneously. More specifically, we use the micromechanical viscoelastic cohesive zone model developed by Allen and Searcy.…”