ENGR 220 Section 7'4

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ENGR 220Section 7.4
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Shear Flow in Built-up Members
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Shear Flow along Longitudinal direction of the
joint
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Shear Flow, q

• The measure of force per unit length along a
  longitudinal axis of a beam

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Lecture Example The beam is made from two
boards fastened together with nails spaced every
2 in. If the internal shear force of V 150 lb
is applied to the boards, determine the shear
force resisted by each nail.
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Lecture Example Determine the maximum shear V
that the beam can sustain if the allowable shear
stress for the wood is 400 psi. What is the
required spacing of the nails if each can resist
a shear force of 400 lb.
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Lecture Example The box beam is constructed
from four boards that are fastened together using
nails spaced along the beam every 2 in. If a
force P 2 kip is applied to the beam, determine
the shear force resisted by each nail at A and B.