relation: http://eprints.imtlucca.it/3220/ title: On fracture criteria for dynamic crack propagation in elastic materials with couple stresses creator: Morini, Lorenzo creator: Piccolroaz, Amdrea creator: Mishuris, Gennady creator: Radi, Enrico subject: TA Engineering (General). Civil engineering (General) subject: TH Building construction description: The focus of the article is on fracture criteria for dynamic crack propagation in elastic materials with microstructures. Steady-state propagation of a Mode III semi-infinite crack subject to loading applied on the crack surfaces is considered. The micropolar behavior of the material is described by the theory of couple-stress elasticity developed by Koiter. This constitutive model includes the characteristic lengths in bending and torsion, and thus it is able to account for the underlying microstructures of the material. Both translational and micro-rotational inertial terms are included in the balance equations, and the behavior of the solution near to the crack tip is investigated by means of an asymptotic analysis. The asymptotic fields are used to evaluate the dynamic J-integral for a couple-stress material, and the energy release rate is derived by the corresponding conservation law. The propagation stability is studied according to the energy-based Griffith criterion and the obtained results are compared to those derived by the application of the maximum total shear stress criterion. publisher: arXiv date: 2013 type: Working Paper type: NonPeerReviewed format: application/pdf language: en rights: cc_by_nc identifier: http://eprints.imtlucca.it/3220/1/1304.6019v7.pdf identifier: Morini, Lorenzo and Piccolroaz, Amdrea and Mishuris, Gennady and Radi, Enrico On fracture criteria for dynamic crack propagation in elastic materials with couple stresses. Working Paper arXiv (Submitted) relation: http://arxiv.org/abs/1304.6019