摘要
在深水海域铺设海底管道的环境条件往往比浅水区域更加恶劣,将会在管道垂弯区产生较大的荷载组合,可能导致管道发生屈曲破坏.为确保管道的安全,将深水海底管道简化为理想弹塑性材料,对管道铺设时的受力状态进行理论分析.以最大变形能密度为屈服准则,推导出海底管道在弯矩、轴向拉力和外压共同作用下的极限承载能力公式,并应用到S型深水铺管施工受力分析中.结果表明,水深越深则管道上的荷载组合越大,径厚比越大则管道的极限承载能力越小.使用推导出的深水管道极限承载能力公式可以快速、有效地判别管道是否安全.当铺设水深超过3500m时,算例中径厚比为20的管道将发生屈曲破坏,而在2000m水深时,径厚比超过30的管道才会发生屈曲破坏.
The submarine pipelines in deepwater sea area are subjected to more severe environmental loads than those in shallow water during the installation process,therefore the load combination could become critical and the local buckling may occur in the sagbend segment of pipelines.For ensuring pipeline safety,theoretical analysis for mechanical characteristics of deepwater submarine pipes was carried out with the assumption that the stress versus strain curve of the pipe material is elastic-perfectly plastic.The ultimate bearing capacity of pipes under the combined bending,longitudinal tension force and external hydro-static pressure was derived according to the maximum deformation energy density yield criterion.Then the formula of ultimate bearing capacity was applied to S-Lay technique to evaluate the safety of pipes.The results show that the load combination acting on the pipes increases as the water depth increases,and the ultimate bearing capacity of pipes decreases as the ratio of diameter to thickness increases.It is very convenient and effective to evaluate the safety of pipes with the derived equation.When the pipe-laying depth is larger than 3 500 m,the pipe with the ratio of diameter to thickness of 20 in the example may occur buckling failure,and the pipeline will be failure with the ratio of diameter to thickness greater than 30 for 2 000 m water depth.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2010年第4期778-782,共5页
Journal of Zhejiang University：Engineering Science
基金
国家"863"高技术研究发展计划资助项目(2006AA09A105)
关键词
海底管道
管道铺设
荷载组合
极限承载能力
submarine pipe
pipe-laying
load combination
ultimate bearing capacity
