Multiscale simulation of delamination in composite laminates

This work makes use of the cohesive zone models developed in LMT Cachan by Prof. Allix. [Allix et al. 1992] to simulate inter-laminate crack propagation. The LaTIn domain [Ladeveze et al. 2002] decomposition solver permits to handle the nonlinear interface constitutive law efficiently. In a nutshell, the cohesive behaviour is lumped into the interfaces of the domain decomposition method. The resulting problems for each substructure are linear and can be factorised once for all at the start of the simulation. However, this process raises difficulties. The convergence rate of the iterative algorithm of the LaTIn domain decomposition approach is affected by the damage state of the cohesive interfaces. One of the major contribution of the work was to adapt this algorithm to the local nonlinearities, which enabled to retrieve the expected numerical efficiency [Kerfriden et al. 2009].

The very rich coarse scale problem of the LaTin domain decomposition method limits the scalability of the method. A Schur-based domain decomposition solver is developed to overcome this limit [Kerfriden et al. 2009].