Numerical evaluation of liquefaction potential of heap of iron ore fines during maritime transportation

Several accidences related with the liquefaction problem of cargoes, such as iron ore fines (IOF), nickel ore, bauxite etc. during maritime transportation cause severe concerns of International Maritime Organization (IMO) and its members. The fact that some liquefiable cargoes were not specified clearly by the International Maritime Solid Bulk Cargoes (IMSBC) Code urges IMO to take action on making amendments for those cargoes. In this study, based on the results of a series laboratory tests on one type of iron ore fines, such as undrained monotonic loading and undrained cyclic triaxial tests considering both the saturated and unsaturated conditions, seepage analysis and dynamic response analysis on the IOF heap were conducted to reveal the water distribution in the heap for a given initial degree of saturation and to evaluate the liquefaction potential of the IOF heap. As the primary results, this study found a line indicting the possible maximum water level form in the IOF heap for a given initial degree of saturation. Though the used numerical models may need to be improved further, this study suggested a significant effect of liquefiable unsaturated IOF on the overall liquefaction potential of IOF heap.