Materials and Structures

, Volume 22, Issue 6, pp 429–436 | Cite as

Snap-back softening instability in high-strength concrete beams

  • L. Biolzi
  • S. Cangiano
  • G. Tognon
  • A. Carpinteri


Three-point bending tests on pre-cracked slabs of high-strength concrete are interpreted on the basis of a virtual crack propagation model. As theoretically shown by the model, a snap-back softening instability appears only for initial crack lengths smaller than 0.3 times the beam depth. As a limit-case, when the material is sufficiently brittle or the specimen size is sufficiently large, such an instability can be predicted by the LEFM condition K1=KIC.


Fracture Toughness Linear Elastic Fracture Mecha Crack Depth Crack Mouth Opening Displacement Initial Crack Length 
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Copyright information

© RILEM 1989

Authors and Affiliations

  • L. Biolzi
    • 1
  • S. Cangiano
    • 2
  • G. Tognon
    • 2
  • A. Carpinteri
    • 3
  1. 1.Institute of Theoretical and Applied MechanicsUniversita di UdineUdineItaly
  2. 2.ITALCEMENTIBergamoItaly
  3. 3.Department of Structural EngineeringPolitecnico di TorinoTorinoItaly

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