Optimum Design For Tension Leg Platform

With better performance than Semi and Spar,tension leg platform will be the preferred unit for South Chine Sea oil exploitation.This theisi is in order to solve encountered problems in structure design process of tension leg platform.The main content is as follows.The author firstly does the strcucture design,including structure classification and material selection,global and detail sizing,with a global structure FEM model completed.Then proper wave loads analysis theory and wave theory are chosen according to the platform structure and size feature.Based on the theories,hydrodynamic analysis considering the effect of tendon pretension is completed.The hydrodynamic responses with different column diameters,pretensions,tendon angles and numbers are analyzed and compared,in order to acquire the optimum size of the platform.Several kinds of design wave method are applied to the tension leg platform considering the effect of tendon,some of which are modified based on result anaysis.In this process,wave steepness of South China Sea is obtained.Also a new method for the tension leg platform in the particular deep sea area of South China Sea is proposed.Two kinds of operation condition and 15 characteristic loads are selected to perform the conditons combination.A new strength evaluation method is proposed and adopted to analyze and check global strength.Also an optimum design is performed based on the result analysis.The analysis in this thesis provides proper approach for those key practices in related rules and regulations,gives suggestion for the selection of design wave parameters calculation method of tension leg platform,proposes a new method to evaluate the global structure strength.