Determining the petrographic fabric of a compacted soil using semivariance analysis: sample preparation and digital petrographic image analysis

Samples from compacted soil have been prepared for scanning electron microscopy (SEM) using a technique that has been developed in order preserve the property under investigation. Using the SEM images, digital image analysis has been used to estimate semivariograms for the pore space of a compacted artificial soil. Strain ellipses quantifying the degree of heterogeneity have been constructed using the structural information provided by the semivariograms. The results show that the physical response of the pore space depends on pore size. In the case of the artificial soil, investigated here, two structural regimes were found to exist at two different scales.