HOME 18" THICK-FLANGE DOUBLE TEE
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18 inch Double Tee X-Section

SECTION PROPERTIES
I  = 15203  in4 Zt  = 3269  in3 Zb  = 1139  in3 A  = 693  in2
W  = 75  psf Yt  = 4.65  in Yb  = 13.35  in    


ALLOWABLE SUPERIMPOSED LOAD (in pounds per square foot)
SIMPLE SPAN (in feet)
Number of ½" Ø strands per tee 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52    
4 (straight) 85 63 46 32 20                        
4 (harped) 92 69 51 37 25                        
6 (straight) 142 111 87 68 52 39 28                    
6 (harped) 164 130 104 82 65 50 38 28                  
8 (straight) 187 150 121 97 78 61 46 34 23                
8 (harped) 231 188 153 125 103 84 67 53 40 29 20            
10 (harped) 294 241 199 165 137 112 92 75 60 48 37 27          
12 (harped) 351 290 240 199 166 138 115 95 79 64 52 41 32 23      
14 (harped) 400 330 274 229 192 161 136 114 96 80 66 54 43 34 26    

NOTES:

  1. The minimum top flange reinforcement is WWF 4x4-W2.9/W2.9, and the maximum safe uniform load on the flange with minimum reinforcement is 180 psf. Additional flange reinforcement will be required for loads in excess of 180 psf.
  2. Interpolation between values shown is acceptable.  Do not extrapolate values into the blank spaces of the table.
  3. These Span-Load Tables are intended as an aid to preliminary sizing. Sound engineering judgement is required for the application of this information to specific design cases.
  4. Values in the lower left of the table in bold type represent conditions where shear reinforcement is required. See SHEAR in "Design Criteria..." for discussion.
  5. Values in the lower left of the table in bold red type represent conditions where (1) shear reinforcement is required and (2) top flange tension reinforcement is required in addition to the standard flange mesh.
  6. See "Design Criteria..." for definitions of HIGHLIGHTING. Highlighting not visible on printed copy (screen only).