A Study On The Liquefying Mechanism Of Cargoes Which May Liquefy

There has been a number of the sinking due to liquefaction of bulk cargoes in recent years. International dry bulk ship owners association (INTERCARGO) have repeatedly warned the risk of liquefaction, and strengthen the testing and verification of the transport conditions of iron ore powder and nickel ore by IMO. However, when the moisture content of mineral powder and other solid bulk cargoes below the TML, ship may also heel seriously, even capsize due to liquefaction of cargoes; when the moisture content of mineral powder and other solid bulk cargoes above the TML, ship may also arrive the destination safely. Therefore, it is necessary to identify the basic concepts of liquefaction of bulk cargoes, in-depth study of the liquefaction mechanism of cargoes, and provide theoretical guidance for transportation.This paper expounds the liquefaction mechanism of the cargoes which may liquefy from the perspective of Soil mechanics. By studying the reasons and the definition of soil liquefaction, the second chapter gives the reasons and the definition of liquefaction of cargoes which may liquefy, and analyzes the influence factors such as soil particle size effects on soil liquefaction. In addition, through studying the relationship between the water content and the shear strength of soil, using the changing rule of the soil shear strength curve with water content, reclassify the mineral powders in the IMSBC rules.The third chapter analyzes the liquefaction degree of the cargoes which may liquefy, puts forward the concept of degree of liquefaction, and establishes the function relation between the angle of repose of liquefied cargo and liquefaction degree. In addition, the third chapter also studies and defines the liquefaction velocity of the cargo, and expounds the influence of the liquefaction velocity to ship. Finally, analyzation is made on actual cases to prove the liquefaction mechanism and proposed definitions.The study contents and conclusions of this paper provides a beneficial reference for shipping of cargoes which may liquefy, offers a practical and effective guidance to cargoes such as mineral powders, reduces the risk of transportation of liquefying cargo by sea, and ensures safety of personnel, cargoes, and the marine environment.