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Can strain exist without deflection?

  1. Jan 10, 2015 #1
    Lets take an example of a person pushing a thick wall, of course no deflection in the line of action of force is seen but can strains be induced in it, like surface slips?
  2. jcsd
  3. Jan 10, 2015 #2

    Doug Huffman

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    Gold Member

    The definition of strain is dL/L. Stress less than some limit should cause no strain.
  4. Jan 10, 2015 #3
    What are surface slips?

  5. Jan 10, 2015 #4
    This is not correct. Any stress will cause a strain. But, if the stress is very low, the strain might not be significant.

  6. Jan 10, 2015 #5
    via wikiapedia: http://en.wikipedia.org/wiki/Deflection_(engineering), http://en.wikipedia.org/wiki/Deformation_(mechanics),

    I believe you can have a displacement at the line of action even in a thick wall. Unless there is some sort of rigid constraint that prevents that.

    deflection is the degree to which a structural element is displaced under a load. It may refer to an angle or a distance.

    strain is a normalized measure of deformation representing the displacement between particles in the body relative to a reference length.

    So, I think it depends on the constraints. Otherwise there will be a strain under any deflection, no matter how small. Check out my picture it may help.

    Attached Files:

  7. Jan 11, 2015 #6
    strain will be induced due to its own weight also.So,strain will always be present.
  8. Jan 11, 2015 #7
    Hi chet, thanks for the reply

    Surface slips by which i mean the deformation of the slip planes at the surface if the force is just enough.
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