Foundation structure

Abstract

This invention provides a foundation structure ( 10 ) cast from a settable material such as concrete and comprises a slab ( 12 ) having a particular generally annular non-rectangular circumferential outer profile. The foundation structure ( 10 ) is further provided with a plurality of intsecting primary beams ( 14 ) extending through a common central region of the slab ( 12 ); and a secondary annular circumferentially extending beam ( 16 ). The structure ( 10 ) is constructed by a method including the steps of forming a plurality of radially extending primary channels extending through a central foundation region of the building; forming a secondary annular circumferentially extending channel; providing a void former for defining a common central region of intersecting channels, through which the primary beams ( 14 ) extend after being cast; casting a settable material into the channels; and casting a slab of settable material integrally with the primary and secondary beams ( 14, 16 ).

1 . A foundation structure for a building of the type having a non-rectangular annular circumferential profile, the foundation structure comprising a plurality of radially extending primary beams of a settable material extending through a central foundation region of the building; and a slab of settable material cast integrally with the beams.  
     
     
         2 . A foundation structure according to  claim 1  wherein the building has a circular circumferential outer profile.  
     
     
         3 . A foundation structure according to  claim 1  wherein the foundation structure has an elliptic circumferential outer profile.  
     
     
         4 . A foundation structure according to  claim 1  wherein the foundation structure has a hexagonal circumferential outer profile.  
     
     
         5 . A foundation structure according to  claim 1  wherein the foundation structure has an octagonal circumferential outer profile.  
     
     
         6 . A foundation structure according to any one of the preceding claims wherein a secondary annular beam is provided along the circumference of the foundation structure.  
     
     
         7 . A foundation structure according to  claim 6  wherein an intermediate annular beam disposed concentrically with the secondary annular beam is provided between the secondary beam and said central region.  
     
     
         8 . A foundation structure according to  claim 1  wherein the beams extend through a common central point.  
     
     
         9 . A foundation structure according to  claim 8  wherein the common central point is formed by a void former encasing a central region of the beams.  
     
     
         10 . (Cancelled)  
     
     
         11 . A building having a foundation structure according to  claim 1 .  
     
     
         12 . A method of constructing a foundation structure for a building of the type having a non-rectangular annular circumferential profile, the method including the steps of forming a plurality of radially extending primary channels extending through a central foundation region of the building; casting a settable material into the channels to form a plurality of radially extending beams; and casting a slab of settable material integrally with the beams.  
     
     
         13 . A method of constructing a building according to  claim 12  which includes the further step of, prior to casting the beams, providing a void former for defining a common central region of intersecting channels, through which the beams extend after being cast.  
     
     
         14 . (Cancelled)  
     
     
         15 . A void former comprising a base and a plurality of walls extending from the base, the walls being arranged such that a plurality of radially extending channels intersecting in a common region are defined by the walls.  
     
     
         16 . (Cancelled).