Method and apparatus for forming piles in place

摘要

A method for making piles apparatus for practicing the method of the invention are disclosed. The invention may be used to support the foundation of a structure, such as a building. The method draws one or more soil displacing members on a shaft down through a body of soil by turning a screw at the lower end of the shaft. The soil displacing members force soil out of a cylindrical region around the shaft. The cylindrical region is filled with grout to encapsulate and strengthen the shaft. The grout may be fed by gravity from a bath of grout around the shaft. The methods of the invention may be used to make stepped piers at much lower cost than existing methods. The invention provides methods for coating the screw portion of a screw pier with grout to protect the screw from the action of corrosive soils and to reinforce helical screws.