Failure Process Characterisation of a Limestone from Deterministic Models

Summary¶About 30 uniaxial and triaxial compression tests have been conducted on a dry, porous and homogeneous limestone. Compressional and shear waves were propagated both in the axial and radial directions. From the accurate determination of velocities, effective medium theories are used to model effective moduli of this rock in terms of the properties of their different elements. Three deterministic models are applied after Tourenq and Denis, O'Connell and Budiansky and Soga et al. By estimating crack density parameters as a function of stress or strain up to rupture, these models indicate that an interpretation in terms of closure-opening-creation of cracks is valid. It is concluded that the application of the model of Soga et al. provides an easy and pragmatic scheme to characterise the failure process of the limestone tested under dry conditions.

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