The Brittle‐Ductile Transition in Porous Limestone: Failure Mode, Constitutive Modeling of Inelastic Deformation and Strain Localization

Understanding of the mechanics brittle-ductile transition (BDT) in porous limestone is significantly more challenging than for sandstone because lack consistent acoustic emission activity limestone, meaning that one must rely on alternative techniques. In this paper, we investigate systematically failure modes Indiana using X-ray microComputed Tomography imaging (μCT) and Digital Volume Correlation (DVC). Our new mechanical data show envelope onset shear-enhanced compaction can be well approximated by an elliptical cap. The DVC analysis revealed development shear bands through BDT, but no evidence bands. band angles were between 29° 46° with respect to maximum principal stress. Compiling these results published Purbeck Leitha limestones, showed inelastic each dual porosity allochemical limestones was a good agreement normality condition, as defined plasticity theory. Comparison observed predictions based bifurcation are consistently smaller theoretical predictions.