We explored the frictional properties of 3D-printed sand interfaces and we created 3D fault analogs for earthquakes. Our results are summarized in a recent paper in JGR. https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JB020520?af=R https://www.researchgate.net/publication/349734697_Design_of_sand-based_3D-printed_analogue_faults_with_controlled_frictional_properties
