Analysis of sandwich construction

Discussion in 'Materials' started by arekisir, Mar 28, 2016.

  1. arekisir
    Joined: Jul 2010
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    arekisir Junior Member

    Greetings,

    Looking for some pointers on analysis of sandwich composite.

    I want to understand if the core will shear or skin will fail in compression or tension given a set construction.

    Is software or analysis techniques available that can build up a sandwich and apply a uniform load on surface?

    As an example sandwich (compression load applied to woven carbon surface)
    -300g biax carbon
    -10mm 80kg pvc foam
    -200g 0/90 woven carbon

    Thanks in advance
    Alex
     
  2. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Maker's specs re compression and shear strength no use to you ? If you are using expensive, exotic laminates, might it be worth going to a denser grade of foam ?
     
  3. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Is this a flat panel?
     
  4. arekisir
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    arekisir Junior Member

    Some flat some curved, would be general hull construction over which curvature would vary
     
  5. gonzo
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    gonzo Senior Member

    The most accurate analysis technique is to test panels to destruction. The main advantage is that since you will supply the panels, they will be the same as the ones in the boat.
     

  6. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    It is clear that if subjected to a test "to destruction", the OP will not have doubts about his set : it is destroyed. Is that why you needed to know if it was a flat panel?
    I think what arekisir is asking for is an empirical procedure which allows him "to understand if the core will shear or skin will fail in compression or strain given a set construction" : a calculation method that lets he know the stresses to which it is subjected and the maximum load that should withstand.
    There are several studies on how to calculate composite materials. A panel of a ship's hull is subjected precisely to a design pressure which it is assumed uniform and perpendicular to the panel. The study of the layers of that panel allows to know tension/compression each layer supports as well as shear force on the core.
    For example, in standard ISO 12215-5 are given, for small craft, design pressures and all the other procedures for that study.
     
    Last edited: Mar 31, 2016
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