自升式平台就位过程触底分析  

Grounding Analysis of the Jack-up Unit during Positioning Process

作　　者：许海东[1] 隋依 XU Hai-dong;SUI Yi(CNOOC Energy Technology & Services Oil Production Services Company, Tianjin 300452, China;College Of Engineering, Ocean University of China, Qingdao Shandong 266100, China)

机构地区：[1]中海油能源发展股份有限公司采油服务分公司,天津300452 [2]中国海洋大学工程学院,山东青岛266100

出　　处：《船海工程》2021年第3期4-9,共6页Ship & Ocean Engineering

基　　金：工信部高技术船舶科研项目(工信部装函[2014]506号);广西重点研发计划项目(桂科AB20159012)。

摘　　要：针对自升式平台就位下放桩腿至海底时,桩靴与海底可能发生触底碰撞,造成桩腿、桩靴等结构损坏,影响平台安全的问题,为防止桩靴与海底的撞击力过大,通常限制作业环境条件。以某平台为例,基于三维势流理论和莫里森方程,采用频域方法研究就位过程中桩腿下放至接近海床时平台的水动力响应,考虑3种不同海况,以RAO分析结果为基础,参照模拟靶谱法与刚体运动特性完成频-时域转换,获得桩靴底部垂向速度的最大值。基于显式动力分析方法,建立桩腿-桩靴-地基的有限元模型,选取3种海洋地基,以垂向速度最大值为数值模拟的动力因素,对碰撞过程进行仿真模拟,分析碰撞过程中结构应力变化并给出平台安全就位的海况信息,为就位过程触底碰撞提供计算和评估模式。The spudcan may ground when the leg of jack-up unit is lowered to the seabed during positioning process,resulting in structural damage of the leg and spudcan to affect the safety.The operating environment conditions are usually limited to reduce the impact force between spudcan and seabed.Taking a jack-up unit as the research object,based on three-dimensional potential flow theory and Morrison equation,the frequency-domain method was used to calculate the hydrodynamic response when the legs close to the seabed during positioning process.Considering three different sea conditions,based on hydrodynamic results such as RAO,the maximum vertical velocity of the bottom of spudcan was determined in different sea condition according to target method and rigid-body motion characteristics.Based on explicit dynamic analysis method,leg-spudcan-seabed model was established with three selected marine foundation condition to simulate the grounding process,analyzing the stress change and assessing the structural strength,so as to determine the safe sea state of the jack-up unit.It provides a calculation method and assessment mode for grounding during positioning process.

关 键 词：自升式平台 就位 显示动力分析 触底碰撞 

分 类 号：U674.38[交通运输工程—船舶及航道工程]