Effect of Compaction Banding on the Hydraulic Properties of Porous Rock: Part I-Experimental Investigation

The mechanical behavior and the influence of compaction banding on the hydraulic properties in soft porous rocks were studied. The tested rock was Calcarenite Tuffeau de Maastricht. In the frame of experimental investigations, triaxial and oedometric tests were conducted under dry and drained conditions. The results demonstrated that the rock is forming discrete compaction bands under high confining stresses and steep angle shear bands under low confining stresses. Permeability measurements during the oedometric and triaxial compression tests under drained conditions demonstrated that the axial permeability decreases with increasing axial strain. The maximum permeability decrease was three orders of magnitude for 40% of axial strain.

Automated summary

Experimental studies on soft porous rocks showed that discrete compaction bands form under high confining stresses, while shear bands form under low confining stresses. Axial permeability decreases with increasing axial strain, with a maximum permeability decrease of three orders of magnitude at 40% axial strain.