Journal Published Online: 01 July 1979
Volume 1, Issue 4

Simple Torsion Test for Determining the Shear Moduli of Orthotropic Composites



The shear properties of a composite must be known for the design and use of the composite material. Although many methods are available for measuring in-plane shear, no simple test technique has been offered for determining out-of-plane shear. We, however, have developed a simple method for determining both in-plane and out-of-plane shear moduli of a homogeneous, orthotropic material. From torsion tests performed on specimens in the shape of a rectangular parallelepiped (a prism whose bases are parallelograms) of at least two different cross sections, the effective in-plane (G13) and out-of-plane (G23) moduli (Fig. 1) can be determined. (Please note that fiber direction is three-directional.) Additionally, we have determined these moduli for two different graphite-epoxy composites (AS/3501 and T300/5209), composites that have both uniaxial and cross-ply fiber orientations.

Author Information

Theodore Sumsion, H
Rajapakse, YDS
Pages: 4
Price: $25.00
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Stock #: CTR10683J
ISSN: 0884-6804
DOI: 10.1520/CTR10683J