Method for plugging diversion tunnel by cast-in-situ reinforced concrete without cutoff by gate and plugging reinforcing cage

The invention discloses a method for plugging a diversion tunnel by cast-in-situ reinforced concrete without cutoff by a gate and a plugging reinforcing cage. The method for plugging the diversion tunnel by the case-in-situ reinforced concrete without cutoff by the gate and the plugging reinforcing cage have the advantages that the process of closing the gate for the diversion tunnel can be removed, the project amount of gate concrete is reduced, and meanwhile concrete plugging can be conducted in the process that normal stream diversion is achieved in the diversion tunnel. The plugging reinforcing cage is fixedly provided with a plurality of drain pipes, after a plurality of plugging reinforcing cages are assembled and combined, a cross sectional area is just the cross sectional area of the diversion tunnel, the plugging reinforcing cages are sequentially placed inside the diversion tunnel, or the diversion tunnel is divided into a plurality of areas to be respectively provided with mesh reinforcing frames with drain pipes in an erecting mode, concrete is sequentially poured, when the concrete strength reaches a design requirement, a gate of the drain pipes is closed, normal pouring is conducted to plug concrete on the back face of the gate, and the gate is poured in the concrete.