Issue 61

R. Elsadany et alii, Frattura ed Integrità Strutturale, 61 (2022) 294-307; DOI: 10.3221/IGF-ESIS.61.20

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Theoretical and experimental ultimate loads are compared in Table 8. There is a good agreement between them. Crack pattern and Mode of Failure Crack pattern and mode of failure of steel RC beams are typical of under-reinforced RC beam behavior, as shown in Fig. 5. a and b. The first crack loads ranged from 15 to 39 kN based on the tensile reinforcement ratio and concrete type, see table 7. In general, steel RC beams with RCA had lower first crack loads than steel RC beams without RCA, as listed in table 7. Flexural cracks propagate upwards as loading progress but remain very narrow throughout the loading history. With increasing load, flexural-shear cracks initiated propagated towards the point of load. With a further increase in the applied load, crushing of concrete at the top compression side around the point of load application occurred at the ultimate load after yielding steel reinforcement. On the other hand, all GFRP RC beams failed due to concrete crushing in the compression zone, i.e., brittle failure, except beam BNG1, which failed due to the rupture of tensile GFRP bars, i.e., catastrophic failure, Fig. 5. c-e.

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