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Engineering LibreTexts

5.3: Determinacy and Stability of Trusses

  • Page ID
    42963
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    The conditions of determinacy, indeterminacy, and instability of trusses can be stated as follows: \[\begin{array}{l}
    m+r<2 j \quad \text { structure is statically unstable } \\
    m+r=2 j \quad \text { structure is determinate } \\
    m+r>2 j \quad \text { structure is indeterminate }
    \end{array}\]

    where

    \(m =\) number of members.

    \(r =\) number of support reactions.

    \(j =\) number of joints.


    This page titled 5.3: Determinacy and Stability of Trusses is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by René Alderliesten (TU Delft Open) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.