Size Effect on Fracture of Composite and Sandwich Structures

  • Emmanuel E. Gdoutos
  • Zdenĕk P. Bažant


The objective of this article is to review the work performed on the scaling and size effect in the failure of composites, foams and laminate—foam sandwiches. These materials exhibit quasibrittle behavior which is characterized by a fracture process zone that is not negligible compared to the characteristic size of the structure. The mean size effect is found to be essentially deterministic, caused by energy release due to stress redistribution. The chapter consists of six sections:After introduction, the second section deals with the size effect on the nominal strength of notched specimens of fiber composite laminates under tension. In the third section, the size effect of fiber—composite laminates on flexural strength is studied. The fourth section studies the effect of structure size on the nominal strength of fiber—polymer composites failing by propagation of a kink band with fiber microbuckling. The fifth section deals with the size effect of fracture of closed-cell polymeric foams. The sixth section analyzes the size effect on the compressive strength of sandwich panels subjected to double eccentric axial load and failing by propagation of a softening fracturing kink band. Finally, the seventh section shows that skin imperfections, considered to be proportional to the first eigenmode of wrinkling, lead to strong size dependence of the nominal strength of sandwich structures failing by skin wrinkling.


Flexural Strength Composite Laminate Linear Elastic Fracture Mechanic Sandwich Panel Fracture Process Zone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Most of the work reviewed in this paper was sponsored by ONR from the program directed by Dr. Y.D.S. Rajapakse during the years 1994–2005.


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.School of EngineeringDemocritus University of ThraceXanthiGreece
  2. 2.Department of Civil Engineering and Material ScienceNorthwestern UniversityEvanstonUSA

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