Dynamic growth of an internal circular crack in a transversely isotropic composite

Abstract

The dynamic growth of an internal circular crack in a transversely isotropic composite is investigated using the techniques of Hankel and Laplace transforms. The Laplace inversion is carried out through a complete contour integration. For the crack running at a constant speed, exact dynamic solutions for crack shape and stress distribution with singularities in the crack plane are obtained in closed forms in terms of anisotropic material constants and crack speed. Graphite/epoxy and E glass/epoxy materials and an isotropic material are used as example materials in calculating the numerical values of the dynamic stress intensity factor and crack shape. The dynamic solution reduces to the static solution at zero crack speed and deviates at speeds other than zero. Deviation between dynamic and static solutions is governed by dynamic correction factors, which are non-dimensional functions of anisotropic material constant ratios and the ratio between crack speed and shear-wave speed. Values of these dynamic factors are obtained for the sample composites for a large range of crack speed. © 2001 Elsevier Science Ltd. All rights reserved.