Abstract
Semi-submersibles, best-suitable for oil and gas exploration in ultra-deep waters, possess attractive stability characteristics. While well-defined installation practices also bound them, failure of mooring lines shall pose challenges to their functional safety. Postulated failure analyses of a semi-submersible in 1500 m water depth in the Gulf of Mexico, installed with two other moorings namely: spread catenary and taut-moored, are discussed, and the fatigue damage is estimated using S–N curve approach. Results showed that while the motion responses of the semi-submersible with the proposed spread mooring are within the permissible limits, the fatigue life of the remaining mooring under the postulated failure condition is significantly decreased. Results show that the motion responses of semi-submersible with the proposed spread mooring are found to be within the permissible limits, except for a marginal increase under the mooring failure case. Tension in the remaining mooring lines is found to be dependent on the position of the failed mooring lines.
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Chandrasekaran, S., Uddin, S.A. Postulated failure analyses of a spread-moored semi-submersible. Innov. Infrastruct. Solut. 5, 36 (2020). https://doi.org/10.1007/s41062-020-0284-2
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DOI: https://doi.org/10.1007/s41062-020-0284-2