Engineering Quality Survey of Concrete Interlocking Soft Body Mattress Crossing under or over Optical Cable in Large Diameter Submarine Gas Pipeline Installation
Ma Ping (Shenneng(Group)Co.,Ltd.,Shanghai,201103,China) Liu Xiaojian(Shanghai LNG Co.,Ltd.,Shanghai,200021,China)
In submarine gas pipeline construction,pipeline- laying vessel is usually adopted to lay pipelines and conduct natural backfill after trench excavation soas tomake pipeline meet relative stabilityrequirements. Ifpipeline had to cross under or over optical cable,concrete interlocking soft body mattress shall be installed first to protect the existing optical cable. Survey of installation quality of concrete interlocking soft body mattress is a very important issue in marine construction project. Taking submarine pipeline construction in Shanghai LNG project as project case,systematically introduced are surveyprocess ofthe concrete interlocking soft body mattress by applying RTK- DGPS planar location and multi- beam side scan technology,listed are considerations and accurate survey results in the whole process,which provides valuable reference for future similar ocean engineering survey.