Fracture of Composite Materials: Proceedings of the Second USA-USSR Symposium, held at Lehigh University, Bethlehem, Pennsylvania USA March 9–12, 1981

The Second USA-USSR Symposium on Fna~e 06 Compo~~e Mat~a£h took place at Lehigh University, Bethlehem, Pennsylvania, during 9-12 March, 1981. This bilateral program between the U. S. and Soviet Union was organized by Professor George C. Sih of the Institute of Fracture and Solid Mechanics at Lehigh Uni­ versity and Dr. Vitauts P. Tamuzs of the Institute of Polymer Mechanics of the Academy of Sciences of the Latvian SSR in Riga. The First Symposium was held in 1978 at Jurmala near the coast of Riga Bay. The primary reasons for initiating this series of Symposia were to dissemi­ nate present knowledge, to promote interchange of ideas, and to stimulate addi­ tional studies on the development of composite materials between the U. S. and USSR. Both countries have a vested interest in developing the capability to assess and utilize the attractive mechanical properties of composites so that they can be tailor-made to meet specific design requirements. Despite the in­ creasing number of published papers and articles, there is no communication more effective than on a person-to-person basis. It is with this objective in mind that a small group of engineers and scientists from the U. S. and USSR have planned to meet every two years to report recent progress on composite material research. The size of this group is approximately sixty (60) participants. The presentation involves about forty (40) technical papers which are published in volume.

Table of Contents:
Section I Analytical Modeling.- Stochastic models of fracture of unidirectional fiber composites.- Tight bounds for the probability distribution of the strength of composites.- Two approaches in fracture mechanics of composites.- Computer simulation of various fracture mechanisms in fibrous composite materials.- Application of the cubic strength criterion to the failure analysis of composite laminates.- Application of impulse functions to the reliability of fiber reinforced composites.- Section II Crack and Fracture Analysis.- Transient hygrothermal and mechanical stress intensities around cracks.- Strength evaluation of composites with sharp-pointed inclusions.- Local fracture in fibrous media.- Surface notches in composites.- Section III Micromechanics.- Some peculiarities of fracture in heterogeneous materials.- Physical principles of prediction of heterogeneous material fracture.- Microscopic mechanisms of fiber composite deformation and fracture.- Analysis of microfracture in composite.- Section IV Unidirectional Composites.- Fracture of unidirectional composite materials under the axial compression.- Influence of stress interaction on the behavior of off-axis unidirectional composites.- Characterization of matrix/interface-controlled strength of unidirectional composites.- Determination of fracture toughness of unidirectionally fiber-reinforced composites.- On failure modes of unidirectional composites under compressive loading.- Section V Laminates.- Delamination of T300/5208 graphite/epoxy laminates.- Stress singularities in laminated composites.- The relationship of stiffness changes in composite laminates to fracture-related damage mechanisms.- Three dimensional finite element analysis of damage accumulation in composite laminate.- Post-crazing analysis of glass-epoxy laminates.- Section VI Stress and Strength Analysis.- Generalized structural strength criteria of reinforced plastics under plane stress.- Non-linear phenomenological models of fibre-reinforced composites.- The effect of interface structure on the strength of fibrous composite materials.- An estimation of the compressive strength of a fibrous composite.- Equation of state for reinforced plastic materials subjected to mechanical and thermal loading with the account taken of damage and physical-chemical transformations.- Strength of layered composite cylindrical shells under dynamic loading.- Section VII Experiments and Tests.- Damageability evaluation of organic and carbon fiber plastics by non-destructive technique.- Mechanical luminescence study of composite fracture in a plane-stressed state.- Comparative evaluation of shear test methods for composites.- Experimental determination of flaw shapes and stress intensity distributions; conditions for application to composite materials.- Peculiarities of the fracture of dry and wet compact bone tissue.- Flaws and defects of structural carbon fibers.- Fatigue crack propagation of sheet molding compounds in various environments.- List of Participants.