Experimental Investigation of the Mechanical Behavior and Permeability of 3D Printed Sandstone Analogues Under Triaxial Conditions

Consolidated drained triaxial tests arise as one of the most exhaustive methods to quantify the strength, volumetric behavior and failure process of rocks. Understanding the compressibility of a rock matrix and the permeability evolution induced by the effects of confining stress is essential to achieve a better understanding of the productive behavior and performance of enhanced hydrocarbon recovery methods in natural reservoirs. This study investigates the suitability of using of reservoir sandstone analogues, 3D printed with silica sand, to analyze the behavior of natural rocks. A comprehensive mechanical and hydraulic characterization of 3D printed silica sand is addressed by subjecting the sandstone analogues to various levels of confining stress and measuring their cumulative volumetric deformation and permeability evolution at each compression stage. Experimental results demonstrate that 3D printing technology can reproduce porous media that resembles the mechanical behavior of natural reservoir rocks. Nonetheless, some divergences are encountered with the properties of 3D printed analogues when compared to natural reservoir rocks. The 3D printed sandstone analogues were found to be more compressible and permeable than widely studied reservoirs such as Berea Sandstone. Efforts are made to optimize the 3D printing process of the rock analogues to overcome the differences encountered in the mechanical and hydraulic behavior.