Dense pile group deepwater bearing platform double-wall steel hanging box cofferdam construction process

The invention relates to the technical field of cofferdam construction, in particular to a dense pile group deepwater bearing platform double-wall steel hanging box cofferdam construction process. The dense pile group deepwater bearing platform double-wall steel hanging box cofferdam construction process comprises the following steps that A, construction preparation is carried out, specifically, a drilling pile steel casing is cut off, and a drilling platform is dismantled; B, a cofferdam bottom plate is assembled, specifically, bottom plate unit blocks are hoisted one by one by adopting a symmetry method, all the bottom plate unit blocks are assembled to form the bottom plate, and the steel casing penetrates through through holes in the bottom plate unit blocks, C, cofferdam side plates are assembled; D, cofferdam bottom sealing concrete is poured; and E, water is pumped, a cofferdam forth bearing system is converted, and a bearing platform is constructed, an anti-torque mechanism is arranged on each bottom