BOUNDARY LAYERS IN WEDGES OF LAMINATED COMPOSITE STRIPS UNDER GENERALIZED PLANE DEFORMATION-PART

Based upon Lekhnitskii's formulation and the Stroh formalism, the structure of the asymptotic solutions has been examined for the boundary layer on the wedge type cross section of a laminated composite strip. The composite strip is assumed under the so-called generalized plane deformation, which includes tension, bending and/or torsion by the terminal tractions as well as the generalized plane strain problem. The solution structures are obtained, with the aid of numerical calculation, for various kinds of wedge geometry including the free edge and the delamination cracks with the crack faces opened or closed. Finally the nature of the asymptotic solutions is discussed, including the mode mixity of singular stress field ahead of the wedge tip, it is found that for a free edge problem the mode mixity of the singular asymptotic traction vector on the interfacial plane near the free edge remains invariant under varying types of remote loadings once a pair of adjacent materials (or ply orientations) is given and that accordingly one single scaling parameter governs the near field response.

[1]  Henryk K Stolarski,et al.  On the significance of the logarithmic term in the free edge stress singularity of composite laminates , 1989 .

[2]  S. G. Lekhnit︠s︡kiĭ.  Theory of elasticity of an anisotropic body , 1981 .

[3]  T. C. T. Ting,et al.  Explicit solution and invariance of the singularities at an interface crack in anisotropic composites , 1986 .

[4]  Z. Zhao,et al.  Determining the SIF of a V-notch from the results of a mixed-mode crack , 1992 .

[5]  S. Im.  Delamination Cracks Originating form Transverse Cracking in Cross-Ply Laminates under Various Loadings , 1991 .

[6]  J. D. Eshelby,et al.  Anisotropic elasticity with applications to dislocation theory , 1953 .

[7]  A. N. Stroh.  Steady State Problems in Anisotropic Elasticity , 1962 .

[8]  R. L. Spilker,et al.  On the Logarithmic Singularity of Free-Edge Stress in Laminated Composites Under Uniform Extension , 1982 .

[9]  T. C. T. Ting,et al.  Edge singularities in anisotropic composites , 1981 .

[10]  John D. Whitcomb.  Three-Dimensional Analysis of a Postbuckled Embedded Delamination , 1989 .

[11]  G. Dantzig,et al.  Mathematics of the decision sciences , 1968 .

[12]  Hyung-Kyu Kim,et al.  Delamination crack originating from transverse cracking in cross-ply composite laminates under extension , 1991 .

[13]  Zhigang Suo,et al.  Singularities, interfaces and cracks in dissimilar anisotropic media , 1990, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[14]  Kim Yujun,et al.  Delamination cracks originating from transverse cracking in cross-ply laminates under various loadings , 1993 .

[15]  K. Washizu.  Variational Methods in Elasticity and Plasticity , 1982 .

[16]  S. Im,et al.  Boundary layers in wedges of laminated composite strips under generalized plane deformation—Part I: Asymptotic solutions , 1995 .

[17]  Su-Su Wang.  EDGE DELAMINATION IN ANGLE-PLY COMPOSITE LAMINATES , 1981 .

[18]  Fuh-Gwo Yuan,et al.  A Hybrid Finite Element Approach to Composite Laminate Elasticity Problems With Singularities , 1983 .

[19]  James R. Rice,et al.  Elastic Fracture Mechanics Concepts for Interfacial Cracks , 1988 .