Foundation support system shaft coupler fabrication and assembly

Abstract

A modular foundation support system includes modular foundation support components including shafts provided with integrally formed coupler features on their respective distal ends. The coupler features are configured with a non-uniform wall thickness defining a plurality of sections of respectively different diameter to matingly couple the shafts to one another in a torque transmitting relationship. The coupler features may be integrally formed and fabricated on the distal end of each respective shaft.

What is claimed is: 
     
         1 . A support system for a building foundation, the support system comprising:
 a first elongated hollow shaft having a structural load bearing capacity to support the building foundation from a below-ground location, the first elongated hollow shaft having a first end comprising:   a receiving portion having a first axial length, a first wall thickness, a first uniform inner diameter extending along the first axial length, and at least one fastener hole for attaching the receiving portion to a second hollow shaft in the assembly of the support system; and   a seating portion extending from the receiving portion, the seating portion having a second axial length that is less than the first axial length, a second wall thickness that is different from the first wall thickness, a second uniform inner diameter that is smaller than the first uniform inner diameter, and a seating surface to complete the attachment of the second hollow shaft in the round receiving surface.   
     
     
         2 . The support system of  claim 1 , wherein the first wall thickness is less than the second wall thickness. 
     
     
         3 . The support system of  claim 2 , wherein the first end further comprises a shaft portion extending from the seating portion opposite the receiving portion, the shaft portion having a third wall thickness that is less than the second wall thickness. 
     
     
         4 . The support system of  claim 3 , wherein the shaft portion has a third uniform inner diameter that is greater than the second uniform inner diameter. 
     
     
         5 . The support system of  claim 1 , wherein the first elongated hollow shaft is fabricated from steel. 
     
     
         6 . The support system of  claim 1 , wherein the seating surface has a decreasing inner diameter extending between the first uniform inner diameter and the second inner diameter. 
     
     
         7 . The support system of  claim 1 , wherein the at least one fastener hole comprises at least one pair of fastener holes formed through the receiving section. 
     
     
         8 . The support system of  claim 7 , further comprising a bolt insertable through the at least one pair of fastener holes to attach the second hollow shaft. 
     
     
         9 . The support system of  claim 1 , wherein the receiving portion is integrally formed with at least one torque transmitting coupler feature therein. 
     
     
         10 . The support system of  claim 9 , wherein the at least one torque transmitting coupler feature is a rib or a groove. 
     
     
         11 . The support system of  claim 1 , further comprising a helical auger coupled to the first elongated hollow shaft at a distance from the first end. 
     
     
         12 . A foundation support system comprising:
 at least one structural forged steel shaft having an end comprising:   a receiving portion having a first axial length, a first wall thickness, a first uniform inner diameter extending along the first axial length, and a plurality of fastener holes for attaching the receiving portion to a second steel shaft in the assembly of the foundation support system; and   a seating portion having a second axial length that is less than the first axial length, a second wall thickness that is different from the first wall thickness, a second uniform inner diameter that is smaller than the first uniform inner diameter, and a seating surface to complete the attachment of the second steel shaft;   wherein the at least one structural forged steel shaft has a load bearing capacity to support a building foundation from a below ground location when attached to the second steel shaft.   
     
     
         13 . The foundation support system of  claim 12 , wherein the first wall thickness is less than the second wall thickness. 
     
     
         14 . The foundation support system of  claim 13 , wherein the end further comprises a shaft portion having a third wall thickness that is less than the second wall thickness, and wherein the seating portion is positioned between the receiving portion and the shaft portion. 
     
     
         15 . The foundation support system of  claim 14 , wherein the shaft portion has a third uniform inner diameter that is greater than the second uniform inner diameter. 
     
     
         16 . The foundation support system of  claim 12 , wherein the receiving portion further comprises a plurality of integrally formed torque transmitting features. 
     
     
         17 . The foundation support system of  claim 12 , further comprising a helical auger coupled to the at least one forged steel shaft. 
     
     
         18 . A foundation support system comprising:
 a forged steel shaft configured to provide structural support and load bearing capacity to a building foundation from a below ground location, the forged steel shaft comprising:   a receiving portion having a first axial length, a first wall thickness, a first uniform inner diameter extending along the first axial length, and at least one fastener hole for attaching the round receiving surface to a second steel shaft in the assembly of the foundation support system;   a seating portion having a second axial length that is less than the first axial length, a second wall thickness that is greater than the first wall thickness, a second uniform inner diameter that is smaller than the first uniform inner diameter, and a seating surface to complete the attachment of the second steel shaft in the round receiving surface; and   a shaft portion having a third wall thickness that is less than the second wall thickness, and a third uniform inner diameter that is greater than the second uniform inner diameter.   
     
     
         19 . The foundation support system of  claim 18 , further comprising a bolt attaching the forged steel shaft to the second steel shaft.