Mechanics of Materials CIVL 3322 / MECH 3322 Shear Stress in Beams II 7 November, 1940 – Four months after the bridge's completion, the middle section of the Tacoma Narrows Bridge across the Tacoma Narrows in state of Washington collapsed in a windstorm. Shear Stress in Beams II 2
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Mechanics of Materials - University of Memphis Stress in Beams II.… · 14 January 2011 1 Mechanics of Materials CIVL 3322 / MECH 3322 Shear Stress in Beams II 7 November, 1940 –
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Mechanics of Materials CIVL 3322 / MECH 3322 Shear Stress in Beams II
7 November, 1940 – Four months after the bridge's completion, the middle section of the Tacoma Narrows Bridge across the Tacoma Narrows in state of Washington collapsed in a windstorm.
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Fx∑ = MIzA '∫ ydA '− M + ΔM
IzA '∫ ydA '+ FH = 0
− ΔMIzA '∫ ydA '+ FH = 0
FH = ΔMIzA '∫ ydA '
Q = ydA 'A '∫
FH = ΔMQIz
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τ = VQIzt
t = width of the section at some depth in the beam
Q= yiAii∑
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9.9 A 1.6-m long cantilever beam supports a concentrated load of 7.2 kN, as shown below. The beam is made of a rectangular timber having a width of 120 mm and a depth of 280 mm. Calculate the maximum horizontal shear stresses at points located 35 mm, 70 mm, 105 mm, and 140 mm below the top surface of the beam. From these results, plot a graph showing the distribution of shear stresses from top to bottom of the beam.