Waterproof and anti-garbage cover plate device for inner cavity of tubular pile

The waterproof and anti-garbage cover plate device comprises a cover plate, the middle of the cover plate is sleeved with a screw capable of moving up and down, a supporting device is arranged below the cover plate and comprises supporting legs and expansion connecting rods, the tops of the supporting legs are rotationally connected with the bottom of the cover plate, and the bottoms of the supporting legs face the inner wall of the tubular pile; the upper end of the expansion connecting rod is sleeved with the screw rod, the lower end of the expansion connecting rod is in screwed connection with the screw rod, and the middle of the expansion connecting rod is rotationally connected with the side, away from the pipe pile, of the lower end of the supporting leg. Rainwater, silt and the like can be effectively prevented from flowing into the pipeline cavity, the defect that time and labor are wasted when the pipe pile cavity is cleaned in the later period is overcome, meanwhile, the expansion connecting rods ar