Construction and waterproofing method for top plate cofferdam of comprehensive pipe gallery in river-crossing section

The invention relates to a river-crossing section comprehensive pipe gallery roof cofferdam construction and waterproof method. The method comprises the following steps that before first-stage pipe gallery construction, a river blocking cofferdam and a river-following cofferdam are constructed at first; after construction of the first-stage pipe gallery is completed and before backfilling, a pine cofferdam is constructed on a top plate of the first-stage pipe gallery; waterproof coiled material waterproof construction is conducted on the pine cofferdam; first-stage backfilling is conducted, and a second-stage cofferdam is constructed. According to the river-crossing section comprehensive pipe gallery roof cofferdam construction and waterproof method, the pine cofferdam is constructed after the first-stage pipe gallery construction is completed and before backfilling is conducted, and the problems that in a conventional construction process, the driving perpendicularity of pine piles is not well controlled, or