Reinforcing device for large-section concrete beam and construction method

The reinforcing device comprises a left steel back ridge, a right steel back ridge, a plurality of split bolts and fixing bolts, the left steel back ridge and the right steel back ridge are symmetrically arranged, and a plurality of bolt holes are symmetrically formed in the left steel back ridge and the right steel back ridge; the fixing bolts and the split bolts are connected to the left steel back ridge and the right steel back ridge through the bolt holes to form a U-shaped component reinforcing device, the concrete beam formwork is rapidly reinforced and disassembled, the problem that in a traditional method, the construction process is complex is solved, the construction efficiency is greatly improved, and the labor cost is effectively reduced. The overall reinforcing rigidity is improved, the phenomena of mold expansion, mold shifting and slurry leakage are greatly reduced, the structure forming quality is improved, and the forming quality is stable. And the steel pipes can be repeatedly used for multi