期刊名称：Majalah Iptek = IPTEK : The Journal for Technology and Science
印刷版ISSN：0853-4098
电子版ISSN：2088-2033
出版年度：2019
卷号：30
期号：1
页码：19-23
DOI：10.12962/j20882033.v30i1.5009
出版社：IPTEK
摘要：This paper studies fatigue life of mooring lines applied on turret-moored Floating LNG (Liquefied Natural
Gas). Several case studies were designed to investigate the influence of mooring pretension and water depth on the fatigue
life of mooring lines. Floating LNG with permanent external turret mooring system consists of 12 catenary lines arranged in
3 groups with four lines each. Time domain simulation applied to calculated coupled dynamic response and mooring
tension. Fatigue life is assessed using the rain-flow counting method, T-N curves, and Palmgren-Miner rule. Analysis results
for mooring pretension case show that case study 2 with the lowest pretension (14%MBL) yields shortest mooring fatigue
life of 1814.20 years compared to case study 1 (18%MBL) and 3 (22%MBL) with 2034.61 years and 2983.33 years
respectively. Despite having the lowest dynamic line tension, case study 2 has a larger tension range that results in the
increased of fatigue damage. The increase in water depth will increase the mooring line length and its weight, so it results in
an increase in fatigue damage. It is reflected in case study 5 (903m water depth), which has shortest mooring fatigue life of
1842.65 years compare to case study 1 (602m water depth) and 4 (301m water depth) with 2983.33 years and 3363.62 years
respectively.
