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Homework Help: Number of joints

  1. Aug 1, 2016 #1
    1. The problem statement, all variables and given/known data
    in the notes, r =number of reactions, m = number of truss members , j = number of joints
    i suspect that the j for d and e are wrong...
    2. Relevant equations

    3. The attempt at a solution
    I have circled the joints and calculated them, for d , j= 9,
    for part e , it should be j= 14,
    Am I right?

    Attached Files:

    • 330.jpg
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  2. jcsd
  3. Aug 1, 2016 #2


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    The x braces might or might not be connected where they cross, although usually connecting them helps out of plane bucking for compression members. Either way, the brace forces are the same, so you need not count those joints when determining degree of indeterminacy. The author didn't pick a good example in my opinion.
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