Tunnel arch bottom desilting device

The utility model discloses a tunnel arch bottom desilting device, and relates to the technical field of hydraulic engineering desilting, the tunnel arch bottom desilting device comprises a desilting device main body, a supporting column, a transport vehicle and a collecting box, the interior of the desilting device main body is fixedly provided with a rotating column, and the top end of the rotating column is fixedly provided with a power motor; supporting columns are arranged at the bottom of the dredging device body. The movable block and the movable rod are matched with each other, so that the movable block drives the movable rod to move on the sliding rail, then the movable rod drives the scraping plate to move while moving, the friction pad and the friction block are matched with each other, the scraping plate conveniently scrapes blocked sludge, and then the scraping plate is matched with the friction pad to push the sludge to move; and the problem that when the desilting device conveys sludge, the slu