The Elastic-plastic Analysis Of Offshore Platform With Double Rocking Columns Subjected To Ice Loads And Seismic Loads

It is very important to study the mechanical property of offshore platform in the extreme condition.Because the offshore platform's structure is complicate and the ocean environment is multivariable.It is purpose to meet the offshore platform's safety requirements under the extreme load control,this paper main combines the research status of offshore platform about elastic-plastic analysis.The main contents are as follows:Firstly,for the structure of JZ20-2 offshore platform,it combines the research status at home and abroad of the elastic-plastic analysis' s achievement.It is based on the analysis of JZ20-2 offshore platform under the control of the extreme ice load and seismic load,the destroyed rules of offshore platform has been defined.It summarizes the failure criterion of the offshore platform.We can use the structure of the plastic stress failure criterion and the structure deformation criteria to determine.Secondly,for the new offshore platform with rocking column structural system,it propose the offshore platform with two rocking columns structural system.It main studys the size of the link rod,the size of the rocking column and the link rod connections.At the same time,the original offshore platform and the platform with rocking column have been analyzed to find the effect of rocking column.Thirdly,for the offshore platform with two rocking columns structural system and the other two structural system,it runs harmonic response analysis,modal analysis and low cycle reciprocating analysis.At the same time,it runs the push-over analysis about simulation of static ice force.Fourthly,for the offshore platform with two rocking columns structural system and the other two structural system under the control of extreme ice load,the results use to analyze their structural response in the plastic state.It indicates that the offshore platform with two rocking columns structural system has the better structural and mechanical property.Fifthly,for the offshore platform withtwo rocking columns structural system and the other two structural system under the control of extreme seismic load,the results use to analyze their structural response in the plastic state.It indicates that the offshore platform with two rocking columns structural system has the better structural and mechanical property.The method of IDA can be used to determine the limits of structure deformation and the ultimate bearing capacity.