Underwater Open-cut Crossing Technology to Cross Dawen River of Ji'ning Gas Transmission Pipeline

The technical program demonstrations on Ji'ning Gas Transmission Pipeline to cross Dawen River are made, and a demonstrated result, a design program is determined, that is, underwater open-cut, car launching, negative buoyancy controlling, dragging pipe underwater based on the hydrologic data the River. Dawen River is an ephemeral stream with a flow rate of 160-210 m³/sec surveyed in June in Tai'an, Shandong Province. The analysis conclusion displays that this crossing program is characterized by lower risk and feasibility. The crossing construction program of pipeline is successfully put into operation, which provides the technology support for pipeline construction in the same environment.