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-STRUCTURAL SOLUTIONS, P.A. Project Amarr C- rage Doors No.: 2K -014 5509 -B West Friendly Avenue, Suite 103 Location Winston - Salem, NC Greensboro, North Carolina 27410 (336) 856 -2686 Date 9/11/00 Sheet 1 of 1 From Thomas L. Shelmerdine, PE Comparison of 16'x7' door and 15' -8 ". 15' -6 ", 15' -0 ". 14'. 12' and 10' wide doors The 16'x7' door is the size used in the tests. These calculations show that 15' -8 ", 15' -6 ", 15' -0 ", 14', 12' and 10' wide by 7' high doors of similar construction are structurally adequate. The design pressures and test pressures for "Components" as defined in the Building Code vary with the surface area of the item under investigation. The larger the area, the lower the pressure. Therefore, the required test pressures for the smaller doors are slightly larger than the tested door. The surface areas and required test pressures for each size door are tabulated below. Note that the pressures used in these calculations are larger than required by Code. The number of interior stiles with hinges for each door are also tabulated below. Because of the different widths, the tributary area to each interior hinge varies. All other components of the various doors are identical. ITEM 1 16'x7' 1 15' -8 "x7' 1 15' -6 "x7' 1 15'x7' I 14'x7' 12'x7' 1 10'x7' I Surface Area, sf 112 109.67 108.5 105 98 84 70 Test Pressure "X" psf 1 to 2% > "X" 1 to 2% > "X" 1 to 2% > "X" 1 to 2% > "X" 2 to 3% > "X" 4 to 5% > "X" Pressure to Use "X" psf 102% of 'X" 103% of "X" 104% of "X" 105% of "X' 110% of 'X" 110% of "X" Compare Strut 100% 15.67 15.5 15 14 * 12 10 * Stress to 16'x7' 102 % = 97.8% 103 % = 96.7% 104 % = 91.4% 105 % = 80.4% 110 % = 61.9% 110 % =43.0% No. Interior 3 3 3 3 4 3 2 Stiles w/ Hinges Tributary Area 21 "x48" 21 "x47" = 21'x46.5" = 21 "x45" = 21"x36" = 21'x36" = 21 "x36" = per Hinge, in = 1008 987 976.5 945 756 756 756 Compare Hinge 100% 987/1008 976.5/1008 * 945/1008 * 756/1008 * 756/1008 * 756/1008 Load to 16'x7' 102 % = 99.9% 103 % = 99.8% 104%=97.1% 105 % = 78.8% 110 % = 82.5% 110 % =82.5% The stress in the reinforcing struts is a function of the square of the length. The strut stresses in the 15' -8 ", 15' -6 ", 15' -0 ", 14', 12' and 10' wide doors are all Tess than the strut stress in the tested door. The load to each interior hinge is a function of the pressure and the tributary area to each hinge. The hinge loads of the 15' -8 ", 15' -6 ", 15' -0 ", 14', 12' and 10' wide doors are all less than the hinge load in the tested door. This comparison of tributary area also applies to the rollers, jamb brackets and other elements. CONCLUSION The 15' -8 ", 15' -6 ", 15' -0", 14', 12' and 10' wide by 7' high doors are structurally adequate,0 8' "` M9 the 16'x7' � , � - door. � +\�� Y* A;, 7.� ' . ti .�. ,4$&7 rws � - i r ••. R- 1 IA 14 00'