Composite and support structures

Abstract

A method of constructing a composite structure comprises the steps of: (i) attaching light gauge sheeting to a plurality of joists that have been sufficiently closely spaced so that the sheeting is able to support a cementitious slab that has formed a composite structure with the sheeting and joists; (ii) forming the cementitious slab on the sheeting to form the composite structure; and (iii) supporting the joists until the cementitious slab has sufficiently cured.

1 . A method of constructing a composite structure comprising the steps of:
 (i) attaching light gauge sheeting to a plurality of joists that have been sufficiently closely spaced so that the sheeting is able to support a cementitious slab that has formed a composite structure with the sheeting and joists;   (ii) forming the cementitious slab on the sheeting to form the composite structure; and   (iii) supporting the joists until the cementitious slab has sufficiently cured.   
   
   
       2 . A method as claimed in  claim 1  wherein the sheeting is attached to the joists by a plurality of self drilling, self tapping fasteners. 
   
   
       3 . A method as claimed in  claim 2  wherein, after attaching the sheeting to the joists, each fastener extends up into the slab formed on the sheeting. 
   
   
       4 . A method as claimed in  claim 2  wherein each fastener is passed though a sleeve that, through engagement thereof by a head of the fastener, fixes the sheeting against a respective joist during formation and curing of the slab. 
   
   
       5 . A method as claimed in  claim 1  wherein each joist is of an open web construction incorporating top and bottom chords interconnected by web members. 
   
   
       6 . A method as claimed in  claim 5  wherein the web members are aligned generally perpendicular to the top and bottom chords, and external faces of the web members are welded to the chords at spacings along the joist that are equal to a depth of the joist. 
   
   
       7 . A method as claimed in  claim 1  wherein each joist is a beam that comprises a planar elongate web that interconnects opposing torsionally rigid elongate hollow flanges. 
   
   
       8 . A method as claimed in  claim 1  wherein components of each joist and the sheeting are each formed of light gauge steel. 
   
   
       9 . A method as claimed in  claim 5  wherein the sheeting is attached to the joists by a plurality of self drilling, self tapping fasteners, and the fasteners are inserted into a top chord. 
   
   
       10 . A method as claimed in  claim 1  wherein ends of each joist are fastened between opposing flanges of a channel section. 
   
   
       11 . A method as claimed in  claim 10  wherein the joist ends are fastened to the channel section by self drilling, self tapping fasteners which extend through the channel and into the joist ends. 
   
   
       12 . A method as claimed in  claim 1  wherein in step (iii) the joists are supported with supports during curing of the cementitious slab to form the composite structure, which supports are removed once the cementitious slab has sufficiently cured. 
   
   
       13 . A shear member for a composite structure that comprises a plurality of joists which underlie and support a cementitious slab in the structure, the shear member being fixable to a respective joist to project upwardly therefrom such that in use the shear member becomes partially embedded in the slab, the shear member comprising a sleeve that is located on a shank of the member whereby, when the shear member is fixed to a respective joist, the sleeve is retained on the shank by a head of the shear member, the sleeve being connected to reinforcing which in use is embedded in the cementitious slab. 
   
   
       14 . A member as claimed in  claim 13  wherein the joists underlie and support a decking and the cementitious slab is located on the decking in the structure, the shear member being fixable through the decking to its respective joist, with the shear member head acting on the sleeve to urge it against the decking to fix the decking against the joist. 
   
   
       15 . A member as claimed in  claim 14  wherein the decking is a light gauge steel roof or wall cladding. 
   
   
       16 . A member as claimed in  claim 13  that is in the form of a self drilling, self tapping fastener. 
   
   
       17 . A member as claimed in  claim 13  that is adapted for use with a composite structure having light gauge sheeting attached to the plurality of joists. 
   
   
       18 . A support structure comprising:
 a plurality of joists, each joist comprising either:
 a top chord and a bottom chord interconnected by web members in an open web construction; or 
 a beam that comprises a planar elongate web interconnecting opposing torsionally rigid elongate hollow flanges; and 
   at least one channel section that has a top flange and a bottom flanges interconnected by a web;
 wherein the plurality of joists are supported by the at least one channel section, the joists projecting from the at least one channel section and having one end thereof disposed between the top flange the bottom flanges, whereby the top chord or one of the hollow flanges is secured to the top flange, and the bottom chord or an other of the hollow flanges is secured to the bottom flange, respectively. 
   
   
   
       19 . A support structure as claimed in  claim 18  wherein the at least one channel section comprises light gauge steel and the joists are secured to the channel section by self drilling, self tapping fasteners. 
   
   
       20 . A support structure as claimed in  claim 18  wherein, in the joists of open web construction, the web members are aligned generally perpendicular to the top and bottom chords, and external faces of the web members are welded to the chords at spacings along the joist that are equal to a depth of the joist. 
   
   
       21 . A composite structure comprising:
 a support structure according to  claim 18 ; and   a cementitious slab supported on the plurality of joists.   
   
   
       22 . A composite structure comprising:
 a plurality of joists; and   a cementitious slab, formed, cured and supported on the plurality of joists.   
   
   
       23 . A structure as claimed in  claim 22  wherein the joists underlie and support a decking and the cementitious slab is located on the decking. 
   
   
       24 . A method as claimed in  claim 7  wherein the sheeting is attached to the joists by a plurality of self drilling, self tapping fasteners, and the fasteners are inserted into a top hollow flange of each joist.