Ultimate Strength Analysis Of A FPSB Hull Girder And The Study Of Residual Ultimate Strength After Collision

As a new type of large floating offshore structure,Floating Process and Supply Base(FPSB)will suffer the rough sea in its life cycle,so it is very important to guarantee the safety of the structure in design.We can reduce the structure weight,lower the cost,and increase the deadweight as much as possible with the guide of the ultimate strength design method.This paper mainly research on the analysis method of the ultimate strength and the residual ultimate strength after damage of a FPSB hull girder.The main research work showed as following:1.The existing mainly research methods of the ultimate strength were expounded.The standard about the ultimate strength calculation and criterion of bulk carrier,oil tanker and offshore structure of IACS,ABS,BV,DNV societies were contrastive analyzed.2.The chosen of model length,mesh size,boundary condition etc.when use the nonlinear finite element method to calculate the FPSB hull girder ultimate strength were analyzed,and a method of built the simplified model of the FPSB hull girder was put forward.Then,the results of nonlinear finite element method were compared with the results of progressive collapse method.3.The residual ultimate strength of stiffened plates with dent-damage and initial distortion imperfections of a FPSB hull girder under uniaxial axial compression was studied.With the change of damage depth,damage length,damage width,and damage location this paper aimed to found the influence of those parameters through a series of calculation.Besides,a parameter sensitivity analysis was carried out.4.How the dent-damage and penetrating damage in the side or the bottom influenced the residual ultimate strength of the FPSB hull girder,and a relationship was found between the extent of damage and the residual ultimate strength index by a series of calculation.Besides,the influence of heel to the residual ultimate strength was also considered.