Study On The Optimization Of The Model And Design Parameter For 400ft Depth Jack-up Platform

The dissertation is supported by Defense Science and Engineering Office of ShanDong Province project named “Development of Jack-up Drilling Platform with Depth of 400 Feet”.Taking deepwater Jack-up unit as example,systematic study on the optimization of the model and design parameter for the SD-400 jack-up platform.The research covers some issues such as prediction model,dynamic response of sensibity,evaluation method and decision-making model of jack-up platform with depth in 400 feet,which acquires major progress and technological innovation.The research findings provide effective technical supports for the design of Jack-up drilling platform with 400 feet in depth.The main work is summarized as follows:(1)Study on prediction model of design parameters for 400 ft depth jack-up platformBased on the different design parameters of jack-up platform(water depth,drilling depth,main dimensions,variable loads,empty weight),we established design data base of jack-up platform.We formed prediction model of key parameters for 400 ft depth jack-up platform by using methods of mathematical statistics and artificial neural network..(2)Study on dynamic response of sensibility on deepwater jack-up platformTaking a deepwater Jack-up unit as research object,Parametric FEM of the unit for dynamic response analysis was established by using APDL language of ANSYS software.Based on that,the static analysis,modal analysis and transient dynamic analysis of the unit was performed,which determined the sensitivity of dynamic response of the unit to various parameters such as base,wave,unit,leg,etc.The influence of various parameters on the DAF of deepwater Jack-up unit was determined by the methods of displacement ratio and stress ratio,the results of which were compared with the results calculated by the method of single degree of freedom.The characteristics of dynamic response of the unit were obtained by above studies.(3)Study on evaluation method of design parameter adaptability for 400 ft depth jack-upWe developed a research on the design parameters based on the structure strength and buckling stability respectively with consideration of different design parameters,operation condition and exsiting requirement of norms and standards..(4)Study on design parameters decision-making model for 400 ft depth jack-upWe established a decision-making model for jack-up platform parameters optimization including desing parameters with which aimed optimization of adaptability under self storage condition.