中文摘要：

半潜式平台垂荡响应较大,对生产平台立管和采油树系统的选择、钻井平台钻杆升沉补偿装置等提出更高要求,增大了作业和维护成本。针对这一问题,在传统结构基础上提出了三种新的结构概念：1）在浮筒底部加垂荡板;2）沿立柱外延加垂荡板;3）改变立柱为变截面结构。通过数值分析对各平台模型水动力性能进行比较,结果表明,各新型结构对半潜式平台垂荡起到一定程度的抑制效果。由于在浮筒底部加垂荡板的方案效果比较突出,对该方案进一步做了优化和改进工作,并对平台在南海百年一遇波浪环境条件下的垂荡响应概率密度函数和响应极值进行了预报和对比研究。

英文摘要：

As the water depth gets deeper,semi-submersible platforms are facing a growing number of challenges,especially the large heave response. In order to improve the performance of the semi,three new structural concepts are proposed based on the traditional semi structure. Hydrodynamic analysis is done by conducting numerical computation,and the results denote that all the new concepts are beneficial to control heave motion and some have significant effects. Of the three new concepts,the first one has the best performance. The further optimization is conducted,and the probability density function and the extreme values of the semi＇s heave response under wave station with 100-year return period are forecasted.