AC46-0210-R1 #16 January 27, 2010 Mr. Woods McRoy International Code Council Evaluation Service, Inc. Birmingham Regional Office 900 Montclair Road, Suite A Birmingham, AL 35213 Re: Proposed Acceptance Criteria for Cold-formed Steel Framing Members, Subject AC46-0210- R1 (WM/DM) Dear Mr. McRoy, Although the American Iron and Steel Institute (AISI) will not be able to send a representative to the Evaluation Committee hearing on February 3, 2010 we would like to comment on the proposed changes to AC46. We take exception to the requirement in the newly added section 3.2.3 which requires input and output data to be submitted for each and every value to be recognized in an evaluation report, even if the values are based on the same types of profiles or configurations. It is our understanding that compliance with such a requirement would mean that thousands of additional pages of documentation would have to be processed, scanned, mailed, reviewed, and approved. This extreme requirement would cause reports for cold-formed steel framing members to take months longer for the submitter to prepare and review, and the volume of data submitted would be overly burdensome on your clerical and reviewing staff as well. This additional time and effort would have little-to-no positive effect on the accuracy or quality of the final report. In addition, we are unaware of similar requirements for other structural products, which would make this requirement unfair to the cold-formed steel framing industry. We therefore request that you require that only representative samples of computer calculations be submitted; similar to what is required for hand calculations. Thank you for your consideration. Sincerely, 3810 Sydna Street Bethlehem, PA 18017 Phone: 610.691.6334 Email: jlarson@steel.org 1140 Connecticut Avenue NW Suite 705 Washington, DC 20036 Fax: 202.463.1039 Website: www.steel.org Jay W. Larson, P.E., F. ASCE Managing Director, Construction Technical Steel Market Development Institute a business unit of AISI 3810 Sydna Street Bethlehem, PA 18107-1048 tel: 610.691.6334 www.steel.org SMDI Construction Market Council Members: ArcelorMittal Dofasco ArcelorMittal USA Nucor Corporation Severstal North America, Inc. SSAB Americas Steelscape, Inc. United States Steel Corporation USS-POSCO Industries
AC46-0210-R1 #16
2001 North American Specification w/ 2004 Supplement ASD - DATE: 12/4/2006 SECTION DESIGNATION: 600S200-33 Single INPUT PROPERTIES: Web Height = 6.000 in Steel Thickness = 0.0346 in Top Flange = 2.000 in Inside Corner Radius = 0.0765 in Bottom Flange = 2.000 in Yield Stress, F y = 33.0 ksi Stiffening Lip = 0.625 in Ultimate Stress, F u = 45.0 ksi Punchout Width = 1.500 in F y With Cold-Work, F ya = 33.0 ksi Punchout Length = 4.000 in DETAILED SECTION PROPERTIES CALCULATIONS GROSS STRONG AXIS PROPERTIES - USING LINE METHOD Corner Properties Number of Corners = 4 Centerline Radius r' = R + t/2 = 0.094 in Centerline Length L C = π /2*r' = 0.147 in Distance from End of Web or Lip to CG of Corner Segment C = 0.637 * r' = 0.060 in Distance from Outside Edge of Flange to CG of Corner Segment C 3 = R+t-C = 0.051 in Element Flat Lengths Top Flange L TF gross = 2.0-(R + t)*2 = 1.778 in Web L Web gross = 6.0-(R + t)*2 = 5.778 in Bottom Flange L BF gross = 2.0-(R + t)*2 = 1.778 in Lips L Lip gross = 0.625-(R + t) = 0.514 in Sum of Lengths L i gross = L TF gross + L Web gross + L BF gross + 2*L Lip gross + 4*L C = 10.951 in Cross Sectional Area A = Σ L i gross *t = 0.379 in 2 Section Weight Wt = A*490 lb/ft 3 /144 in 2 /ft 2 = 1.289 lb/ft Element CG Distances to Top Fiber Top Flange Distance Y TF = t/2 = 0.017 in Web Distance Y WEB = h o /2 = 3.0 in Bottom Flange Distance Y BF = h o - t/2 = 5.983 in Top Lip Distance Y TLip = R + t + L Lip gross /2 = 0.368 in Bottom Lip Distance Y BLip = h o - (R + t + L Lip gross /2) = 5.632 in Top Corner Distance Y TC = C 3 = 0.051 in Bottom Corner Distance Y BC = h o -C 3 = 5.949 in Sum of Segment Lengths x Segment CG to Top Fiber Distance = Σ L i gross *Y i = 32.852 in 2 Sum of Segment Lengths x Segment CG to Top Fiber Distance 2 = Σ L i gross *Y i 2 = 142.432 in 3 Neutral Axis Distance from Top Fiber Y cg gross = ( Σ L i gross *Y i )/ Σ L i gross = 3.0 in Element Moment of Inertia about their Own Center of Gravity Web I XX Web = L web gross 3 /12 = 16.074 in 3 Lips I XX Lip = L Lip gross 3 /12 = 0.011 in 3 Sum of Moment of Inertia of Line Elements I' xx = Σ L i gross *Y i 2 + I xx web + 2*I xx Lips - Σ L i gross *Y cg gross 2 = 59.973 in 3 Moment of Inertia of Gross Section I xx gross = I' xx *t = 2.075 in 4 Section Modulus of Top Flange S xx Top = I xx /Y cg gross = 0.692 in 3 Section Modulus of Bottom Flange S xx Bottom = I xx /(h o -Y cg gross ) = 0.692 in 3 Controls Radius of Gyration about XX Axis r x = (I xx /A) 1/2 = 2.340 in
DETAILED SECTION PROPERTIES CALCULATIONS for 600S200-33 Single 12/4/2006 Page 2 GROSS WEAK AXIS PROPERTIES - USING LINE METHOD (Continued) Element CG Distances to Outside Face of Web Top Flange Distance X TF = TF/2 = 1.0 in Web Distance X WEB = t /2 = 0.017 in Bottom Flange Distance X BF = BF/2 = 1.0 in Top Lip Distance X TLip = TF - t/2 = 1.983 in Bottom Lip Distance X BLip = BF -t/2 = 1.983 in Inside Corner Distance X IC = C 3 = 0.051 in Top Outside Corner Distance X OC Top = TF -C 3 = 1.949 in Bottom Outside Corner Distance X OC Btm = BF -C 3 = 1.949 in Sum of Segment Lengths x Segment CG to Outside Face of Web = Σ L i gross *X i = 6.283 in 2 Sum of Segment Lengths x Segment CG to Outside Face of Web 2 = Σ L i gross *X i 2 = 8.717 in 3 Neutral Axis Distance to Outside Face of Web X cg gross = ( Σ L i gross *X i )/ Σ L i gross = 0.574 in Element Moment of Inertia about their Own Center of Gravity Top Flange I YY TF = L TF gross 3 /12 = 0.468 in 3 Bottom Flange I YY BF = L BF gross 3 /12 = 0.468 in 3 Sum of Moment of Inertia of Line Elements I' yy = Σ L i gross *X i 2 + I YY TF + I YY BF - Σ L i gross *X cg gross 2 = 6.049 in 3 Moment of Inertia of Gross Section I yy gross = I' yy *t = 0.209 in 4 Section Modulus of Web Face S yy Web = I yy /X cg gross = 0.365 in 3 Section Modulus of Lip Face S yy Lip = I yy /(TF -X cg gross ) = 0.147 in 3 Controls Radius of Gyration about YY Axis r y = (I yy /A) 1/2 = 0.743 in TORSIONAL PROPERTIES BASED ON GROSS SECTION Element Lengths for Shear Center Calculations Web L Web SC = a = 6.0- t = 5.965 in Flange L Flg SC = b = 2.0- t = 1.965 in Lips L Lip SC = c = 0.625- t/2 = 0.608 in Centerline of Web to Shear Center Distance m = b*t/(12*i XX gross )*( 6*c*a 2 + 3*b*a 2-8*c 3 ) = 0.922 in Distance from Shear Center to Centroid along X Axis x 0 = m + X CG Gross - t/2 = -1.479 in Polar Radius of Gyration about Shear Center r 0 = (r x 2 + r y 2 + x o 2 ) 1/2 = 2.866 in Coefficient β = 1-(x 0 /r o ) 2 = 0.734 NASPEC Eqn C4.2-3 St. Venant Torsion Constant J ( x 1000) = 1/3*t 3 * Σ L i gross = 0.151 in 4 (x 1000) Warping Constant C w Calculations based on Wei-Wen Yu, Cold Formed Steel Design, 2nd Edition (John Wiley and Sons, 1991), p. 967 Warping Constant ω c1 = x cg gross *A gross *a 2 /t(b 2 /3 + m SC 2 - m SC b) = 70.587 Warping Constant ω c2 = A gross /(3t)*(m sc 2 a 3 + b 2 c 2 (2c + 3a) ) = 758.892 Warping Constant ω c3 = -I xx gross m sc 2 /t*(2a + 4c ) = -732.917 Warping Constant ω c4 = m sc c 2 /3*(8b 2 c + 2m sc (2c(c-a) + b(2c-3a))) = -6.1 Warping Constant ω c5 = b 2 a 2 /6*(( 3c + b)( 4c + a) - 6c 2 ) = 677.988 Warping Constant ω c6 = -m SC 2 a 4 /4 = -269.398 Warping Constant C w = t 2 / A gross * Σ ω i = 1.577in 6
DETAILED SECTION PROPERTIES CALCULATIONS for 600S200-33 Single 12/4/2006 Page 3 EFFECTIVE STRONG AXIS FLEXURAL PROPERTIES - USING LINE METHOD Effective Flexural Property Stress Level F ya = 33.0 ksi Neutral Axis from Top Fiber Y CG eff = 3.126 in (See Calculations Below) Check Web Effective Width per NASPEC Section B2.3 & B2.4 Flat Width of Web w =5.778 in per NASPEC Figure B2.3-1 Ratio Web to Punchout Width d o /h = 0.260 < 0.38 Therefore per NASPEC Section B2.4(a) Use Section B2.3(a) Assuming No Holes Exist Stress at End of Segment f 1 = (Y CG eff - R - t)/y CG eff *F ya = 31.83 ksi per NASPEC Figure B2.3-1 Stress at End of Segment f 2 = -(h o - Y CG eff - R - t)/y CG eff *F ya = -29.17 ksi per NASPEC Figure B2.3-1 Stress Ratio Ψ = f 2 /f 1 = 0.916 NASPEC Equation B2.3-1 Buckling Coefficient k = 4 + 2(1+ Ψ ) 3 + 2(1 + Ψ ) = 21.9 NASPEC Equation B2.3-2 Poisson's Ratio for Steel µ = 0.3 per NASPEC pg 31 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 )*(t/w) 2 = 20.95 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (f 1 /F cr ) 1/2 = 1.233 > 0.673 NASPEC Equation B2.1-4 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.666 NASPEC Equation B2.1-3 Effective Width b e = ρ *w = 3.851 in NASPEC Equation B2.1-2 Calculated Width b 1 = b e / (3+ Ψ ) = 0.983 in NASPEC Equation B2.3-3 Effective Width b 2 = b e /2 = 1.925 in NASPEC Equation B2.3-4 Web Distance for b 1 Y b1 = b 1 /2 + R + t = 0.603 in Effective Width b 2e = b 2 + Compression Portion = b 2 + (w -Y cg eff - R - t) = 4.688 in Web Distance for b 2e Y b2 = h o - R - t - b 2e /2 = 3.545 in Check Top (Compression ) Flange Effective Width per NASPEC Section B4.2 Flat Width of Flange w =1.778 in per NASPEC Figure B4-2 Constant S = 1.28*(E/F ya ) 1/2 = 38.27 NASPEC Equation B4-1 Case with w/t = 51.384 > 0.328*S = 12.553 Adequate Moment of Inertia I a = 0.000228 NASPEC Equation B4.2-10 Stiffening Lip Moment of Inertia I s = t*w 3 Lip /12 = 0.000391 per NASPEC Section B4.2 Coefficient (R I ) = I s /I a = (1.713<= 1.0) =1.0 NASPEC Equation B4.2-9 Coefficient n = (0.582-w/t/(4*S)) >= 1/3 = 0.333 NASPEC Equation B4.2-11 Plate Buckling Coefficient k = (4.82-5*D/w)(R I ) n + 0.43 <= 4 = 3.492 NASPEC Table B4.2 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 35.27 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (F ya /F cr ) 1/2 = 0.967 > 0.673 NASPEC Equation B2.1-4 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.799 NASPEC Equation B2.1-3 Effective Width b = ρ *w = 1.420 in NASPEC Equation B2.1-2 Top (Compression) Flange Distance Y TF eff = t/2 = 0.017 in Effective Bottom (Tension) Flange Width b = w = 1.778 in Bottom (Tension) Flange Distance Y BF eff = h 0 - t/2 = 5.983 in Effective Corner Width b = L C = 0.147 in per Page 1 Top Corner Distance Y TC eff = C 3 = 0.051 in Bottom Corner Distance Y BC eff = h 0 - C 3 = 5.949 in Check Lip Effective Widths Flat Width of Lip w =0.514 in per NASPEC Figure B3.1-1 Stress at End of Segment f 1 = (Y CG eff - R - t)/y CG eff *F ya = 31.83 ksi per NASPEC Figure B3.2-1 (a) Stress at End of Segment f 2 = (Y CG eff - R - t - w)/y CG eff *F ya = 26.40 ksi per NASPEC Figure B3.2-1 (a) Stress Ratio Ψ = f 2 /f 1 = 0.830 NASPEC Equation B3.2-1 Buckling Coefficient k = 0.578/( Ψ +0.34) = 0.494 per NASPEC Section B3.2-2 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 59.7 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (f 1 /F cr ) 1/2 = 0.730 > 0.673 NASPEC Equation B2.1-4 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.957 NASPEC Equation B2.1-3 Effective Width b = ρ *w*(r I ) = 0.492 in NASPEC Equation B2.1-2 and B4.2-7 Top (Compression) Lip Distance Y TF eff = R + t + b/2= 0.357 in Effective Bottom (Tension) Lip Width b = w = 0.514 in Bottom (Tension) Lip Distance Y BF eff = h 0 - R - t - b/2 = 5.632 in Sum of Effective Widths b i eff = b TF eff + b 1e eff + b 2e eff + b BF eff + b TLip eff + b BLip eff + 4*L C = 10.464 in Sum of Effective Segment Lengths x Effective Segment CG to Top Fiber Distance = Σ b i eff *Y i eff = 32.71 in 2 Sum of Effective Segment Lengths x Effective Segment CG to Top Fiber Distance 2 = Σ b i eff *Y i eff 2 = 149.693 in 3
DETAILED SECTION PROPERTIES CALCULATIONS for 600S200-33 Single 12/4/2006 Page 4 EFFECTIVE STRONG AXIS FLEXURAL AND SHEAR PROPERTIES - USING LINE METHOD (Continued) Neutral Axis Distance from Top Fiber Y cg eff = ( Σ b i eff *Y i eff )/ Σ b i eff = 3.126 in Element Moment of Inertia about their Own Center of Gravity Web I b1 Web = b 1e 3 /12 = 0.0792 in 3 Web I b2 Web = b 2e 3 /12 = 8.5871 in 3 Lip I b TLip = b TLip eff 3 /12 = 0.0099 in 3 Lip I b BLip = b BLip eff 3 /12 = 0.0113 in 3 Sum of Moment of Inertia of Line Elements I' xx eff = Σ L i eff *Y i eff 2 + I bi web + I b ilip - Σ L i eff *Y cg eff 2 = 56.13 in 3 Moment of Inertia of Effective Section I xx eff = I' xx *t = 1.942 in 4 Section Modulus of Top Flange S xx Top = I xx /Y cg eff = 0.621 in 3 Controls Section Modulus of Bottom Flange S xx Bottom = I xx /(h o -Y cg eff ) = 0.676 in 3 Calculated Allowable Moment M a = S xx *F ay / Ω b = 20.50/1.67 = 12.28 in*k Shear Capacity per NASPEC Section C3.2 Flat Depth of Web h = 5.778 in per NASPEC Section C3.2.1 Depth to Thickness Ratio h/t = 5.778 in/ 0.035 in = 167.0 Buckling Coefficient k v = 5.34 per NASPEC Section C3.2.1 For Calculated h/t > 1.51(Ek v /F y ) 1/2 = 104.3 Nominal Shear Stress F v = 0.904Ek v /(h/t) 2 = 5.11 ksi NASPEC Equation C3.2.1-4 Area of Web Element A w = ht = 5.778 in*0.0346 in = 0.200 in 2 per NASPEC Section C3.2.1 Nominal Shear Strength V n = A w F v = 1020.9 lb NASPEC Equation C3.2.1-1 Calculated Allowable Strong Axis Shear away from Punchout V a = V n / Ω v = 1020.9 lb/ 1.6 = 638.1 lb Distance for Non-Circular Holes c = h/2 - d O /2 = 2.139 in NASPEC Equation C3.2.2-4 Ratio of Punchout Distance to Thickness c/t = 2.14 in/0.0346 in = 61.8 >= 54 Therefore q s = 1.0 NASPEC Equation C3.2.2-1 Calculated Allowable Strong Axis Shear at Punchout V a = V n / Ω v *q s = 1020.9 lb/ 1.6 * 1.00 = 638.1 lb EFFECTIVE STRONG AXIS PROPERTIES FOR DEFLECTION - USING PROCEDURE 1 OF NASPEC B2.1 Effective Deflection Property Stress Level F d = 17.988 ksi Note that F d = M a /S xx Fd where S xx Fd is Determined for the Stress Level F d Neutral Axis from Top Fiber Y CG I = 3.015 in (See Calculations Below) Check Web Effective Width per NASPEC Section B2.3 & B2.4 Flat Width of Web w =5.778 in per NASPEC Figure B2.3-1 Per NASPEC Section B2.4(b) Use Section B2.3(b) Assuming No Holes Exist Stress at End of Segment f 1 = (Y CG I - R - t)/y CG I *f d = 17.33 ksi per NASPEC Figure B2.3-1 Stress at End of Segment f 2 = -(h o - Y CG I - R - t)/y CG I *f d = -17.14 ksi per NASPEC Figure B2.3-1 Stress Ratio Ψ = f 2 /f 1 = 0.990 NASPEC Equation B2.3-1 Buckling Coefficient k = 4 + 2(1+ Ψ ) 3 + 2(1 + Ψ ) = 23.7 NASPEC Equation B2.3-2 Poisson's Ratio for Steel µ = 0.3 per NASPEC pg 31 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 )*(t/w) 2 = 22.69 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (f d /F cr ) 1/2 = 0.874 > 0.673 NASPEC Equation B2.1-4 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.856 NASPEC Equation B2.1-3 Effective Width b e = ρ *w = 4.947 in NASPEC Equation B2.1-2 Calculated Width b 1 = b e / (3+ Ψ ) = 1.240 in NASPEC Equation B2.3-3 Calculated Width b 2 = b e /2 = 2.473 in NASPEC Equation B2.3-4 However, Since b 1 + b 2 = 3.713 > Y cg - R - t) = 2.904 Set b 2 = 0 and b 1 = w = 5.778 in per NASPEC Section B2.3 (a) Web Distance for b 1 Y b1 = b 1 /2 + R + t = 3.000 in
DETAILED SECTION PROPERTIES CALCULATIONS for 600S200-33 Single 12/4/2006 Page 5 EFFECTIVE STRONG AXIS PROPERTIES FOR DEFLECTION - USING PROCEDURE 1 OF NASPEC B2.1 Check Top (Compression ) Flange Effective Width per NASPEC Section B4.2 Flat Width of Flange w =1.778 in per NASPEC Figure B4-2 Constant S = 1.28*(E/f d ) 1/2 = 51.84 NASPEC Equation B4-1 Case with w/t = 51.384 > 0.328*S = 17.002 Adequate Moment of Inertia I a = 0.000167 NASPEC Equation B4.2-10 Stiffening Lip Moment of Inertia I s = t*w 3 Lip /12 = 0.000391 per NASPEC Section B4.2 Coefficient (R I ) = I s /I a = (2.346<= 1.0) =1.0 NASPEC Equation B4.2-9 Coefficient n = (0.582-w/t/(4*S)) >= 1/3 = 0.334 NASPEC Equation B4.2-11 Plate Buckling Coefficient k = (4.82-5*D/w)(R I ) n + 0.43 <= 4 = 3.492 NASPEC Table B4.2 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 35.27 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (f d /F cr ) 1/2 = 0.714 > 0.673 NASPEC Equation B2.1-4 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.969 NASPEC Equation B2.1-3 Effective Width b = ρ *w = 1.722 in NASPEC Equation B2.1-2 Top (Compression) Flange Distance Y TF I = t/2 = 0.017 in Effective Bottom (Tension) Flange Width b = w = 1.778 in Bottom (Tension) Flange Distance Y BF I = h 0 - t/2 = 5.983 in Effective Corner Width b = L C = 0.147 in per Page 1 Top Corner Distance Y TC I = C 3 = 0.051 in Bottom Corner Distance Y BC I = h 0 - C 3 = 5.949 in Check Lip Effective Widths Flat Width of Lip w =0.514 in per NASPEC Figure B3.1-1 Stress at End of Segment f 1 = (Y CG I - R - t)/y CG I *F ya = 17.33 ksi per NASPEC Figure B3.2-1 (a) Stress at End of Segment f 2 = (Y CG I - R - t - w)/y CG I *F ya = 14.26 ksi per NASPEC Figure B3.2-1 (a) Stress Ratio Ψ = f 2 /f 1 = 0.823 NASPEC Equation B3.2-1 Buckling Coefficient k = 0.578/( Ψ +0.34) = 0.497 per NASPEC Section B3.2-2 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 60.1 ksi NASPEC Equation B2.1-5 Slenderness Factor λ = (f 1 /F cr ) 1/2 = 0.537 <= 0.673 NASPEC Equation B2.1-4 Effective Width b = w*(r I ) = 0.514 in NASPEC Equation B2.1-1 and B4.2-7 Top (Compression) Lip Distance Y TF I = R + t + b/2= 0.368 in Effective Bottom (Tension) Lip Width b = w = 0.514 in Bottom (Tension) Lip Distance Y BF I = h 0 - R - t - b/2 = 5.632 in Sum of Effective Widths b i I = b TF I + b 1e I + b 2e I + b BF I + b TLip I + b BLip I + 4*L C = 10.895 in Sum of Effective Segment Lengths x Effective Segment CG to Top Fiber Distance = Σ b i I *Y i I = 32.851 in 2 Sum of Effective Segment Lengths x Effective Segment CG to Top Fiber Distance 2 = Σ b i I *Y i I 2 = 142.432 in 3 Neutral Axis Distance from Top Fiber Y cg I = ( Σ b i I *Y i I )/ Σ b i I = 3.015 in Element Moment of Inertia about their Own Center of Gravity Web I b1 Web = b 1e 3 /12 = 16.0742 in 3 Lip I b TLip = b TLip I 3 /12 = 0.0113 in 3 Lip I b BLip = b BLip I 3 /12 = 0.0113 in 3 Sum of Moment of Inertia of Line Elements I' xx I = Σ L i I *Y i I 2 + I bi web + I b ilip - Σ L i I *Y cg I 2 = 59.476 in 3 Moment of Inertia for Deflection I xx I = I' xx *t = 2.058 in 4
2001 North American Specification w/ 2004 Supplement ASD - DATE: 6/23/2007 SECTION DESIGNATION: 362S162-54 Single INPUT PROPERTIES: Web Height = 3.625 in Steel Thickness = 0.0566 in Top Flange = 1.625 in Inside Corner Radius = 0.0849 in Bottom Flange = 1.625 in Yield Stress, F y = 50.0 ksi Stiffening Lip = 0.500 in Ultimate Stress, F u = 65.0 ksi Punchout Width = 1.500 in F y With Cold-Work, F ya = 50.0 ksi Punchout Length = 4.000 in ALLOWABLE COMBINED AXIAL AND BENDING LOAD - SIMPLE SPAN INPUT PARAMETERS Member Length L= 10.00 ft Uniform Load = 50.0 psf Selected Member Spacing = 16 inches on center Lateral Load Multiplier for Stress Checks = 1.00 Axial Load Multiplier for Stress Checks = 1.00 Load Multiplier for Deflection = 0.70 Capacity Calculations are Based on the Following Physical Constraints: Shear Capacity Based on Unpunched Member Web Web Stiffeners May be Required at Supports, Check by Others Continuous Laterally Braced Flanges Between Supports (for Bending Loads) Weak Axis and Torsional Bracing Spaced at 48 inches (for Axial Loads) CALCULATED PARAMETERS Uniformly Distributed Load on Member for Stress Checks W = 66.67 plf Uniformly Distributed Load on Member for Deflection Check W = 46.67 plf Check Shear Calculated Member Shear at Support V= W*L/2= 333 lb Calculated Allowable Shear V a = 3372 lb Check Moment Calculated Member Moment at Midspan M= W*L 2 /8= 833 ft*lb Calculated Allowable Moment M a = 1107 ft*lb Check Axial Load Calculated Controlling Allowable Axial Load P = 724 lb Factor of Safety Ω c = 1.80 Calculated Nominal Axial Stress F n = 20.76 ksi (see Page 2) Calculated Effective Area at F n A e = 0.335 in 2 (see Page 2) Calculated Nominal Axial Load P n = A e *F n = 6,966 lb Calculated Allowable Axial Load P a = P n / Ω c = 3,870 lb (without Bending Loads) Check Bending and Axial Load Interactions (Controls) C m = 1.0 Unbraced Length K x L x = 120.0 in Buckling Capacity P ex = π 2 EI x gross /(K x L x ) 2 = 17.65 kips α x = 1- Ω c *P/P ex = 0.926 P ao = 8,210 lb (see Page 3) P/P a + (C m *M)/(M a * α x )= 1.000 P/P ao + M/M a = 0.841 per NASPEC Section C5.2.1.3(b) NASPEC Equation C5.2.1-6 NASPEC Equation C5.2.1-4 NASPEC Equation C5.2.1-1 NASPEC Equation C5.2.1-2 Check Deflection Calculated Strong Axis Effective Moment of Inertia I xx = 0.873 in 4 Calculated Deflection = 5/384*W*L 4 /(E*I) =0.408 in = L/294
CALCULATED EFFECTIVE PROPERTIES AT F n Page 2 Calculate Stress F n Unbraced Length K x L x = 120.0 in K x L x /r x = 83.4 Unbraced Length K y L y = 48 in K y L y /r y = 79.4 Unbraced Torsional Length K t L t = 48 in Modulus of Elasticity of Steel E = 29,500 ksi NASPEC pg 18 Shear Modulus of Steel G = 11,300 ksi NASPEC pg 21 Elastic Flexural Buckling Stresses About Major Axis F ex = π 2 E/(K x L x /r x ) 2 = 41.8 ksi NASPEC Eqn C4.1-1 About Minor Axis F ey = π 2 E/(K y L y /r y ) 2 = 46.2 ksi NASPEC Eqn C4.1-1 Factor σ ex = π 2 E/(K x L x /r x ) 2 = 41.8 ksi NASPEC Eqn C3.1.2.1-6 Factor σ t = 1/(Ar o 2 ) * (GJ+ π 2 EC w /(K t L t ) 2 )= 36.51 ksi NASPEC Eqn C3.1.2.1-8 Coefficient β = 1-(x 0 /r 0 ) 2 = 0.597 NASPEC Eqn C4.2-3 Torsional-Flexural Buckling Stress F e = 1/(2 β )*(( σ ex + σ t )-(( σ ex + σ t ) 2-4 β σ ex σ t ) 1/2 )= 23.8 ksi NASPEC Eqn C4.2-1 Factor λ c = (F y /F e ) 1/2 = 1.45 NASPEC Eqn C4-4 Calculated Nominal Axial Stress F n = (0.658^ λ c 2 )F y = 20.76 ksi NASPEC Eqn C4-2 Check Web Effective Width per NASPEC Section B2.1 and D-4 Flat Width of Web w =3.34 in per NASPEC Figure B2.1-1 Net Flat Width of Web Each Side of Punchout w' =0.92 in Buckling Coefficient k =0.43 per NASPEC Section B3.1 (a) Slenderness Factor λ = (F n /F cr ) 1/2 = 0.69 NASPEC Equation B2.1-4 Poisson's Ratio for Steel µ = 0.3 per NASPEC pg 31 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w') 2 = 43.30 ksi NASPEC Equation B2.1-5 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.99 NASPEC Equation B2.1-3 Effective Width b = ρ *2*w' = 1.81 in NASPEC Equation B2.1-2 Check Flange Effective Width per NASPEC Section B4.2 Flat Width of Flange w =1.34 in per NASPEC Figure B4-2 Constant S = 1.28*(E/F n ) 1/2 = 48.25 NASPEC Equation B4-1 Case with w/t = 23.71 > 0.328*S = 15.825 Adequate Moment of Inertia I a = 0.000018 NASPEC Equation B4.2-10 Stiffening Lip Moment of Inertia I s = t*w 3 Lip /12 = 0.000217 per NASPEC Section B4.2 Coefficient (R I ) = I s /I a = (12.156<= 1.0) =1.0 NASPEC Equation B4.2-9 Coefficient n = (0.582-w/t/(4*S)) >= 1/3 = 0.459 NASPEC Equation B4.2-11 Plate Buckling Coefficient k = (4.82-5*D/w)(R I ) n + 0.43 <= 4 = 3.387 NASPEC Table B4.2 Slenderness Factor λ = (f n /F cr ) 1/2 = 0.36 NASPEC Equation B2.1-4 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 160.64 ksi NASPEC Equation B2.1-5 Effective Width b = w = 1.34 in NASPEC Equation B2.1-1 Check Lip Effective Width per NASPEC Section B3.1 & B4.2 Flat Width of Lip w =0.359 in Buckling Coefficient k =0.43 Slenderness Factor λ = (f n /F cr ) 1/2 = 0.27 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 285.8 ksi Effective Width b = w*(r I ) = 0.36 in Check Corner Effective Length Centerline Radius r' =0.113 in Effective Length b = π r'/2 = 0.18 in per NASPEC Figure B3.1-1 per NASPEC Section B3.1(a) NASPEC Equation B2.1-4 NASPEC Equation B2.1-5 NASPEC Equations B2.1-1 and B4.2-7 Effective Area per AISI Section B A e = (2*b Flange + 2*b Lip + b Web + 4*b Corner )*t = 0.335 in 2
CALCULATED EFFECTIVE PROPERTIES AT F y Page 3 Check Web Effective Width per NASPEC Section B2.1 and D-4 Flat Width of Web w =3.34 in per NASPEC Figure B2.1-1 Net Flat Width of Web Each Side of Punchout w' =0.92 in Buckling Coefficient k =0.43 per NASPEC Section B3.1 (a) Slenderness Factor λ = (F y /F cr ) 1/2 = 1.07 NASPEC Equation B2.1-4 Poisson's Ratio for Steel µ = 0.3 per NASPEC pg 31 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w') 2 = 43.30 ksi NASPEC Equation B2.1-5 Slenderness Coefficient ρ = (1-0.22/ λ )/ λ = 0.74 NASPEC Equation B2.1-3 Effective Width b = ρ *2*w' = 1.36 in NASPEC Equation B2.1-2 Check Flange Effective Width per NASPEC Section B4.2 Flat Width of Flange w =1.34 in per NASPEC Figure B4-2 Constant S = 1.28*(E/F y ) 1/2 = 31.09 NASPEC Equation B4-1 Case with w/t = 23.71 > 0.328*S = 10.198 Adequate Moment of Inertia I a = 0.000336 NASPEC Equation B4.2-10 Stiffening Lip Moment of Inertia I s = t*w 3 Lip /12 = 0.000217 per NASPEC Section B4.2 Coefficient (R I ) = I s /I a = (0.647<= 1.0) =0.647 NASPEC Equation B4.2-9 Coefficient n = (0.582-w/t/(4*S)) >= 1/3 = 0.391 NASPEC Equation B4.2-11 Plate Buckling Coefficient k = (4.82-5*D/w)(R I ) n + 0.43 <= 4 = 2.923 NASPEC Table B4.2 Slenderness Factor λ = (F y /F cr ) 1/2 = 0.60 NASPEC Equation B2.1-4 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 138.63 ksi NASPEC Equation B2.1-5 Effective Width b = w = 1.34 in NASPEC Equation B2.1-1 Check Lip Effective Width per NASPEC Section B3.1 Flat Width of Lip w =0.359 in Buckling Coefficient k =0.43 Slenderness Factor λ = (F y /F cr ) 1/2 = 0.42 Plate Elastic Buckling Stress F cr = k* π 2 *E/(12(1- µ 2 ))*(t/w) 2 = 285.8 ksi Effective Width b = w*(r I ) = 0.23 in per NASPEC Figure B3.1-1 per NASPEC Section B3.1(a) NASPEC Equation B2.1-4 NASPEC Equation B2.1-5 NASPEC Equation B2.1-1 and B4.2-7 Check Corner Effective Length Centerline Radius r' =0.113 in Effective Length b =0.18 in Effective Area per AISI Section B A ey = (2*b Flange + 2*b Lip + b Web + 4*b Corner )*t = 0.296 in 2 P ao = A ey *F y / Ω c = 8,210 lb per NASPEC Section C5.2.1
AC46-0210-R1 #16 January 27, 2010. Mr. Woods McRoy International Code Council Evaluation Service, Inc. Birmingham Regional Office 900 Montclair Road, Suite A Birmingham, AL 35213 Agenda item 16: AC46: Acceptance Criteria for Cold-Formed Steel Framing Members Dear Mr. McRoy, Since SSMA submitted our January 19 letter on AC46, it has come to our attention that the submittal requirements in the new section 3.2.3 are overly burdensome, and will place cold-formed steel (CFS) framing at a competitive disadvantage to non-steel framing products approved under other Acceptance Criteria. Suggested changes: Calculations: When section properties and/or design parameters are determined by calculations, calculations shall be submitted for each and every a representative set of values to be recognized in the evaluation report. Calculations shall be signed and sealed by the engineer responsible for the calculations. When calculations are generated using a computer program, the computer program and version or edition shall be identified. The computer calculations shall include a sample input for each distinct section type the input and output for every member and every value to be recognized in the evaluation report. The current proposed language would turn hundreds of pages of data to thousands of pages, and have no effect on the accuracy of the final product. Our biggest concern: it is unfair to have this requirement placed on CFS framing products, and not on products of wood, concrete, structural steel, or other structural materials. If ICC-ES staff feels that full calculation input and output are required, it should be a general requirement for all structural product submittals, and not just for one type of product. Thank you again for the opportunity to comment; feel free to call or email to discuss. I plan on attending the February hearings to represent SSMA. Sincerely, STEEL STUD MANUFACTURERS ASSOCIATION Don Allen, P.E. Technical Director Headquarters Office Technical Services Office 800 Roosevelt Road, Building C Suite 312 Glen Ellyn, IL 60137 1480 Cobbham Road Thomson, GA 30824-4141 (630) 942-6592 Fax: (630) 790-3095 (706) 597-8076 (202) 497-9375 cell info@ssma.com ssma@steelframing.org www.ssma.com
AC46-0210-R1 #16
December 29, 2009 TO: PARTIES INTERESTED IN EVALUATION REPORTS ON COLD- FORMED STEEL FRAMING MEMBERS SUBJECT: Proposed Acceptance Criteria for Cold-formed Steel Framing Members, Subject AC46-0210-R1 (WM/DM) Dear Madam or Sir: ICC-ES is requesting changes to AC46 as follows: Hearing Information: Wednesday, February 3, 2010 8:00 a.m. Sheraton Gateway Hotel Los Angeles 6101 West Century Boulevard Los Angeles, California 90045 (888) 627-7104 1. Update AC46 to include the 2009 International Building Code (IBC) and the 2009 International Residential Code (IRC). The changes involve updating the editions of codes and standards referenced in the acceptance criteria (AC). The changes between the editions of the codes and standards are editorial, for the most part. The technical changes that staff has been able to identify are minor in nature and do not have any substantive effect. As an example, the definition for non-structural member in the Cold-Formed Steel Framing- General Provisions (AISI-S200 [formally AISI-General]) has been revised to allow transverse loads of not greater than 10 psf from 5 psf. The difference between a structural member and a non-structural member is the type of steel that is allowed for use. Non-structural steel is allowed a lesser galvanized coating (G40 vs. G60) and has only required yield strengths, whereas structural steel has requirements for yield strength, tensile strength and elongation. Since the changes between the 2006 code requirements and the 2009 code requirements are minor, staff is requesting to use the updated requirements as the basis for recognition of cold-formed steel framing members under the 2006 International Building Code and the 2006 International Residential Code. 2. Delete provisions for field manufacturing of cold-formed steel members found in Section 6.1.2. There are no current reports recognizing field manufacturing of cold-formed steel members nor does ICC-ES have any applications requesting field manufacturing of cold-formed steel members.
AC46-0210-R1 2 3. Delete provisions specific to the 1997 Uniform Building Code (UBC). Industry has indicated they believe there is no need to continue with provisions in AC46 for the UBC, and supports removing it from the AC. 4. Add Section 3.2.3 to clarify requirements for engineering calculations. You are cordially invited to submit written comments on agenda items, or to attend the Evaluation Committee hearing and present verbal comments. If you wish to contribute to the hearing, please note the following: 1. Written comments that are received by the Los Angeles business/regional office by January 19, 2010, will be forwarded to the committee prior to the hearing, and will be posted on the ICC-ES web site shortly after the comment deadline. 2. Written comments received up to ten days before the meeting, and staff memos responding to comments, will be posted to the web site on January 28, 2010. 3. ICC-ES is no longer providing printed copies at the meeting of proposed acceptance criteria, staff memos or public comments. These documents will be available on a limited number of CDs at the meeting, for uploading to computers; and ICC-ES will make arrangements with the hotel business center to have hard copies available for photocopying. 4. Written comments that miss the deadline noted in item (1), above, will only be available at the meeting if you provide 35 copies, collated, stapled, and threehole punched, either at the meeting itself or to the Los Angeles business/regional office by January 28, 2010. 5. If you plan to speak for more than 15 minutes, or offer a visual presentation lasting longer, you should notify ICC-ES staff as far as possible in advance. There will be a computer, projector, and screen available at the meeting for anyone wishing to make a visual presentation, and presentations in most cases will need to be in PowerPoint format. Also, ICC-ES will need to be provided with your presentation at least a half-hour before the start of the relevant meeting session (morning or afternoon) on either a CD or a flash card. 6. If you have any special needs related to a presentation, you should contact ICC-ES staff well in advance of the meeting. 7. Any visual aids for viewing at committee meetings (charts, overhead transparencies, slides, videos, electronic presentations, etc.) will be permitted only if a copy is provided to ICC-ES, before the presentation, in a medium that can be retained with other records of the meeting.
AC46-0210-R1 3 8. Any materials submitted for committee consideration are considered nonconfidential and available for public discussion, as noted in Section 2.7 of the ICC-ES Rules of Procedure for the Evaluation Committee. 9. Prior to the meeting, you should refrain from trying to communicate directly with committee members about agenda items, either verbally or in writing. Committee members reserve the right to refuse such communications. Your cooperation with these guidelines is much appreciated, as is your interest in the deliberations of the Evaluation Committee. If you have any questions, please contact the undersigned at (800) 423-6587, extension 5686, or David Musselwhite, P.E., Senior Staff Engineer, at extension 5681. You may also reach us by e-mail at es@icc-es.org. Yours very truly, WFM/raf Enclosures Woods McRoy, P.E. Senior Staff Engineer cc: Evaluation Committee
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ICC EVALUATION SERVICE, INC., RULES OF PROCEDURE FOR THE EVALUATION COMMITTEE appealed in accordance with the ICC-ES Rules of Procedure for Appeal of Acceptance Criteria or the ICC-ES Rules of Procedure for Appeals of Evaluation Committee Technical Decisions. 5.0 COMMITTEE BALLOTING FOR ACCEPTANCE CRITERIA 5.1 Acceptance criteria may be issued without a public hearing following a 30-day public comment period and a majority vote for approval by the Evaluation Committee when, in the opinion of ICC-ES staff, one or more of the following conditions have been met: 1. The subject is nonstructural, does not involve life safety, and is addressed in nationally recognized standards or generally accepted industry standards. 2. The subject is a revision to an existing acceptance criteria that requires a formal action by the Evaluation Committee, and public comments raised were resolved by staff with commenters fully informed. 3. Other acceptance criteria and/or the code provide precedence for the revised criteria. 5.2 Negative votes must be based upon one or more of the following, for the ballots to be considered valid and require resolution: a. Lack of clarity: There is insufficient explanation of the scope of the acceptance criteria or insufficient description of the intended use of the product or system; or the acceptance criteria is so unclear as to be unacceptable. (The areas where greater clarity is required must be specifically identified.) b. Insufficiency: The criteria is insufficient for proper evaluation of the product or system. (The provisions of the criteria that are in question must be specifically identified.) c. The subject of the acceptance criteria is not within the scope of the applicable codes: A report issued by ICC- ES is intended to provide a basis for approval under the codes. If the subject of the acceptance criteria is not regulated by the codes, there is no basis for issuing a report, or a criteria. (Specifics must be provided concerning the inapplicability of the code.) d. The subject of the acceptance criteria needs to be discussed in a public hearings. The committee member requests additional input from other committee members, staff or industry. 5.3 An Evaluation Committee member, in voting on an acceptance criteria, may only cast the following ballots: Approved Approved with Comments Negative: Do Not Proceed 6.0 COMMITTEE COMMUNICATION Direct communication between committee members, and between committee members and an applicant or concerned party, with regard to the processing of a particular acceptance criteria or evaluation report shall take place only in a public hearing of the Evaluation Committee. Accordingly: 6.1 Committee members receiving an electronic ballot should respond only to the sender (staff). Committee members who wish to discuss a particular matter with other committee members, before reaching a decision, should ballot accordingly and bring the matter to the attention of ICC-ES staff, so the issue can be placed on the agenda of a future committee meeting. 6.2 Committee members who are contacted by an applicant or concerned party on a particular matter that will be brought to the committee will refrain from private communication and will encourage the applicant or concerned party to forward their concerns through the ICC- ES staff in writing, and/or make their concerns known by addressing the committee at a public hearing, so that their concerns can receive the attention of all committee members.# Effective March 18, 2008 2
www.icc-es.org (800) 423-6587 (562) 699-0543 A Subsidiary of the International Code Council PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR COLD-FORMED STEEL FRAMING MEMBERS AC46 Proposed December 2009 Previously approved February 2007, June 2006, October 2004, January 2001 March 2000, April 1998, January 1994 PREFACE Evaluation reports issued by ICC Evaluation Service, Inc. (ICC-ES), are based upon performance features of the International family of codes and other widely adopted code families, including the Uniform Codes, the BOCA National Codes, and the SBCCI Standard Codes. Section 104.11 of the International Building Code reads as follows: The provisions of this code are not intended to prevent the installation of any materials or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety. Similar provisions are contained in the Uniform Codes, the National Codes, and the Standard Codes. ICC-ES may consider alternate criteria, provided the report applicant submits valid data demonstrating that the alternate criteria are at least equivalent to the criteria proposed in this document, and otherwise meet the applicable performance requirements of the codes. Notwithstanding that a product, material, or type or method of construction meets the requirements of the criteria proposed in this document, or that it can be demonstrated that valid alternate criteria are equivalent to the criteria in this document and otherwise meet the applicable performance requirements of the codes, ICC-ES retains the right to refuse to issue or renew an evaluation report, if the product, material, or type or method of construction is such that either unusual care with its installation or use must be exercised for satisfactory performance, or malfunctioning is apt to cause unreasonable property damage or personal injury or sickness relative to the benefits to be achieved by the use of the product, material, or type or method of construction. Acceptance criteria are developed for use solely by ICC-ES for purposes of issuing ICC-ES evaluation reports.
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR COLD- FORMED STEEL FRAMING MEMBERS 1.0 INTRODUCTION 1.1 Purpose: The purpose of this criteria is to establish requirements for cold-formed steel framing members to be recognized in an ICC Evaluation Service, Inc. (ICC-ES), evaluation report under the 2006 and 2009 International Building Code (IBC), and the 2006 and 2009 International Residential Code (IRC) and the 1997 Uniform Building Code (UBC). Basis of recognition under the IBC is the United States of America provisions of AISI-NAS S100 and AISI General S200 as referenced in IBC Sections 1604.3.3 and 2210. Bases of recognition under the IRC are IRC Sections R301.1.3, R505, R603, and R804. Basis of recognition under the UBC is UBC Chapter 22, Division VI or VII, or AISI 1996 Specifications. 1.2 Scope: This acceptance criteria applies to coldformed steel framing members used in light-frame construction 1.3 Codes and Referenced Standards: 1.3.1 2009 International Building Code (IBC), International Code Council. 1.3.2 2009 International Residential Code (IRC), International Code Council. 1.3.3 2006 International Building Code (IBC), International Code Council. 1.3.4 2006 International Residential Code (IRC), International Code Council. 1.3.5 1997 Uniform Building Code (UBC). 1.3.5 AISI-NAS-01 S100-07, North American Specification for Design of Cold-formed Steel Structural Members, 2001 2007 edition, with 2004 supplement, published by the American Iron and Steel Institute (AISI). The United States provisions of AISI-NAS S100 are applicable under this criteria. 1.3.6 AISI General-04 S200-07, AISI North American Standard for Cold-Formed Steel Framing General Provisions, American Iron and Steel Institute (AISI). 1.3.8 AISI WSD-04 S211-07, AISI North American Standard for Cold-Formed Steel Framing Wall Stud Design, American Iron and Steel Institute (AISI). 1.3.9 AISI Header-04, AISI Standard for Cold- Formed Steel Framing Header Design, American Iron and Steel Institute (AISI). 1.3.10 AISI Lateral-04, AISI Standard for Cold- Formed Steel Framing Lateral Design, American Iron and Steel Institute (AISI). 1.3.11 AISI Truss-04, AISI Standard for Cold-Formed Steel Framing Truss Design, American Iron and Steel Institute (AISI). 1.3.12 Specification for the Design of Cold-Formed Steel Structural Members, 1996 edition, American Iron and Steel Institute (AISI) (referred to as 1996 Specifications). 1.3.7 ASTM A 370-97a 09ae1, Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM International. 1.3.8 ASTM A 924-99 07, Specification for General Requirements for Steel Sheet, Metallic Coated by the Hot- Dip Process, ASTM International. 1.3.9 TS 9-05, Standard Test Method for Determining the Web Crippling Strength of Cold-Formed Steel Beams, American Iron and Steel Institute (AISI). 1.4 Definitions: Definitions are located in the referenced codes and standards. 2.0 GENERAL The following information shall be submitted: 2.1 Data concerning material specifications; section properties; maximum allowable heights; maximum allowable spans and/or maximum allowable loads; and lateral, mechanical or material bracing requirements. 2.2 Method of field identification. 2.3 Quality control program. 2.4 Data in support of an application for recognition only under the IRC shall verify compliance with Sections R505, R603 and R804 of the IRC and the requirements noted in this criteria except for Section 4.0. 2.5 Testing Laboratories: Testing laboratories shall comply with Section 2.0 of the ICC-ES Acceptance Criteria for Test Reports (AC85) and Section 4.2 of the ICC-ES Rules of Procedures for Evaluation Reports. 2.6 Test Reports: Test reports shall comply with AC85. Details describing the test configuration, test methods and test procedures, including load application rate, shall be identified in the test report. 3.0 TEST AND PERFORMANCE REQUIREMENTS 3.1 Material Specifications: 3.1.1 Steel: Steel specifications shall comply either with Section A2 of the AISI -NAS S100 and Section A3 of the AISI General S200, for the IBC and IRC; or with Section A.3 of the AISI 1986 ASD Specifications or AISI 1991 LRFD Specifications, as referenced in UBC Chapter 22, Division VII or VI, respectively; with Section A.3 of the 1996 Specifications, for the UBC. Nonstructural grades of steel shall be limited to interior nonload-bearing walls with lateral loads of 5 10 psf (240 480 Pa) or less. 3.1.2 Thickness: Minimum steel thicknesses shall comply with or with Section A2.4 of AISI-NAS S100, and Section A5.1 of AISI General S200; or with Section A3.4 of either the 1986 ASD Specifications; 1991 LRFD Specifications; 1996 Specifications. Other thicknesses may be considered, provided substantiating data showing compliance with the applicable code and this criteria are submitted. 3.1.3 Protective Coating: For use with the IBC and IRC, a minimum of G60 (or equivalent) is required for all applications with the exception of minimum G40 (or 2
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR COLD-FORMED STEEL FRAMING MEMBERS equivalent) for interior nonload-bearing walls with lateral loads of 5 10 psf (480 Pa) or less. 3.2 Cold-formed Steel Framing Members: Evaluation reports on cold-formed steel framing members shall address the section properties and design approach as applicable: 3.2.1 Section Properties: Section properties shall be determined in accordance with AISI-NAS S100 for recognition under the IBC; and 1986 ASD Specifications, 1991 LRFD Specifications or 1996 Specifications for recognition under the UBC. Structural properties data for steel members shall include the minimum information noted in Appendix B A of this criteria. Information on additional properties is optional and can be furnished. 3.2.2 Structural Performance: Capacity of members shall be determined in accordance with Chapters C and D of AISI-NAS S100 for recognition under the IBC; and Chapters C and D of the 1986 ASD Specifications, 1991 LRFD Specifications, or 1996 Specifications for recognition under the UBC. For members that exceed limitations specified in the applicable specifications AISI S100 or do not conform to the requirements of applicable specifications AISI S100, full-scale tests are necessary to determine applicable strength and stiffness. See Section 4.2 (4.3 for web crippling) of this criteria. 3.2.3 Calculations: When section properties and/or design parameters are determined by calculations, calculations shall be submitted for each and every value to be be recognized in the evaluation report. Calculations shall be signed and sealed by the engineer responsible for the calculations. When calculations are generated using a computer program, the computer program and version or edition shall be identified. The computer calculations shall include the input and output for every member and every value to be recognized in the evaluation report. When calculations are computer-generated, a set of handgenerated confirmatory calculations shall be submitted. The hand generated calculations shall be for one of each type of member to be recognized in the report. 4.0 DESIGN AND TESTING METHODS 4.1 Design Methods: This section is for cold-formed steel members that can be designed in accordance with Chapters C and D of AISI-NAS S100 for recognition under the IBC; and Chapters C and D of the 1986 ASD Specifications, 1991 LRFD Specifications, or 1996 Specifications for recognition under the UBC. Data concerning section properties, maximum allowable heights, spans and/or loads shall be submitted showing compliance with AISI-NAS S100 for recognition under the IBC; and UBC Chapter 22, Division VI or VII, or 1996 Specification, for recognition under the UBC. The analytical approach noted in Appendix A of this criteria can be used as a supplement to UBC Chapter 22, Division VI or VII, or 1996 Specification when appropriate. 4.2 Testing Methods: For members whose strength and stiffness cannot be calculated in accordance with Chapters C and D of AISI-NAS S100 used under the IBC and Chapters C and D of the 1986 ASD Specifications, 1991 LRFD Specifications or 1996 Specifications used under the UBC, testing shall be conducted in accordance with Section F1 of the AISI-NAS S100 used under the IBC and of the 1986 ASD Specifications, 1991 LRFD Specifications or 1996 Specifications used under the UBC, except for web crippling. Web crippling shall be tested in accordance with Section 4.3 below. Alternatively, under the IBC and IRC, design strength [allowable design strength] and stiffness may be determined by rational analysis based on appropriate theory and engineering judgment when supported by applicable test data. Specifically, design strength [allowable design strength] shall be determined from calculated nominal strength [resistance] by applying the resistance factors [factors of safety] of Section A1.1(b) A1.2(b) of the AISI-NAS S100. Test data shall demonstrate that strength and stiffness are not less than the nominal strength and stiffness predicted by the analysis. Testing programs under Section 4.2 of this criteria shall be submitted to the ES staff for review and acceptance prior to any testing being performed. The number of test specimens and test procedures and rate of loading shall be included in the test program submittal. 4.3 Web Crippling Tests: 4.3.1 Testing shall be conducted in accordance with AISI TS-9 on three similar specimens. Two series are required for each assembly: one series for interior reactions and a second series for end reactions. The load rate used under AISI TS-9 shall be reported. Both end reactions and interior reactions shall be evaluated in accordance with the conditions set forth in the applicable specification. The tested bearing width will be the minimum width recognized in the evaluation report. For member profiles available in multiple thicknesses, only the least minimum thickness in each profile is required to be tested. 4.3.2 Conditions of Acceptance: The members shall be loaded to failure or dysfunctional distortions and the loads causing web crippling shall be recorded. The determination of nominal resistance, R n, shall be based on Sections F1 of AISI-NAS S100 used under the IBC and Sections F1 of the 1986 ASD Specifications, 1991 LRFD Specifications or 1996 Specifications used under the UBC. For ASD, the allowable design strength, R a, is as follows: where: R a = R n /Ω. Ω = 1.6 ϕ For LRFD, equation F1.1-1 of AISI-NAS S100 applies under the IBC, and equation F1-1 in the 1991 LRFD Specifications or equation F1.1-1 in the 1996 Specifications applies under the UBC. The results shall be compared to the design equations in Section C3.4 of AISI-NAS S100 for use under the IBC, and Section C3.4 of the 1986 ASD Specifications, 1991 LRFD Specifications or 1996 Specifications for use under the UBC. The lowest result, from either testing or calculations, will determine the allowable value noted in the evaluation report. Where design capacities are derived from testing, the value will apply to heavier greater thicknesses. If the calculated web crippling value is the 3