Patent ID: 8079781

Claim:
A structural pier device, comprising: (a) a pier lead section being composed of an alloy steel tubular shaft member and having opposite ends; (b) a ground-penetrating member being affixed to one of said ends of said pier lead section, the other of said ends forming a terminal coupling end; (c) an integrally-fabricated composite pier extension member having a main shaft section and a terminal coupling section; (d) said main shaft section being composed of an alloy steel tubular shaft member; (e) said terminal coupling section being composed of a hardened alloy steel tubular member having a yield strength greater than about 125,000 pounds per square inch and exceeding that of said main shaft section by at least about 25,000 pounds per square inch, said coupling section being inertia friction welded to said main shaft section of said extension member; and (f) said coupling section of said extension member being adapted to mate with said terminal coupling end of said pier lead section.