1970 Volume 19 Issue 206 Pages 974-980
The fracture strength of helical-wound composite cylinder under axial tension is discussed. The three-dimensional elastic stress components on the planes which do not intersect the fibers are analysed by use of the in-plane stress components in each layer. Then, in order to determine the tensile strength, they are related to the three kinds of fundamental strength of unidirectional fiber-reinforced composites obtained experimentally.
The axial tension tests are carried out on glass-epoxy cylindrical composites which are helically wound at various sorts of winding angle. The experimental results on fracture strength including elastic moduli are found to be in good agreement with the analytical results which take into account the yielding of matrix before fracture.
Based on the similar concept discussed here, the fracture strength under torsion and internal pressure can also be analysed showing good agreements with experimental results and they will be reported in the forthcoming papers.