A comparison between periodic and fixed BC for structural analysis of flexible risers

In this project, the mechanical behaviour of a single CFT as a column subjected to axial compression will be analysed by finite element method. Both linear and nonlinear material properties of steel and concrete will be considered and the numerical results will be compared with a set of test results conducted by Harbin Institute of Technology, China. Then some interface defects between the steel and the filled concrete will be introduced to investigate their effects on the overall behaviour of the CFT and also the possible local buckling of the steel tube which has been observed in tests and in real structures. At the next stage, a few commonly used CFT joint sections will be modelled under both static and dynamic loading conditions, and their performance will be compared in terms of the maximum stresses and their locations identified. Finally, based on these simulations, some optimised designs of CFT joints will be proposed.