In the first part of this study, strains under hydrostatic pressure in an elastic and isotropic body containing a number of penny-shaped microcracks were theoretically investigated to clarify the physical meaning of the parameters used in Differential Strain Curve Analysis (DSCA) and then, a new parameter was proposed to reduce the effects of anisotropy in the intrinsic linear compressibility on the evaluation of crack density.
In the second part of this study, the effects of loading methods were experimentally investigated first and the results in the third loading cycle were proposed to be used to evaluate microcracks in rock. Then the parameters characterizing microcracks were determined for some rocks by DSCA. The results showed that better reproducibility was obtained by the new parameter, (Δβ/βl) I, and that microcracks in a soft and porous sedimentary rock can be evaluated by DSCA if the maximum pressure is chosen so that the pressure does not cause new microfracturing in the rock.
