Pile bottom sediment sampler

The utility model belongs to the technical field of cast-in-place pile sediment collection, and discloses a pile bottom sediment collector which comprises a sediment collection pipe and an air seal assembly. Specifically, the air seal assembly comprises a bearing part and a sealing part, the bearing part comprises a connecting part, a bearing part and an air guide pipe which are sequentially connected from bottom to top, the connecting part is connected with the slag collecting pipe, a hole channel is formed in the bearing part, one end of the hole channel communicates with the slag collecting pipe, and the other end of the hole channel communicates with the air guide pipe. The sealing piece can abut against the end, away from the connecting part, of the bearing part under the action of gravity so as to block the hole channel. In the sediment collection process, the pile bottom sediment collector keeps the original form of sediment, and the collection rate is high; the sediment in the original form is collect