后挖沟深度对深海海底管道屈曲影响数值分析  

Numerical analysis of the influence of post-trench depth on buckling of deep sea submarine pipeline

作　　者：李修波 刘可安 王华昆[3] 王鸿飞 LI Xiubo;LIU Kean;WANG Huakun;WANG Hongfei(CRRC SMD (Shanghai) Ltd., Shanghai 200240, China;Zhuzhou RRC Times Electric Co., Ltd., Zhuzhou 412001, China;State Kay Laboratory of Hydraulic Engineering Simulation and Safety, School of Civil Engineering, Tianjin University, Tianjin 300072, China)

机构地区：[1]上海中车艾森迪海洋装备有限公司,上海200240 [2]株洲中车时代电气股份有限公司,湖南株洲412001 [3]天津大学水利工程仿真与安全国家重点实验室,天津300072

出　　处：《海洋工程》2020年第3期152-160,共9页The Ocean Engineering

基　　金：国家重点研发计划(2016YFC0304104)。

摘　　要：鉴于海底管道的服役水深越来越深,主要采用犁式挖沟机对预铺设于海床之上的海底管道采取后挖沟的方式将海底管道埋设于海床之下,以保护其免受不必要的损伤。针对后挖沟深度H是海底挖沟机的重要设计参数,也是影响管道悬跨的重要因素的问题,对SMD(UK)犁式挖沟机展开参数优化,确保作业过程中悬跨段管道在外部静水压力作用下,海底管道不会发生屈曲破坏。采用ABAQUS软件,分别建立了作业前和作业中两种工况下的悬跨模型,分析机械手对接触部分管道的损伤,结果显示,作业中的机械手对悬跨管道的损伤更大;同时,建立了作业中不同管径下,后挖沟深度对管道损伤的安全裕量关系曲线。进一步,结合作业中不同挖沟深度下的管跨段屈曲数值模型,对处于外部静水压力作用下的悬跨管的屈曲失效展开分析,结果显示,随着后挖沟深度的加大,不同管径下的悬跨段管道局部出现塑性压溃的临界压力值不断降低;管道外径的增大,降低了同一后挖沟深度下发生屈曲失效的压力值。最后,在后挖沟深度与外部静水压力组成的区域内,建立屈曲失效临界关系曲线,并划分出工作区和压溃区,为深海管道后挖沟埋管的施工提供工程参考。In view of the deepening of the service depth of the submarine pipeline,the submarine pipeline pre-layed on the seabed is mainly buried under the seabed by means of a plough trencher with post-trenching to protect it from unnecessary damage.Aiming at the problem that the post-trench depth H is an important design parameter of the subsea trencher and an important factor affecting the pipeline span,the parameters of the SMD(UK)subsea plough is optimized to ensure that the suspension submarine pipeline under the external hydrostatic pressure during operation will not undergo buckling failure.In this paper,the ABAQUS software is used to establish the suspension model under the two working conditions before and during the operation,and the damage of the manipulator to the part of the pipeline is analyzed.The results show that the manipulator makes more damage to the suspended pipeline during operation.A safety margin curve for the damage of the pipe with different pipe diameters and the depth of the trench are established.Furthermore,a numerical model of the pipe suspended buckling under different trench depths is established,and the buckling failure of the suspension pipe under external hydrostatic pressure is analyzed.The results show that as the depth of the post-trench increases,the critical pressure value of the buckling of the suspended section pipe with different pipeline diameters is continuously reduced;the increase of the outer diameter of the pipe reduces the pressure value of buckling failure under the same post-trench depth.Finally,in the area composed of the post-trench depth and the external hydrostatic pressure,a critical relationship curve is established,and the working area and the buckling area are divided to provide engineering reference for the construction of the post-trench.

关 键 词：犁式挖沟机 后挖沟深度 海底管道 屈曲失效 损伤模型 压溃压力 

分 类 号：TE832[石油与天然气工程—油气储运工程]