Spraying maintenance device for prefabricated box girder and spraying maintenance method thereof

The invention provides a prefabricated box girder spraying maintenance device and a spraying maintenance method thereof. The prefabricated box girder spraying maintenance device comprises a supporting part, a walking part, a first spraying maintenance part, a second spraying maintenance part, a water storage part and a maintenance water collecting part. Wherein the second spraying maintenance part comprises a first spraying piece and a second spraying piece, and the angle of an included angle formed between the first spraying piece and the second spraying piece can be adjusted. The first sliding groove is formed in the spraying installation part of the second spraying maintenance part, so that the sliding part can slide in a reciprocating mode in the extending direction of the first sliding groove, and reciprocating sliding of the sliding part can be converted into reciprocating swinging of the first spraying part and the second spraying part through the transmission assembly; therefore, full spraying mainten