Predicting variability in the dynamic failure strength of brittle materials considering pre-existing flaws
We perform two-dimensional dynamic fracture simulations of a specimen in biaxial tension, incorporating various distributions of pre-existing microcracks. The simulations consider the spatial distribution of flaws while modeling the discrete failure processes of crack interactions and coalescence, and predict the macroscopic variability in failure strength. The model quantitatively predicts the effect (on the dynamic failure strength) of different shapes of the flaw size distribution function, the random spatial distribution of flaws, and the random local resistance to crack growth (i.e. strength) associated with each flaw. The effect of changing material volumes on the variability in failure strengths is also examined in relation to the flaw size distribution. The effect of loading rate on the variability in failure strengths is presented in a form that will enable improved constitutive modeling using non-local formulations at the continuum scale. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: Dynamic strengths ; Finite element method ; Flaw distributions ; Brittle failure ; Crack interactions ; Compressive Strength ; Ceramic Materials ; Damage Evolution ; Silicon-Carbide ; Fragmentation ; Model ; Fracture ; Solids ; Deformation ; Confinement
Record created on 2010-12-01, modified on 2016-08-09