Page 138 - Mechanics Analysis Composite Materials
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Chapter 4. Mechanics of a composite layer 123
Fig. 4.4. Filament wound composite pressure vessel with a polyethylene liner. Courtesy of CRISM.
Fig. 4.5. An isotropic layer.
where E is the modulus of elasticity, v the Poisson’s ratio, and G is the shear
modulus that can be expressed in terms of E and v with Eq. (2.57). Adding
Eqs. (4.1) for normal strains, we get
1
Eo =-Go ,
K
where
is the volume deformation. For small strains, volume dq of an infinitesimal
material element after the deformation can be found knowing volume d V before
the deformation and & as
Volume deformation is linked with the mean stress
