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Statically Indeterminate Problem

  1. Jan 23, 2005 #1
    Before you start going through equations and trying to solve this I just need a simple question answered about this problem.

    1) Is it correct for me to assume that the pressure on both walls is equal?

    If so, I think the normal stress of the aluminum and steel bars are equal.


    A circular bar consist of 3in diameter aluminum alloy with Young’s modulus, E = 10,600 ksi, poisson ratio, ν = 0.33, and temperature coefficient, α = 12.5 * 10-6 /°F and 4in diameter steel with Young’s modulus, E = 30,000 ksi, poisson ratio, ν = 0.3, and temperature coefficient, α = 6.6 * 10-6 /°F separated by a rigid piece as shown. The bar is fixed between two rigid end supports and is considered unstressed at 0°F. Determine (a) the normal stress in both the aluminum bar and the steel bar, and (b) the change in diameter of the aluminum and steel bar.

    Last edited by a moderator: Apr 21, 2017
  2. jcsd
  3. Jan 24, 2005 #2


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    Since the stresses are inversely proportional to area and Young's, the two members will not have the same stresses.
  4. Jan 24, 2005 #3
    Thank you.
  5. Jan 25, 2005 #4


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    The force is the same through the entire section, but not the pressure.
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