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Need fast help!, (solid mechanics)

  1. May 10, 2005 #1
    Hi. We are doing a project in school with FEM calculation, and i am off to validate the tensions in the construction, but i do not know how i get the tension in the construction by hand calculation seen it is statically indeterminate, and it isn’t a truss.

    My question is how can I calculate the tension for the beams?, (what method do I have to use)

    What is the diffrent's from a truss construction in a solid mechanics point of view?

    Last edited: May 10, 2005
  2. jcsd
  3. May 10, 2005 #2


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    It seems to me the typical problem to divide the structure into a symmetric part and another asymmetric part, and solving cutting the structure by the symmetry axis. Are you familiar with this method?
  4. May 10, 2005 #3
    Thx;l i have read about it, i will think about it, if you can plz answer the outer questions.

    Kindly Paul-M
  5. May 10, 2005 #4


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    Could you rephrase your question? It doesn't make a whole lot of sense as to what you are asking.

    Have you looked at the method of sections for trusses?
  6. May 10, 2005 #5
    It isn't a truss, my problem is that i need more then the 3 equilibrium equations.
  7. May 11, 2005 #6


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    I have looked for the translation of "truss" in spanish, but sure you would laugh at it if I tell you what that means in spanish.

    Sure your structure is hyperstatic. You only have 3 equations for static equilibrium, and 6 unknown forces on each support.

    When one finds this kind of situations, you must write additional equations for Compatibility of Movements of the supported extremes. For instance you know that the left bottom support cannot neither rotate, neither go upwards, nor go downwards. These three conditions give you the three additional equations you need. Another method of resolution would be therefore to release the left support (leaving it being suspended in air) and so your structure will be Isostatic. In particular, you will have three unknown forces acting on this support (one vertical, another horizontal and a bending moment).
  8. Oct 9, 2009 #7
    hiiii its me peer....i need some help to solve dis problem.
    A thin plate containing a central hole is made of an elastic and perfectly plastic material with youngs modulus E=200GN/M,Poissons ratio v= 0.3 and yield strength infinity=100MPA, D=0.4M,L=2M,W=1.2M.THE THICKNESS OF PLATE IS 0.01

    A. find the applied remote stress (infinity) that leads to the initial yielding of any where in the plate.show the distribution of von mises and deformation of the plate at this applied stress.
    B.find the maximum possible stress (infinity) that the plate can carry before full plastic collapse.show the distribution of von mises stress and deformation of the plate immediately before this applied stress is reached.
  9. Oct 9, 2009 #8
    any 1 please reply me soon as possible
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