Structural risk analysis of an NO96 membrane-type liquified natural gas carrier in Baltic ice operation

Abstract

The present study considers the results of a structural risk analysis for a 170 000 m³ vessel with Ice Class IA classification operating from the Baltic Sea to Quebec, Canada. The target vessel is characterized by a Gaz Transport/Technigas (GTT) NO96 containment system for liquified natural gas (LNG) cargo. The capacity of the double-hull structure has been assessed considering inner hull deflection as the critical factor for the safety of the containment system. This capacity is compared with accidental ice load, termed as ‘demand’ to the LNG carrier, from ice hazards that can occur during Baltic Sea operation in winter or while operating on the Canadian east coast. Risk analysis has been performed to evaluate the risks of the considered ice features in the operation route, based on the study of capacity and demand.

Keywords

risk analysis ice hazard GTT NO96 liquefied natural gas carrier Ice Class IA ice collision

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