Researchonload Characteristic And Structural Response Of Ship's Cabin Fire

Steel is widely used in the manufacture of modern ships due to its varies excellent characteristics.But one of the most shortcoming of the steel is its poor resistance of fire and heat.Once ship is breaking out of fire,the structures of the ship will severely deform or even collapse.Base on this point,this paper devotes to studying the whole cabin's temperature field and structural responseof the structures of the ship's cabin which under the real fire.In the present stage of the fire simulation,ISO834 standard temperature rising curve is widely used in the research owing to its simple form of expression.Many scholars employ this curve to describe the temperature's tendency of the structures when they carry out the research on building fire and fire resistance of structures.Study on pool fire is conducted in this paper and find that the ISO834 standard temperature rising curve can not accurately describe the heating process of the real fire environment.So it is essential to redefine the temperature rising curve in the real fire's environment in order to realize the following fire-heat-structure's coupling analysis.FDS is used to simulate the temperature parameters of the fire in this paper.Then employ ABAQUS to analyze the mechanical properties to realize the coupling calculation.But the heat transfer hypothesis between these two softwares are different when calculating the temperature of solid.It is inaccurate to directly transfer the temperature from FDS to ABAQUS.In view of this point,boundary heat flux is employed as the coupling interface,mean time method is used to transmit data into ABAQUS so as to realize data butt to butt.Through to an example,the biggest error of the temperature is 5.90%.In this paper,sequential coupling is applied to carry out fire-heat-structure coupling analysis of cabin's deck and the whole cabin.Results find that the capacity of the structure declines nearly a half when the average temperature of the structure is 350?;When the average temperature reaches about 650?,the capacity of the structure decrease about 90%,almost has no bearing capacity.Due to the effect of fire,the temperature rising curve is different in different locations.The temperature gradient is emerged inside the structure.The larger the temperature and the temperature gradient,the larger the stress.Also the bigger the temperature,the bigger the strain.The construction process of the fire model in this paper is complex,on account of this,at the last of the paper,research is conducted based on the cabin's deck to simplified the model.The reduction of the material's modulus and the deck's thickness take the place of the heat load.The fire-heat-structure coupling analysis is simplified to the normal structural analysis to realize the model simplification.The simplified formula of fire model is concluded in a certain temperature range.