Analyze And Research On Multi-component Mooring System

Sea contains giant oil and gas resources, facing the land resources is deficient day after day, the exploitation and usage of sea resources are receiving more and more attention. Marine structures become more and more, operated in deep water areas, as the development of ocean engineering proceeds. They should anchor in deep water often in long time, which are requested higher anchoring performance comparing with the ordinary ships. Currently, submerged oil drilling platform and the floating production and storage offloading system are already becomes the main tool of the ocean exploitation. In order to guarantee the platform and other floating things working under the majority sea condition, the design of the mooring system of sea structure is especially important.Mooring system for floating platform usually takes multiple segments combination in deep water such as wire rope and chain combinations related to many parameters. Multi-component mooring lines compose mooring systems used in deep water, while versatile parameters bring difficulties to design work. This paper deduces catenaries equations of multi-component mooring lines according to the Quasi-Static method in a specific water depth. It also compiles calculative process of muti-component mooring system and builds a minimum model for choosing optimal parameters of multi-component the mooring lines, and illustrating the weight and technical factors. Inspired by the work of predecessors, make full use of the centenary's equation ,to know how the parameters change about water depth, horizontal force and stretching force of catenary.ect.In order to solve the optimization problem, optimization tool and Genetic Algorithm tool are employed. It has also been applied to practical design assignment, and this paper analyzes and compared with the two results and draws relevant conclusions. Through the analysis of the paper, the author have an initial understanding of the combinatorial optimization problems of the multi-components mooring lines. The conclusion shows, If the design is reasonable, restoring force of multi-component mooring lines system usually greater than that of all wire rope (or all chain) system. The methods and the conclusions of this paper have some reference value and engineering practical directive significance to study and the preliminary design of the multi-component mooring lines in mooring system. The dissertation is endeavor to make this work further, and it is hopefully to applied for other similar kind of deep water mooring design in the future.