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Stiffness Matrix

  1. Oct 6, 2007 #1
    I spent almost 2 days to solve the following stiffness matrix

    [tex]\left(\begin{array}{c}f1\\f2\\f3\\f4\\f5\end{arr ay}\right)=\left(\begin{array}{ccccc}20&-20&0&0&0\\-20&40&-20&0&0\\0&-20&40&-20&0\\0&0&-20&40&-20\\0&0&0&-20&20\end{array}\right)\left(\begin{array}{c}0\\d2\\d3\\d4\\0\end{arr ay}\right)?[/tex]

    I have tried to partition the matrix like the following





    but still cannot solve for the equation.

    The partitioned matrix produced UNDETERMINED Multiplication and Addition of 2 matrices.

    Can anyone help me on this, please...
  2. jcsd
  3. Oct 6, 2007 #2


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    Homework Helper

    What exactly are you trying to obtain? Are you trying to find the d-s?
  4. Oct 6, 2007 #3
    All of forces fx and displacements dx magnitude. Please look at my attached image for the system. Note that the magnitude of f3 = 10 kN/m and the displacement of node 1 and 5 is 0 also the magnitude of k1 is = k2 = k3 = k4 = 20 kN/m.

    Attached Files:

    Last edited: Oct 6, 2007
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