Waterproof construction method for PC composite pile enclosure structure

The invention discloses a PC composite pile enclosure structure which is composed of first steel pipe piles, Larsen steel sheet piles, second steel pipe piles, steel enclosing purlins, pull rods, bracket supports, composite geomembranes, geogrids and geotechnical cloth. The first steel pipe pile and the Larsen steel sheet pile are assembled and combined into a lock catch structure through a locking opening to be arranged on the upstream side. The second steel pipe pile is arranged on the downstream side. Pull rod holes are formed in the steel pipe pile 1 and the steel pipe pile 2; the steel enclosing purlin is arranged above the bracket bracket; the invention further provides a waterproof construction method of the PC composite pile enclosure structure, and the waterproof construction method comprises the steps of laying a composite geomembrane, a geogrid and geotechnical cloth, constructing a waterproof curtain wall, performing compaction grouting construction and the like. A series of problems that a tradit