3/18/2002, Monday Energy Approach to Fracture

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3/18/2002, MondayEnergy Approach to Fracture
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Double Cantilever Beam (DCB)
W is the strain energy of DCB
If the crack extends by an amount da, the
necessary additional surface energy is obtained
from the work done by the external body forces
Pdu and the release of strain energy dW.
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Body Stiffness M
Crack extension would result in a decrease of
plate stiffness
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Energy Release Rate
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Force Deflection Relation
From Mechanics of Materials, Elementary simple
beam problem,
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Fixed Loading
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Fixed Grip
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Energy Release Rate
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J-Integral
Reversibility of stress-strain relationship
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Path Independent
For a closed contour
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Crack Tip Mesh