Snap-back softening instability in high-strength concrete beams
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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.
KeywordsFracture Toughness Linear Elastic Fracture Mecha Crack Depth Crack Mouth Opening Displacement Initial Crack Length
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