中文摘要：

对于载运重大件的半潜船,多数权威机构只规定了初稳性高（GM）的最小限值,但未对GM最高限值做出规定.GM过大时,船舶横摇周期就会变短,船舶在风浪中会产生剧烈摇荡.为保障运输安全,从提供足够的复原力及避免谐摇这两个角度出发,推导出半潜船稳性高可行域计算公式.在装载某一特定重大件前,利用该公式初步判断半潜船装载该重大件时初稳性高是否满足要求.以一艘半潜船运载自升式钻井平台为例,利用该计算公式对其稳性进行了分析,同时根据该公式提出提高船舶航行稳性的方法.

英文摘要：

For semi-submersible vessels carrying special heavy cargo,most authorities only provides a minimum limit of GM,without a provision for the maximum limit of GM.However,when GMis too high,the rolling period of the vessel will become shorter,which will cause severe shaking.From the aspects of providing sufficient righting arm and avoiding harmonic shake,this paper deduces a formula to calculate the feasible range of GM to maintain the stability of the semi-submersible vessel.Before the semi-submersible vessel loading a specific special heavy cargo,this formula can be used to preliminary judge whether the GM of this vessel meeting the requirement to load this cargo.Finally,a semisubmersible vessel carrying ajack up drilling platform is taken an example,by using this calculation formula,the stability of the semi-submersible vessel is analyzed and some methods improving sailing stability have been put forward.