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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
Article

Abstract

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.

Keywords

Fracture Toughness Linear Elastic Fracture Mecha Crack Depth Crack Mouth Opening Displacement Initial Crack Length 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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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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