STRUCTURAL OPTIMIZATION OF OFFSHORE JACKET PLATFORM

Abstract

Offshore structures support heavy loaded machineries like wind turbine, light house etc. Apart from dead loads and live loads, such structures are exposed to extreme environmental loads such as wave loads, wind loads etc. As a consequence, analysis and design of such structure is quite challenging to perform. This report presents the basic introduction of offshore structures, literature review, different techniques for optimization and finally results. The main objective of optimization is to minimize the weight of structure. Optimization of large scale structures like offshore structures, analysis of which are governed by complicated finite element analysis, are often computationally demanding. This often renders the use of conventional optimization techniques for such system computationally time consuming. To overcome it two new approaches have been proposed where Kriging is introduced and this technique is coupled with optimizing techniques i.e. Sequential Quadratic Programming (SQP) and Genetic Algorithms (GA). From numerical problem described in thesis it can be concluded that GA gives more reliable results than SQP. For optimizing offshore jacket platform GA coupled with Kriging technique has been used and the results have been presented in this report.