Variation of the geotechnical properties of Iron Ore Fines under cyclic loading

Liquefaction, which can result in a vessel capsizing, is one of many hazards involved when transporting bulk cargoes. The objective of this study is to determine the variability of the geotechnical properties of Iron Ore Fines (IOF) under cyclic loading at different moisture contents to determine the liquefaction potential. The geotechnical properties include the void ratio, dry density, degree of saturation and angle of repose. Previous studies have proven that in a partially saturated material, under cyclic loading, these properties directly effect the shear strength and may cause a material to liquefy. Also, by measuring the penetration of a free floating IOF Plunger (IOFP), developed during this study, the loss of shear strength was monitored. The results from this study show that significant variations occur in the geotechnical properties of IOF under cyclic loading at the varying moisture contents tested. Penetration from the IOFP was also observed, which indicated a reduction of effective stress and therefore shear strength within the samples IOF. The samples tested showed signs of liquefaction between the Proctor/Fagerberg and Modified Proctor/Fagerberg transportable moisture limits. It was concluded that the liquefaction potential of IOF is a function of the time of cyclic loading and initial moisture content.