Morphogenesis and propagation of complex cracks induced by thermal shocks

Blaise Bourdin, Department of Mathematics and Center for Computation & Technology, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
Jean-Jacques Marigo, Laboratoire de Mécanique des Solides (UMR-CNRS 7649), École Polytechnique, 91128 Palaiseau Cedex, France.
Corrado Maurini, Institut Jean Le Rond d'Alembert (UMR-CNRS 7190), Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris, France and Institut Jean Le Rond d'Alembert (UMR-CNRS 7190), CNRS, 4 Place Jussieu, 75252 Paris, France.
Paul Sicsic, Laboratoire de Mécanique des Solides (UMR-CNRS 7649), École Polytechnique, 91128 Palaiseau Cedex, France and Lafarge Centre de Recherche, 95 Rue de Montmurier 38290 St-Quentin-Fallavier, France.

Abstract

We study the genesis and the selective propagation of complex crack networks induced by thermal shock or drying of brittle materials. We use a quasistatic gradient damage model to perform large-scale numerical simulations showing that the propagation of fully developed cracks follows Griffith criterion and depends only on the fracture toughness, while crack morphogenesis is driven by the material's internal length. Our numerical simulations feature networks of parallel cracks and selective arrest in two dimensions and hexagonal columnar joints in three dimensions, without any hypotheses on cracks geometry, and are in good agreement with available experimental results.