ASTM A572 Grade, 50 ksi STEEL BEAM CONVERSIONS TO WESTERN SPECIES GLULAM Glued Laminated Timber Design...

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ASTM A572 Grade, 50 ksi STEEL BEAM CONVERSIONS TO WESTERN SPECIES GLULAM Glued Laminated Timber Design Values 2400 Fbx= Ex= 1,800,000 Steel Section W W W 6 x 9 8 x 10 8 x 15 W 12 x 14 W 12 x 16 W 12 x 19 W 10 x 22 W 12 x 22 W 14 x 22 W 12 x 26 W 14 x 26 W 16 x 26 W 12 x 30 W 14 x 30 W 16 x 31 W 14 x 34 W 18 x 35 W 16 x 40 W 21 x 44 W 18 x 50 W 21 x 50 W 18 x 55 W 21 x 62 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 - - x X x x x X X X X X X X X X X X X X X X X X psi psi 13 1/2 15 18 Glulam Sizes to Substitute for Use in Floor Systems Co = 1.0 21 22 1/2 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 5 1/8 5 1/8 5 1/8 x 5 1/8 x x x X 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 X 5 1/8 x X X X X X 10 1/2 12 15 16 1/2 18 19 1/2 21 22 1/2 24 25 1/2 27 27 28 1/2 28 1/2 31 1/2 Steel Design Values (AISC, 9th edition, ASD) ksi 50 0.66 * Fy 29,000 31 1/2 34 1/2 37 1/2 F₁ = E = 6 3/4 6 3/4 6 3/4 X X X 6 3/4 X 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 6 3/4 6 3/4 x X X 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 X 6 3/4 x 6 3/4 X 6 3/4 x 9 10 1/2 13 1/2 15 15 18 18 19 1/2 21 22 1/2 22 1/2 24 24 25 1/2 27 27 30 31 1/2 36 37 1/2 39 40 1/2 46 1/2 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 x - - - ksi - x x x x X X X X X X X X X X X X X X X X Glulam Sizes to Substitute for Use in Roof Systems with Snow Loads CD= 1.15 12 13 18 19 21 24 13 1/2 19 1/2 5 1/8 x 5 1/8 X 5 1/8 x X 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 x X x x 5 1/8 5 1/8 5 1/8 X X 5 1/8 x 5 1/8 x 5 1/8 5 1/8 5 1/8 X x x x x x 5 1/8 X 5 1/8 x American Institute of Timber Construction X X X 9 12 13 1/2 15 16 1/2 18 19 1/2 21 22 1/2 24 24 25 1/2 25 1/2 27 28 1/2 28 1/2 31 1/2 34 1/2 39 40 1/2 -- 6 3/4 X 6 3/4 X 6 3/4 6 3/4 6 3/4 6 3/4 6 3/4 6 3/4 X 6 3/4 6 3/4 X x X X x 6 3/4 6 3/4 X 6 3/4 X 6 3/4 x 6 3/4 x X X 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 x x 6 3/4 X 6 3/4 X 6 3/4 X 9 10 12 15 15 16 16 10 1/2 16 1/2 16 1/2 18 19 1/2 21 21 22 1/2 22 1/2 24 25 1/2 25 1/2 28 1/2 30 34 1/2 36 36 37 1/2 43 1/2 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 -- - C-- x x x x x x x X X X X X X X 12 13 1/2 16 1/2 19 1/2 19 1/2 22 1/2 24 Glulam Sizes to Substitute for Use in Roof Systems with Non-Snow Loads CD = 1.25 - 11 11 Glulam Beam Dimensions Are in Inches 5 1/8 x 5 1/8 X x x 5 1/8 x x 5 1/8 5 1/8 5 1/8 5 1/8 x 5 1/8 x Simple Span Beam Dry Service Conditions 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x X 9 12 13 1/2 15 16 1/2 18 19 1/2 19 1/2 21 22 1/2 24 24 24 25 1/2 27 28 1/2 30 33 37 1/2 39 40 1/2 40 1/2 6 3/4 x X 6 3/4 6 3/4 X 6 3/4 X 6 3/4 6 3/4 x x 6 3/4 X 6 3/4 x 6 3/4 x 63/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 6 3/4 6 3/4 X x x 6 3/4 X 6 3/4 x 6 3/4 X 6 3/4 x Table Specifications: These sizes are for dry service condition of use. Reverse use of this table to convert from glued laminated timber sizes to steel sections is non-conservative in all cases and is NOT PERMITTED. Smaller glued laminated timber sizes may be possible with engineering calculations based on actual span and loading conditions. Glued laminated timber beam sizes are based on a span to depth (L/d) ratio of 21. When the span to depth ratio is larger, sizes should be determined by engineering calculations. To determine glued laminated timber beam sizes, Fox was adjusted by the volume factor. It is assumed that all beams are adequately braced for lateral stability. Tabulated beam sizes have been checked for adequacy in flexure and deflection. It is the responsibility of the designer to check for adequacy in shear. A minimum glued laminated timber depth of 6 inches is used in this table. Standard glued laminated timber sizes are used in this table. While these design conversions have been prepared in accordance with recognized engineering principles and are based on accurate technical data, conversions should not be used without competent examination and verification of the accuracy, suitability, and applicability by a qualified design professional. AITC MAKES NO REPRESENTATION OR WARRANTY, EXPRESSED OR IMPLIED, THAT THE INFORMATION CONTAINED HEREIN IS SUITABLE FOR ANY GENERAL OR SPECIFIC USE OR IS FREE FROM INFRINGEMENT OF ANY PATENT OR COPYRIGHT. ANY USER OF THIS INFORMATION ASSUMES ALL RISK AND LIABILITY ARISING FROM SUCH USE. 9 10 1/2 12 15 15 16 1/2 16 1/2 16 1/2 18 19 1/2 21 21 21 22 1/2 24 24 27 28 1/2 33 34 1/2 34 1/2 36 40 1/2 Background Information The table included with this exam converts A572 Grade 50 steel beam sections to Western Species glulam member sizes from the 24F-1.8E stress class. In the 9th edition Steel Manual, the ASD available flexural strength of steel beams was M' = (0.66F,)S where F, 50 ksi for A572 steel and S is the section modulus. For example, a W6x9 has section modulus S-5.56 in³, making its ASD available flexural strength M'-0.66(50 ksi) (5.56 in³) 184 kip-in-15.3 kip-ft. The glulam sizes that can be substituted for each steel W-section are listed for use in floor systems (CD=1.0), roof systems with snow loads (CD=1.15), and roof systems with non- snow (construction) loads (CD-1.25). For example, in a floor system with Cp-1.0, any of the following glulams from the 24F-1.8E stress class can be substituted for a W6x9 . 3 1/8 x 13 1/2 (6-3.125 inch, d=13.5 inch) • 5 1/8 x 10 1/2 (b-5.125 inch, d-10.5 inch) .6 3/4 x 9 (b-6.75 inch, d-9.0 inch) In other words, these glulams have the same or greater available flexural strength compared to the W6x9. Make note of the following from the Table Specifications: • The glulam sizes are based on dry service conditions, CM = 1. Although not stated, normal temperatures (C-1) also apply. • The glulam sizes are based on adequate bracing for lateral stability (C₁=1). • The glulam sizes are based on adjusting the design bending stress, For by the volume factor, Cy. • In computing the volume factor, a span to depth ratio, L/d 21 is assumed for all glulams in the table. For example, for a 6 3/4 x 15 glulam, the span length used in computing its volume factor is L-21d-21(15 inch)-315 inch 26.25 ft. The table assumes all members are loaded on their narrow face (Cfu-1), bent about their strong axis. The members are neither curved nor tapered (Ce and C, both equal 1). Ulti- mately, the only adjustment factors that apply in computing the glulam sizes in this table are Cy and CD F = FbxCpCv Cy is the computed volume factdor and Cp is specified in the table. Calculate the adjusted bending strength of the equivalent glulam. Use Cp=1. F psi ba Calculate the ASD available flexural strength of the equivalent glulam. M' kip-ft Calculate the ASD available shear strength of the equivalent glulam. Assume Cur-1. V' = kip Calculate the required bearing area for a concentrated load of P-20 kip applied per- pendicular to the wide face of the lams. Assume Co=1. A₁ > in² ASTM A572 Grade, 50 ksi STEEL BEAM CONVERSIONS TO WESTERN SPECIES GLULAM Glued Laminated Timber Design Values 2400 Fbx= Ex= 1,800,000 Steel Section W W W 6 x 9 8 x 10 8 x 15 W 12 x 14 W 12 x 16 W 12 x 19 W 10 x 22 W 12 x 22 W 14 x 22 W 12 x 26 W 14 x 26 W 16 x 26 W 12 x 30 W 14 x 30 W 16 x 31 W 14 x 34 W 18 x 35 W 16 x 40 W 21 x 44 W 18 x 50 W 21 x 50 W 18 x 55 W 21 x 62 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 - - x X x x x X X X X X X X X X X X X X X X X X psi psi 13 1/2 15 18 Glulam Sizes to Substitute for Use in Floor Systems Co = 1.0 21 22 1/2 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 5 1/8 5 1/8 5 1/8 x 5 1/8 x x x X 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 X 5 1/8 x X X X X X 10 1/2 12 15 16 1/2 18 19 1/2 21 22 1/2 24 25 1/2 27 27 28 1/2 28 1/2 31 1/2 Steel Design Values (AISC, 9th edition, ASD) ksi 50 0.66 * Fy 29,000 31 1/2 34 1/2 37 1/2 F₁ = E = 6 3/4 6 3/4 6 3/4 X X X 6 3/4 X 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 6 3/4 6 3/4 x X X 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 X 6 3/4 x 6 3/4 X 6 3/4 x 9 10 1/2 13 1/2 15 15 18 18 19 1/2 21 22 1/2 22 1/2 24 24 25 1/2 27 27 30 31 1/2 36 37 1/2 39 40 1/2 46 1/2 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 x - - - ksi - x x x x X X X X X X X X X X X X X X X X Glulam Sizes to Substitute for Use in Roof Systems with Snow Loads CD= 1.15 12 13 18 19 21 24 13 1/2 19 1/2 5 1/8 x 5 1/8 X 5 1/8 x X 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 5 1/8 x X x x 5 1/8 5 1/8 5 1/8 X X 5 1/8 x 5 1/8 x 5 1/8 5 1/8 5 1/8 X x x x x x 5 1/8 X 5 1/8 x American Institute of Timber Construction X X X 9 12 13 1/2 15 16 1/2 18 19 1/2 21 22 1/2 24 24 25 1/2 25 1/2 27 28 1/2 28 1/2 31 1/2 34 1/2 39 40 1/2 -- 6 3/4 X 6 3/4 X 6 3/4 6 3/4 6 3/4 6 3/4 6 3/4 6 3/4 X 6 3/4 6 3/4 X x X X x 6 3/4 6 3/4 X 6 3/4 X 6 3/4 x 6 3/4 x X X 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 X 6 3/4 x x 6 3/4 X 6 3/4 X 6 3/4 X 9 10 12 15 15 16 16 10 1/2 16 1/2 16 1/2 18 19 1/2 21 21 22 1/2 22 1/2 24 25 1/2 25 1/2 28 1/2 30 34 1/2 36 36 37 1/2 43 1/2 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 3 1/8 -- - C-- x x x x x x x X X X X X X X 12 13 1/2 16 1/2 19 1/2 19 1/2 22 1/2 24 Glulam Sizes to Substitute for Use in Roof Systems with Non-Snow Loads CD = 1.25 - 11 11 Glulam Beam Dimensions Are in Inches 5 1/8 x 5 1/8 X x x 5 1/8 x x 5 1/8 5 1/8 5 1/8 5 1/8 x 5 1/8 x Simple Span Beam Dry Service Conditions 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 X 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x 5 1/8 x X 9 12 13 1/2 15 16 1/2 18 19 1/2 19 1/2 21 22 1/2 24 24 24 25 1/2 27 28 1/2 30 33 37 1/2 39 40 1/2 40 1/2 6 3/4 x X 6 3/4 6 3/4 X 6 3/4 X 6 3/4 6 3/4 x x 6 3/4 X 6 3/4 x 6 3/4 x 63/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 x 6 3/4 X 6 3/4 6 3/4 6 3/4 X x x 6 3/4 X 6 3/4 x 6 3/4 X 6 3/4 x Table Specifications: These sizes are for dry service condition of use. Reverse use of this table to convert from glued laminated timber sizes to steel sections is non-conservative in all cases and is NOT PERMITTED. Smaller glued laminated timber sizes may be possible with engineering calculations based on actual span and loading conditions. Glued laminated timber beam sizes are based on a span to depth (L/d) ratio of 21. When the span to depth ratio is larger, sizes should be determined by engineering calculations. To determine glued laminated timber beam sizes, Fox was adjusted by the volume factor. It is assumed that all beams are adequately braced for lateral stability. Tabulated beam sizes have been checked for adequacy in flexure and deflection. It is the responsibility of the designer to check for adequacy in shear. A minimum glued laminated timber depth of 6 inches is used in this table. Standard glued laminated timber sizes are used in this table. While these design conversions have been prepared in accordance with recognized engineering principles and are based on accurate technical data, conversions should not be used without competent examination and verification of the accuracy, suitability, and applicability by a qualified design professional. AITC MAKES NO REPRESENTATION OR WARRANTY, EXPRESSED OR IMPLIED, THAT THE INFORMATION CONTAINED HEREIN IS SUITABLE FOR ANY GENERAL OR SPECIFIC USE OR IS FREE FROM INFRINGEMENT OF ANY PATENT OR COPYRIGHT. ANY USER OF THIS INFORMATION ASSUMES ALL RISK AND LIABILITY ARISING FROM SUCH USE. 9 10 1/2 12 15 15 16 1/2 16 1/2 16 1/2 18 19 1/2 21 21 21 22 1/2 24 24 27 28 1/2 33 34 1/2 34 1/2 36 40 1/2 Background Information The table included with this exam converts A572 Grade 50 steel beam sections to Western Species glulam member sizes from the 24F-1.8E stress class. In the 9th edition Steel Manual, the ASD available flexural strength of steel beams was M' = (0.66F,)S where F, 50 ksi for A572 steel and S is the section modulus. For example, a W6x9 has section modulus S-5.56 in³, making its ASD available flexural strength M'-0.66(50 ksi) (5.56 in³) 184 kip-in-15.3 kip-ft. The glulam sizes that can be substituted for each steel W-section are listed for use in floor systems (CD=1.0), roof systems with snow loads (CD=1.15), and roof systems with non- snow (construction) loads (CD-1.25). For example, in a floor system with Cp-1.0, any of the following glulams from the 24F-1.8E stress class can be substituted for a W6x9 . 3 1/8 x 13 1/2 (6-3.125 inch, d=13.5 inch) • 5 1/8 x 10 1/2 (b-5.125 inch, d-10.5 inch) .6 3/4 x 9 (b-6.75 inch, d-9.0 inch) In other words, these glulams have the same or greater available flexural strength compared to the W6x9. Make note of the following from the Table Specifications: • The glulam sizes are based on dry service conditions, CM = 1. Although not stated, normal temperatures (C-1) also apply. • The glulam sizes are based on adequate bracing for lateral stability (C₁=1). • The glulam sizes are based on adjusting the design bending stress, For by the volume factor, Cy. • In computing the volume factor, a span to depth ratio, L/d 21 is assumed for all glulams in the table. For example, for a 6 3/4 x 15 glulam, the span length used in computing its volume factor is L-21d-21(15 inch)-315 inch 26.25 ft. The table assumes all members are loaded on their narrow face (Cfu-1), bent about their strong axis. The members are neither curved nor tapered (Ce and C, both equal 1). Ulti- mately, the only adjustment factors that apply in computing the glulam sizes in this table are Cy and CD F = FbxCpCv Cy is the computed volume factdor and Cp is specified in the table. Calculate the adjusted bending strength of the equivalent glulam. Use Cp=1. F psi ba Calculate the ASD available flexural strength of the equivalent glulam. M' kip-ft Calculate the ASD available shear strength of the equivalent glulam. Assume Cur-1. V' = kip Calculate the required bearing area for a concentrated load of P-20 kip applied per- pendicular to the wide face of the lams. Assume Co=1. A₁ > in²

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