Investigations in Size Dependent Torsions and Fractures

  • P. Tong
  • D. C. C. Lam
  • F. Yang
  • J. Wang
Conference paper
Part of the Solid Mechanics and Its Applications book series (SMIA, volume 114)


Size effects of fine structures due to stain gradients were exhibited experimentally and theoretically in elastic bending of micrometer and nanometer size beams. The Saint-Venant torsion theory of cylinders are extended to explore the relationship between strain gradients and size dependent phenomena. The prediction of the extended torsion theory is in good agreement with experimental data. Furthermore, a higher order J-integral criterion for fracture, which accounts for strain gradients, and its application are reported.

Key words

strain gradients size dependence elasticity torsion fracture J integral 


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Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • P. Tong
    • 1
  • D. C. C. Lam
    • 1
  • F. Yang
    • 1
    • 2
  • J. Wang
    • 1
    • 2
  1. 1.Department of Mechanical EngineeringThe Hong Kong University of Science and TechnologyClear Water Bay, Kowloon, Hong KongChina
  2. 2.Institute of Computational Engineering and ScienceSouthwest Jiaotong UniversityChengdu, SichuanChina

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