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9.8: Why bother if they are the same?

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    K is useful because stress intensity factors, like stresses, are additive. Irwin showed that any loading state could be broken down into 3 different types of loading that he called modes, I, II and III:

    Diagram of 3 different types of loading

    To get the total K, we just sum the contribution from each of the three modes.

    This is much more difficult to do with energies, where we would have to think about interaction terms.


    This page titled 9.8: Why bother if they are the same? is shared under a CC BY-NC-SA 2.0 license and was authored, remixed, and/or curated by Dissemination of IT for the Promotion of Materials Science (DoITPoMS) via source content that was edited to the style and standards of the LibreTexts platform.

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