Shear stress versus shear strain

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Shear stress versus shear strain
For homogeneous isotropic materials pure shear
causes angular distortion of a material as shown
above. Pure shear is most often studied by
torsional tests of thin bars. Behavior is
completely analogous to normal stresses.
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Shear stress-strain diagram
G is shear modulus or modulus of rigidity
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• The shear stress-strain diagram for a titanium
  alloy bar tested in torsion is shown in the
  Figure. Determine
• Shear modulus
• Proportional Limit
• Ultimate stress
• Yield stress
• Fracture stress

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A bearing pad used to support machines is shown.
The following formulae can be used to determine
shear stress, shear strain and displacement.
For small angles
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Problem (4) The plastic block shown of 50 mm
depth is bonded to a rigid support and to a
vertical plate to which a 240-kN load P is
applied. Knowing that for the plastic used
G1000 MPa, determine the deflection of the
plate.
Rigid support
Spring 2006 Mid Term Question
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Problem (4) The plastic block shown of 50 mm
depth is bonded to a rigid support and to a
vertical plate to which a 240-kN load P is
applied. Knowing that for the plastic used
G1000 MPa, determine the deflection of the
plate.
Rigid support
Spring 2006 Mid Term Question
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Allowable Stress
Factor of safety
F.S.1
F.S.3
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Designing for allowable stress
Bearing (compression)
Tension
Shear
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Problem (6) Determine the intensity w of the
maximum distributed load that can be supported by
the hanger assembly so that an allowable shear
stress of ?allow 15 ksi is not exceeded in the
0.40-in.-diameter bolts at A and B, and an
allowable tensile stress of sallow 25 ksi is
not exceeded in the 0.5-in.-diameter rod AB.
Spring 2006 Mid Term Question
Solve at home will cover in help session on
Sept 7th