Issue 61

V.-H. Nguyen et alii, Frattura ed Integrità Strutturale, 61 (2022) 198-213; DOI: 10.3221/IGF-ESIS.61.13

are observed to fail in the form of ultimate flexural strength, not be failed by shear failure modes. Also, the stress of the external plate based on Raoof et al. [20] includes the upper and lower threshold stresses. As observed, the range of stress change is smaller than the experimental value. It can be inferred that brittle rupture may be the reason that the stresses in the steel do not reach the yield strength. In the present experimental beams, the beams have been designed, so that brittle failure does not occur but is ductile. Thus, the measured stresses are higher than those predicted by Raoof et al [20].

Figure 7 : Results of steel plate strain versus testing force at mid span.

Figure 8 : Results of steel plate strain versus testing force at left ends.

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