Geometrically nonlinear determination of energy release rate and mode ratio in single leg bending tests

B. D. Davidson, Amitabh Bansal, Bing Qida Bing, Sun Xuekun Sun

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Geometrically linear and nonlinear finite element analyses are used to determine the energy release rate and mode ratio in simulated tests of unidirectional, symmetric, single leg bending (SLB) specimens. It is shown that the finite diameter loading rollers that are typically used in practical test set-ups cause this test to be inherently nonlinear. The differences between the linear and nonlinear results are presented parametrically as a function of material properties, specimen thickness, roller diameter, span length and crack length. These results are used, along with empirically derived equations, to develop an approach for designing SLB experiments where one will have a high degree of confidence in toughness values as obtained from conventional data reduction techniques, and for which relatively little specimen-to-specimen variation in mode ratio will be observed.

Original languageEnglish (US)
Pages (from-to)1881-1901
Number of pages21
JournalJournal of Reinforced Plastics and Composites
Issue number15
StatePublished - Aug 2009


  • Delamination
  • Energy release rate
  • Epoxy
  • Finite element
  • Glass
  • Graphite
  • Mixed-mode
  • Mode ratio
  • Nonlinear
  • Single leg bending
  • Toughness

ASJC Scopus subject areas

  • Ceramics and Composites
  • Mechanics of Materials
  • Mechanical Engineering
  • Polymers and Plastics
  • Materials Chemistry


Dive into the research topics of 'Geometrically nonlinear determination of energy release rate and mode ratio in single leg bending tests'. Together they form a unique fingerprint.

Cite this