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Homework Help: Need Verification: Combined Loads Finding Stress

  1. Nov 16, 2008 #1
    1. The problem statement, all variables and given/known data

    I think I've solved this properly, but if you guys wouldn't mind verifying my work and pointing out any errors (if there are any), it would be much appreciated.

    http://img391.imageshack.us/img391/6520/problemvm0.jpg [Broken]

    I've already calculated the equivalent force-couple system at the plane of the elemental stress block, which is shown above. That's completely right, I know of it :). Now, I need to solve for the components of normal and shearing stress associated with that elemental stress block.

    2. Relevant equations

    [tex]\sigma[/tex]Axial = P / A
    [tex]\sigma[/tex]Bending = Mc / I
    [tex]\tau[/tex]Shear = VQ / IT
    [tex]\tau[/tex]Torque = Tc / J

    We already are given:
    A = 12.57 in^2
    J = 25.13 in^4
    I = 12.57 in^2
    Q = 5.33 in^3
    D = 4 in

    3. The attempt at a solution

    Using the equations above, I've calculated:

    [tex]\sigma[/tex]Axial = 477.46 psi
    [tex]\sigma[/tex]Bending = 12,414.09 psi
    [tex]\tau[/tex]Shear = 106.10 psi
    [tex]\tau[/tex]Torque = 5729.58 psi

    Did this all with excel :).

    Do those answers sound right? The next step which I am having difficulty with is calculating the [tex]\sigma[/tex]X, [tex]\sigma[/tex]Y, and [tex]\tau[/tex]XY. I understand that I'm just using super position for this, but I'm not sure whether to add or subtract the two.

    Thanks!
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
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