Large-span arched continuous rigid frame bridge Y-shaped pier construction system and construction method

The invention relates to a construction system and method for Y-shaped piers of a large-span arched continuous rigid frame bridge. The construction method comprises the following steps that the Y-shaped piers are constructed through a bearing platform upper supporting frame-built-in stiff framework-balance tower combined formwork system; constructing inclined legs section by section and then removing the mold; constructing a bearing platform and a construction platform in water by adopting an underwater platform auxiliary bracket span-reducing cable-stayed balance supporting system; and an inner side support self-balancing formwork pouring system is adopted. The method has the beneficial effects that the supporting frame-built-in stiff framework-balance tower combined formwork system on the bearing platform can achieve Y-shaped pier construction in a small construction site, meanwhile, the pier body line type and the construction quality can be guaranteed, and good reliability is achieved; according to the re