| dc.description.abstract | Using 3D printing technology, fracture conductivity test samples are replicated to overcome the challenge of sample inconsistency. The fracture surface topography is acquired using a laser profilometer, CT scans, and photogrammetry techniques. The
developed and printed 3D models are used to make concrete replicates of cement/shale and cement/sand mixtures.
We validate the replicability of these samples based on visualized scans of the fracture surface of the original rock samples, 3D molds, and concrete replicates. The joint roughness coefficient is also used to quantify and validate the replicability of these samples. The replicability ranged from 78% to 99% for the Meremac core using CT scans and DLP printer, and from 75% to 93% for the Austin chalk core using photogrammetry technique and FDM printer. The fracture conductivity results were used as the final check for replicability. The cement/sand mixture replicate C5 and C7 which were cured for relatively similar conditions produced very similar fracture conductivity results.
Based on these results, we stipulate that 3D printing can be applied for fracture conductivity testing to replicate fracture surfaces and experimentally investigate factors that contribute to fracture conductivity. Mechanical properties and surface topography of
rock samples dominate fracture conductivity behavior especially at closure stress within the peak strength of the rock sample.
This study is important because the consistency of fracture conductivity samples will provide valuable insights into experimental studies on hydraulic fracturing. The effects of surface topography, proppant distribution, grain size distribution, fluid carrying ability of fracturing fluids, and several other factors that affect fracture conductivity can now be qualitatively investigated. | en |
