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In this study, three-dimensional simulations of cone penetration tests (CPT) in cemented sandstone have been carried out using the Discrete Element Method (DEM). The particle size distribution of the sandstone analogue samples from the Ustyurt-Buzachi Sedimentary Basin was replicated with the numerical samples. Numbers of numerical CPT tests at different bond strength values were performed with the penetrometer vertically moved down at a constant rate. The results of the real-world particle size distribution show that the cone penetration resistance and sleeve friction increase with increasing depths; and with increase in bond strength the cone resistance and side friction decrease, while the friction ratio increases. The result of numerical CPT tests in cemented sandstone was found to be in good agreement with the Soil Behaviour Type (SBT) classification system from CPT data.

In this study, three-dimensional simulations of cone penetration tests (CPT) in cemented sandstone have been investigated using the Discrete Element Method (DEM). We generated the realistic grain size distribution of sandstone in the numerical simulations using the Ustyurt-Buzachi Sedimentary Basin samples. Numbers of numerical CPT tests at different bond strength values were performed with the penetrometer vertically moved down at a constant rate. The results of the real-world particle size distribution show that the cone penetration resistance and side friction increase with increasing depths; and with increase in bond strength the cone resistance and side friction decrease, while the friction ratio increases. The result of numerical CPT tests in cemented sandstone was found to be in good agreement with the Soil Behaviour Type (SBT) classification system from CPT data.

Three-dimensional CFD-DEM-IBM simulations of sand production in a sandstone formation, using periodic boundaries, were performed using 10000 frictional elastic spheres bonded together and compressed at 1 MPa of overburden pressure. Sand production simulation geometry and procedure are proposed, in which the cone penetration test (CPT) has been used to investigate a physical perforation penetration of the cemented sandstone material with the real-world grain size distribution from the Ustyurt-Buzachi Sedimentary Basin. The Immersed Boundary Method (IBM) was adapted for the sand production simulation geometry to simulate the fluid flow near the well casing. Oil with low viscosity and density was used as an injection fluid (reservoir fluid). Erosion near the perforation tunnel due to the pressure drawdown was examined, where the production of sand particles was initiated during the first flow due to the drag force that lifted the sand particles from the perforation damage zone. At the beginning of the simulation a sand arch was captured around the perforation tunnel and due to the fluid flow it collapsed and perforation cavity became larger. The amount and mass of produced sand particles were calculated.