Course Title: Strength of Materials (CVE 202)

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Course Title Strength of Materials
(CVE 202)

• Course Lecturer Engr. F. M. Alayaki
• Civil Engineering Department, College of
  Engineering,University of Agriculture
  Abeokuta,Nigeria
• Course Unit 2Contact Time 2 HoursLaboratory
  Time 1 Hour

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Course Content

• Direct Stress Hookes experiment. Axially
  loaded bar, Tensile and compressive stresses.
  Strain tensile and compressive strains.
  Stress-stain curves for ductile and brittle
  materials. Modulus of elasticity. Mechanical
  properties of materials elastic limits,
  proportional limit, yield points, ultimate
  strength. Modulus of toughness. Percentage
  reduction in areas. Percentage elongation.

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• Principal stress Definition, deductions from
  Mohrs circle. Mohrs circle method of
  determining stress and strain. Working stress,
  proof stress, Poissons ratio, modulus of
  rigidity. Factors of safety. Lateral stresses
  and strains. Bars of varying cross sections
  compound bars under stress and strain.
  Temperature stresses.

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• Torsion effects of torsion. Twisting moment.
  Polar second moments of area. Torsional shearing
  stresses and strain. Modulus of elasticity in
  shear. Angle of twist. Rupture.
• Shearing force and bending moments Simply
  supported beam. Loading forces and moments in
  beams. Shear and moment equations. Shear force
  and bending moment diagrams.

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Typical Questions

• 1. The following data were recorded during a
  tensile steel test
• Diameter of bar 20mm
• Distance between gauge points 200mm
• Elongation due to load of 50KN 0.18
• Load at yield point 79KN
• Failing or ultimate load 127KN
• Calculate in N/mm2
• the stress at yield point, (b) the ultimate
  stress, (c) the modulus of elasticity of the
  steel
• 2. ( a ) Define the following terms
• Component of Forces
• Resultant
• Equilibrant
  
• Moment of Forces
• Centroid of a Body
• ( b ) i Define the terms shear force and
  bending moment.
• ii What do you understand by the term point of
  contraflexure?
•  
•  

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• ( c ) Using simple sketches show the
  following types of beams
• Simply supported beam with a point load.
• Simply supported beam with Uniformly Distributed
  Load (UDL).
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• 3. Three separate members of steel, copper and
  brass are of identical dimensions and are equally
  loaded. Youngs moduli for the materials are
  steel, 210,000N/mm2 copper, 100,000N/mm2 brass,
  95,000N/mm2. If the steel member stretches
  0.13mm, calculate the amount of elongation in the
  copper and brass members.
• 4. (a) Define the terms shear force and bending
  moment.
• (b) What do you understand by the term point of
  contraflexure?
• (c) Using simple sketches show the following
  types of beams
• Simply supported beam with a point load.
• Simply supported beam with Uniformly
  Distributed Load (UDL).
• Overhanging beam with UDL.
• Cantilever beam with point load at its end.
• Simply supported beam with uniformly varying
  load.
•  

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• 5. A cantilever beam AB 1.5m long is loaded with
  a UDL of 2 KN/m and a point load of 3KN as shown
  in fig. 1. Draw the shear force and bending
  moment diagram for the cantilever beam. Indicate
  the positions and values of the following.
• Point of zero shear force.
• Maximum shear force.
• Maximum bending moment.
•  
• 6 (a) Derive from first principle the formula for
  the moment of inertia of a rectangular section.
• (b) Determine the moment of inertia Ixx of the
  section shown in fig. 2.
•  
• 7. Define stress, strain, and elasticity. Derive
  a relation between stress and strain of an
  elastic body.
•  
• 8. Two wires, one of steel and the other of
  copper, are of the same length and are subjected
  to the same tension. If the diameter of the
  copper wire is 2mm, find the diameter of the
  steel wire, if they are elongated by the same
  amount. Take E for steel as 200 x 103 N/mm2 and
  that for copper as 100 x 103 N/mm2.

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• 
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  KN 2KN/m A B
  0.25m 1.00m 0.25m
  Fig. 1
  24mm
  24mm 300mm
  Fig. 2 200mm