Issue 72

H. S. Vishwanatha et alii, Fracture and Structural Integrity, 72 (2025) 80-101; DOI: 10.3221/IGF-ESIS.72.07

(c) B-LB250

(d) B-VB500

(e) B-HB1000 Figure 10: Load-CMOD and Load-CTOD plots.

As shown in Fig.11, no microcracks are observed in the concrete material when the load is below 40% of the peak load. During this phase, the P-CMOD curve remains nearly linear, signifying a linear elastic stage with only a slight difference between CMOD and CTOD. Once the load exceeds the proportionality limit, the difference between CMOD and CTOD progressively increases with the applied load. As crack propagation occurs, the rotation angle between the crack mouth and crack tip increases, further amplifying the variation in COD values.

Figure 11: CTOD versus Percentage of Peak loading during pre peak and post peak.

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