Research On Deformation Mechanism Of Jacket Platform Circular Tubes Under Lateral Impact

Jackets platforms supported with circular tubes have been widely applied. It is important to keep the platforms operating safely. Structural damage will threaten staff security, and may lead to economic lose and environment pollution. Generally, the circular tubes may be struck by the shipside of a supply vessel when it approaches the platform. The deformation mechanism and energy dissipation of the tubes is the key point for research of the inclined tubes.Two methods are used in this paper, simplified analytical method and numerical simulation. The simplified analytical method is suitable for rapid prediction. Based on non-linear finite element method, the numerical simulation may give the results of many physical quantities during the indentation process, and become verifications of the results of simplified analytical method. The main work includes: 1. A review of research methods of ship collision internal mechanism. It is introduces in this paper the theoretical basis and stages of simplified analytical method. Moreover, the previous researches on deformation property of circular tubes under loading are involved. 2. By the analysis of former researches, the deficiency is modified. The deformation mechanism of ends-fixed circular tubes under lateral impact is provided. Then simplified analytical formula is derived by the use of simplified analytical method. 3. With the application of NLFEM, deformation of inclined circular tubes under lateral impact is simulated numerically. The results are compared with that of simplified method.The simplified analytical methods and results calculated in this paper can contribute to rapid and reliable assessment of inclined circular tubes under lateral surface loading. And it is meaningful for the crashworthiness design in preliminary design stage.