China Ocean Engineering

, Volume 32, Issue 6, pp 683–695 | Cite as

Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States

  • Lin-jian Wu
  • Yuan-zhan Wang
  • Yu-chi WangEmail author
  • Jia-yu Chen
  • Yi Li
  • Qing-mei Li
  • Tao Xie


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.

Key words

mobile offshore base (MOB) flexible connectors the optimal stiffness rough sea states 


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Copyright information

© Chinese Ocean Engineering Society and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Lin-jian Wu
    • 1
  • Yuan-zhan Wang
    • 1
  • Yu-chi Wang
    • 2
    • 3
    Email author
  • Jia-yu Chen
    • 4
  • Yi Li
    • 5
  • Qing-mei Li
    • 1
  • Tao Xie
    • 1
  1. 1.State Key Laboratory of Hydraulic Engineering Simulation and Safety, Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationTianjin UniversityTianjinChina
  2. 2.School of Civil EngineeringTianjin UniversityTianjinChina
  3. 3.College of EngineeringOcean University of ChinaQingdaoChina
  4. 4.Chongqing Shipping Engineering Survey and Design Institute of the Yangtze RiverChongqingChina
  5. 5.School of River & Ocean EngineeringChongqing Jiaotong UniversityChongqingChina

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