PSI - Issue 84

Mohammad Javad Azari Nezhadian et al. / Procedia Structural Integrity 84 (2026) 1222–1230

1228

Cracking patterns shown in Fig. 6 reinforce the response based on the recorded curves. For both specimens, vertically oriented flexural cracks formed at the intrados and grew upwards as the load was increased. Over the central region, crack spacing stayed fairly uniform, consistent with the almost constant-moment zone of the test configuration, consistently with the preliminary simplified analytical study shown in Fig. 7. At higher load levels, some of the cracks opened significantly, reflecting concentration of tensile stresses along with a limited number of dominant cracks. In the final stage of loading, localized crushing developed along the extrados near the load application points, and substantial openings appeared on the intrados, confirming that failure had indeed been controlled by bending rather than shear. The absence of diagonal cracking further reinforces this view.

Fig. 6 Sections A and B, respectively, show the cracking patterns observed in specimen IV and VII after the completion of the bending test.