Dry dock arrangement method based on immersed tunnel crossing river

The invention provides a dry dock arrangement method based on an immersed tunnel crossing a centerline, which comprises the following steps of: taking a foundation trench excavated in the middle line of a tunnel line on the upper edge of the centerline as a dry dock prefabricated pipe joint, dragging a first batch of pipe joints out of the dock through dock gate hinges arranged at two ends of the foundation trench to carry out sinking butt joint, and prefabricating subsequent batches of pipe joints after a dock gate is recovered; and the last batch of pipe joints are foundation trench inner pipe joints, sinking butt joint is carried out through ground anchor hinge dragging, final joints are poured in an underwater joint mode, and finally construction of the immersed tunnel is completed. According to the method, a dry dock does not need to be independently built, the problem that the site selection difficulty of a different-place dry dock is large is solved, long-distance floating transportation is not needed,