Post-grouting gravel pile with sand wall wing plates and construction method

The invention relates to a post-grouting gravel pile with sand wall wing plates. The post-grouting gravel pile with the sand wall wing plates is characterized by mainly comprising a grouting gravel pile, a plurality of sets of sand wall wing plates and precast reinforced concrete pile tips, wherein the sand wall wing plates are uniformly distributed along the ring direction of the grouting gravel pile and are connected with the grouting gravel pile to form a whole body, the top part of a pile body extends into a sound cushion layer, the precast reinforced concrete pile tips comprise a gravel pile tip and a sand wall pile tip and are respectively arranged at the bottoms of the gravel pile and a sand wall, a grouting pipe is preset in the middle of the grouting gravel pile body, and the bottom of the grouting pipe is connected with the precast pile tips. With the adoption of the post-grouting gravel pile, the performance of water drainage of a granular material during a prepressing period can be exerted, and the grout can also be grouted into the pile body by a grouting pipe according to the sedimentation condition to form a rigid composite pile type, thus increasing the effective reinforcing depth of a gravel pile foundation and realizing effective unification of a drainage consolidation method and a composite foundation method.