Analysis of the Semi-circular Bend (SCB) Specimen: Finite Element Method Determination of T-stress, KI and KII

  • E. ShahabiEmail author
  • P. M. S. T. de Castro
Part of the Advanced Structured Materials book series (STRUCTMAT, volume 98)


The semi-circular specimen under three-point bending loading (SCB specimen) may be used for determining mode I and mixed-mode (I and II) fracture toughness for brittle materials; this subject is covered in several references. This paper presents T-stress and stress intensity factor for SCB specimen in mode I and mixed-mode (I and II), exploring direct uses of finite element method to calculate those parameters. The commercial FE software ABAQUS was used to model the SCB specimen. Several cases including different crack lengths for investigating mode I, various crack angles for mixed-mode (I and II) and T-stress are presented. Since SCB specimen is loaded in bending, a comparison of the SCB and SE (B) specimen (ASTM E399-08 standard) was performed for mode I, discussing dimensions and amount of material involved. Finally, the result obtained from the presented finite element model are compared with results from the literature.


T-stress Stress intensity factor Finite element method Mode I Mixed-mode 


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Authors and Affiliations

  1. 1.FEUP, Faculty of EngineeringUniversity of PortoPortoPortugal

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