Predissolution and postdissolution penetration resistance

Mineral dissolution is a common chemomechanical digenetic process in geological systems. The penetration resistance in sediments that have experienced dissolution is studied using a laboratory-scale cone penetration test device and a calibration chamber. Variables include the initial sediment density and mass fraction of soluble grains. Results show that the void ratio increases with the extent of mineral dissolution; the magnitude of the void ratio change is higher in initially dense sediments. A terminal void ratio is found for dissolution; the void ratio after dissolution will not exceed this terminal void ratio regardless of the extent of dissolution. For boundary conditions applied in this study, the terminal void ratio for dissolution corresponds to a relative density of Dr ≈ 15%, which is attained when dissolution exceeds a mass fraction loss of 10%.While the tip resistance decreases after dissolution, the drop in tip resistance is most pronounced in initially dense sands. A single penetration resistance versus density trend is observed for all tests, regardless of the changes in lateral stress and fabric that soils may have experienced as a result of mineral dissolution.