Composite waterproof pile casing for reserved hole

The invention discloses a composite waterproof pile casing for a reserved hole, and relates to the field of building waterproof structures. The composite waterproof pile casing for the reserved hole comprises an underneath pass pipeline, a water-swelling water stop sleeve arranged on the underneath pass pipeline in a sleeving mode and a waterproof sleeve arranged on the water-swelling water stop sleeve in a sleeving mode, and the two ends of the water-swelling water stop sleeve stretch out and are overturned to wrap the outer walls of the two ends of the waterproof sleeve correspondingly. The outer walls of the two ends of the waterproof sleeve are connected with a grouting pipe and an exhaust pipe communicating with the inner walls of the waterproof sleeve correspondingly. According to the composite waterproof pile casing for the reserved hole, the corrosion of the embedded steel bars caused by water erosion of a wall body due to the dual effects of the reserved hole and underground water can be effectively