海底管道穿越航道段不停输下卧技术

针对某项目海底管道与航道交叉段的埋深要求，分析对比常用的输送介质停输状态旁侧新建管道下卧及输送介质不停输管道原地下卧两种方法。结合附近海域已建管缆现状、航道区域水深、海床底质、管道参数等条件，对下卧及在位期应力及下卧期抗上浮稳定性进行分析评估，推荐采用海底管道不停输后挖沟下卧方案。结合后挖沟设备的下卧能力，综合考虑采用分步实施、分层开挖的方式对在役管道进行下卧，并对下卧施工关键参数进行分析，给出具体实施措施，为后续项目提供借鉴。

Lowering Technology of Live Subsea Pipeline on Crossing Channel Section

According to the buried depth requirements of the crossing channel section of the subsea pipeline, the commonly used lowering methods are analyzed and compared, including newly built pipeline nearby and lowering the live pipeline. Taken the current situation of the pipelines and cables built in the nearby sea area, the water depth of the shipping channel, the seabed bottom soil and the pipeline parameters into consideration, the lowering and in-place stresses and the anti-floating evaluation are assessed. It is recommended to lower the live subsea pipeline by post-trench technology. Combining the ability of the post-trench equipment, adopting step-by-step implementation and layered excavation to lay down the live pipelines is comprehensively considered. The key parameters of the lowering construction are analyzed, and the specific implementation measures are given to provide reference for the implementation of the subsequent projects.