Abstract
This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base (MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures.
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Foundation item: This work was financially supported by the National Key Research and Development Program of China (Grant Nos. 2016YFC0802204 and 2016YFC0802201), the National Natural Science Foundation of China (Grant No. 51679166), the National Natural Science Fund for Innovative Research Groups Science Foundation (Grant No. 51321065), the Construction Science and Technology Project of the Ministry of Transport of the People’s Republic of China (Grant No. 2014328224040), and the Innovative Research Program for Graduate Students at Chongqing Jiaotong University (Grant No. 20140104).
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Wu, Lj., Wang, Yz., Wang, Yc. et al. Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States. China Ocean Eng 32, 683–695 (2018). https://doi.org/10.1007/s13344-018-0070-5
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DOI: https://doi.org/10.1007/s13344-018-0070-5