1 12 10 3 2 1 12 3 4 45 2 2833 in 4 ignore 3 term 2 1 3 089 3 311 3 1 3 10 3

# 1 12 10 3 2 1 12 3 4 45 2 2833 in 4 ignore 3 term 2 1

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? = 1 12 (𝑡)10 3 + 2 ( 1 12 𝑡 3 (4) + (𝑡)(4)(5) 2 ) = 283.3 𝑡 in 4 (ignore 𝑡 3 term) ? ? = 2 ( 1 3 ) (𝑡(0.89) 3 + 𝑡(3.11) 3 ) + 1 3 (10)𝑡 3 + 0.89 2 (10)(𝑡) = 28.5 𝑡 in 4 (ignore 𝑡 3 term) J = I x + I y = (283.3 + 28.5) t = 311.8 t in 4 . For the weld configuration as shown, we have 𝑓 = ? ? 𝑣 ? = (25)(11.11)(5) 311.8(𝑡) = 4.45 kips/in ( 1 𝑡 in ) 𝑓 ? = ? ? ? = (25)(11.11)(3.11) 311.8(𝑡) = 2.77 kips/in ( 1 𝑡 in ) 𝑓 ?ℎ??? = 𝑃 ? 𝐴 = 25 18(𝑡) = 1.39 kips/in ( 1 𝑡 in ) 𝑓 ????𝑙???? = √(𝑓 ? + 𝑓 ?ℎ??? ) 2 + 𝑓 2 = √(2.77 + 1.39) 2 + (4.45) 2 ( 1 𝑡 in ) = 6.09 kips/in ( 1 𝑡 in ) Capacity of E70 fillet weld : φF w =0.75(0.6)( F EXX )= 0.75(0.6)(70) ksi Effective throat : t = 0.707 leg Therefore, we have (𝑓 ????𝑙???? ≤ 𝜑𝐹 ? ) 6.09 ( 1 0.707 leg ) ≤ 0.75(0.6)(70) ⇒ leg ≥ 0.273 in Use 5/16-in. weld. Note: In this example, angle θ for the weld configuration varies and is difficult to determine. The calculations assume θ = 0 deg when determining weld strength capacity.
78 Mc/I Mc/I (3/2) ( V/A w ) Vertical weld Bending stress (Not used in calculation) Shearing stress c Example : Determine fillet weld size for the connection. Use E70 electrodes and assume SMAW process. Assume member thicknesses do not control. P u = 45 kips; e =2-1/2 in; L w =8in. Solution : Weld strength : φR nw = φF w t e A w = 0.75(0.6 F EXX ) t e A w =0.75(0.6 F EXX )0.707(leg)( L w ) Assume weld throat size = t in 𝑓 ? = 𝑃 ? 𝐴 ? = 45 (2)(8)(𝑡) = 2.81 kips/in ( 1 𝑡 in ) 𝑓 ? = ?? ? = (45)(2.5)(4) 1 12 (8) 3 (𝑡)(2) = 5.27 kips/in ( 1 𝑡 in ) 𝑓 ????𝑙???? = √(2.81) 2 + (5.27) 2 ( 1 ? in ) = 5.97 kips/in ( 1 ? in ) Capacity of E70 fillet weld : φF w =0.75(0.6)(70) ksi Effective weld size t = 0.707 leg, Therefore, we have (𝑓 ????𝑙???? ≤ 𝜑𝐹 ? ) 5.97 ( 1 0.707 leg ) ≤ 0.75 (0.6 𝐹 𝐸𝑋𝑋 )(1 in weld) = 0.75(0.6)(70)(1) ⇒ leg ≥ 0.268 in Use 5/16- in weld. P u =45 kips 8 in 8 in P u P u 2-½ in

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• Spring '14
• GregoryG.Deierlein
• Shear Stress, Strength of materials, Arc welding, Weld, Shear strength