Box girder convenient to maintain

The utility model provides a box girder convenient to maintain. The box girder adopts a single-box three-chamber section; the bottom end of the middle of the box girder is fixed to the piers, two transverse partition plates are arranged on the inner side of the box girder and located at the joint of the piers, the transverse partition plates are arranged at intervals, and first manhole holes are formed in the transverse partition plates. The main span box girder is fixedly connected with the side span support box girder, an end partition plate is arranged at the outer end of the side span support box girder, and a second manhole is formed in the end partition plate. Maintenance supports are arranged in the box girder on the left and right sides of the diaphragm plate, supporting plates are fixedly connected to the top ends of the maintenance supports, and crawling ladders are arranged on the sides, close to the outer end of the box girder, of the maintenance supports and staggered with bottom channels of the