Singularities of cracks with generalized finite elements

  • E. Schnack
Conference paper
Part of the Lecture Notes in Mathematics book series (LNM, volume 1121)


Pian's hybrid method is frequently used for computing stress intensity factors in fracture mechanics. It has been shown, however, that this method has its limitations. In using this method, it is found that the resulting stiffness matrix is often poorly conditioned and it is not possible to determine surface displacements of notch or crack zones accurately. Most of these aforementioned difficulties can be eliminated by using a modified hybrid stress model in combination with the displacement method. The proposed modified hybrid method will be shown to offer some significant advantages for plane, axi-symmetric and three dimensionel problems of fracture mechanics.


Stress Intensity Factor Crack Front Crack Opening Displacement Linear Elastic Fracture Mechanic Trial Function 
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Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • E. Schnack
    • 1
  1. 1.Institute of Solid MechanicsKarlsruhe UniversityKarlsruheGermany

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