C-sections and composite decks formed by cold-formed sheets for a system of composite reinforced concrete columns

Abstract

The present application relates to reinforced concrete columns classed in the category of reinforced concrete according to the NSR-10 and ACI-318 standards, in which the tubular channel is formed by sections with cold-roll sheets (CR) which form C-sections with a core and at least on skid which projects into the inner space of the column, coming into contact with the concrete. The skid comprises along its length a series of perforations through which concrete can pass, allowing a composite column to be formed once the concrete has set, in which steel and concrete work together and mutually strengthen their qualities to such an extent that the thickness of the sheet can be reduced, rendering the product economically viable. Moreover, the invention relates to the composite deck comprising these C-sections and a concrete core confined in the inner space of the tubular channel.

1 . A composite channel section formed from a steel sheet, comprising:
 a web; and p 1  one or two flanges projecting into the internal space of the column, coming into contact with the concrete, said flanges comprising:
 a series of perforations with a diameter ranging between 25 mm and 38 mm; and 
 a distance between a center of one perforation and an adjacent perforation, the distance being 1 to 2 times the diameter of the perforations. 
   
     
     
         2 . The composite channel section of  claim 1 , wherein the steel sheet is a Cold Roll (CR) type sheet. 
     
     
         3 . The composite channel section of  claim 2 , wherein the channel sections are produced in galvanized steel or stainless steel. 
     
     
         4 . The composite channel section of  claim 1 , wherein the thickness of the sheet ranges between 0.45 mm and 3 mm. 
     
     
         5 . The composite channel section of  claim 1 , having an L, C or U shape and a pair of flanges at each end. 
     
     
         6 . The composite channel section of  claim 1 , wherein the width of the web of the channel sections is between 1 mm and 150 mm. 
     
     
         7 . The composite channel section of  claim 1 , wherein the width of the flanges is between 50 mm and 75 mm. 
     
     
         8 . The composite channel section of  claim 7 , wherein the flanges are have a width of 75 mm. 
     
     
         9 . The composite channel section of  claim 1 , wherein the perforations are distributed equidistantly along a length of the flange, and are centered relative to the lateral edges of the flange. 
     
     
         10 . The composite channel section of  claim 9 , wherein the distance between the center of one perforation and an adjacent perforation is 75 mm and the distance between the center of the perforation and the edges of the flange is 37.5 mm. 
     
     
         11 . A composite decking comprising:
 a tubular channel comprising:   a web;   one or two flanges projecting into the internal space of the column, coming into contact with the concrete, said flanges comprising:
 a series of perforations with a diameter ranging between 25 mm and 38 mm; and 
 a distance between a center of one perforation and an adjacent perforation, the distance being 1 to 2 times the diameter of the perforations; and 
   a concrete core confined in the internal space of the tubular channel.   
     
     
         12 . The composite decking of  claim 11 , further comprising:
 four L-shaped composite channel sections, located at the corners, joined by their flanges to the flanges of four C-shaped composite channel sections that occupy a central part;   wherein the perforations of the adjacent flanges coincide.   
     
     
         13 . The composite decking of  claim 11 , further comprising:
 four U-shaped composite channel sections, joined together via their flanges.   
     
     
         14 . The composite decking of  claim 12 , wherein the flanges of the channel sections are provisionally joined by means of an adhesive-type epoxy resin or type 70XX welding, generating a vacuum within the same so as to form a tubular channel having the dimensions of the column. 
     
     
         15 . The composite decking of  claim 14 , wherein the flanges are finally joined through clamping by the sections of the concrete core that passes through the perforations creating a concrete bridge. 
     
     
         16 . The composite decking of  claim 11 , wherein the mixture for the concrete core has a compressive strength of 40 MPa. 
     
     
         17 . The composite decking of  claim 16 , wherein the concrete mixture comprises metallic fibers of circular section having anchor hooks at their ends, the fibers having a diameter of 075 mm±0.03 mm, a length of 60 mm±0.03 mm and minimum tensile strength of 1.100 MPa. 
     
     
         18 . The composite decking of  claim 17 , characterized in that the proportion of metallic fiber in the concrete mixture is 160 kg/m3. 
     
     
         19 . The composite decking of  claim 17 , wherein:
 the concrete mixture has a water/cement ratio=0.4;   further comprises a superplasticizer additive or a water-reducing additive based on modified polycarboxylates; and   has a consumption of 16 mL/kg of cement, and includes a coarse aggregate such as crushed stone, with a maximum size of 15 mm.   
     
     
         20 . A method of constructing composite decking, comprising:
 making channel sections in L, C, or U shapes, depending on the type of column desired;   temporarily joining the flanges of the channel sections by means of an adhesive or welding, guaranteeing that the perforations of the adjacent flanges coincide, so as to leave a hollow space through which the concrete may flow, and creating an empty space inside the channel sections that are joined to form the tubular channel;   filling the interior space of the tubular channel with concrete; and   waiting for the concrete to set, so that upon solidifying, the through sections of the concrete core that pass through the perforations generate bridges that permanently join the channel sections and consolidate the composite column of composite channel sections-concrete core.