考虑群桩土体运移的浅海隔水导管变形分析  

Deformation analysis of conductor considering soil movement under pile group conditions in shallow sea

作　　者：霍宏博 刘询 刘铭 杨昕昊 孙大林 张春芳 HUO Hongbo;LIU Xun;LIU Ming;YANG Xinhao;SUN Dalin;ZHANG Chunfang(CNOOC China Limited,Tianjin Branch,Tianjin 300459,China)

机构地区：[1]中海石油(中国)有限公司天津分公司,天津300459

出　　处：《中国海上油气》2024年第4期181-189,共9页China Offshore Oil and Gas

摘　　要：浅海隔水导管作为海上油气田井筒的最外层结构,在海底硬土层中时常遭遇打桩受阻与管体变形问题,从而阻碍钻头通过,导致井槽浪费。结合渤海A区块海底土质,深入探讨了隔水导管锤入过程中的挤土效应、土塞效应、群桩效应以及往复锤击载荷的影响。通过有限元模拟,揭示了隔水导管群桩布局中土体的运移规律,明确了导管在拒锤后由于应力集中使得局部最大应力超出DH36钢的屈服强度,导致导管端部横向偏移以及缩径变形。基于研究结果,提出了针对性的优化方案,即通过优化隔水导管的壁厚尺寸来有效预防形变的发生。本项研究成果为特殊海底土质区域隔水导管的安全下入提供了有力支持,可为海上油气田的勘探与开发提供保障。The conductor in the shallow sea is the outermost shaft structure of offshore oil and gas fields,but the hard soil layer on the seabed often leads to pile driving obstruction and pipe deformation,preventing the drill bit from passing through and causing waste of well groove.By analyzing the seabed soil in Block A of the Bohai Sea,the influence of the soil squeezing effect,soil plug effect,pile group effect,and reciprocating hammer impact load during the hammering process of the conductor was discussed.Through finite element simulation,the soil movement law under the condition of pile group layout of the conductor was revealed.It was confirmed that the maximum local stress of the conductor exceeded the yield strength of DH36 steel due to stress concentration after the hammer rejection,which led to transverse deviation and necking deformation of the conductor end.Based on the research results,a specific optimization scheme was proposed to prevent the deformation effectively by optimizing the wall thickness of the conductor.The research results provide strong support for the safe running of the conductor in special seabed soil areas and for the exploration and development of offshore oil and gas fields.

关 键 词：隔水导管 锤入法 打桩 应力集中 

分 类 号：TE951[石油与天然气工程—石油机械设备]