Issue56

K. Fawzy et al, Frattura ed Integrità Strutturale, 56 (2021) 123-136; DOI: 10.3221/IGF-ESIS.56.10

load deflection curve at yielding of tension steel. Oudah and Hash [17] recently published a new definition of ductility, a model based on beam deflection and energy. The ductility indexes can be described as: Deflection ductility: μ∆ = ∆ u/ ∆ y (1) Energy ductility: μ E = Eu/Ey (2) Tab. 6 displays the energy and deflection ductility of the prepared RC beams reinforced by using different combinations of CFRP. It was also found that the beam without strengthening displayed greater displacement or ductility relative to concrete beams of different CFRP configurations.

Figure 7: load-deflection curve for one layer with different reinforcement.

At first crack

At steel yield

At failure

Beam No.

Load (kN) 11.80 16.73 26.32 25.59 21.88 13.68 17.47 23.99 15.58 12.17

Deflection (mm)

Load (kN)

Deflection Δ y (mm)

Max Load (kN)

Deflection Δ u (mm)

B 00 B 01 B 02 B 03 B 04 B 05 B 06 B 07 B 08 B 09

1.98

39.9 59.7

8.35

51.20 69.44

32.01 27.72 26.13 23.33 31.74 32.96 36.96 30.97 33.76 36.56

2.1

14.10 14.32 14.88 14.51 16.83 25.61 20.44 23.77 14.27

6.45 3.45 1.51 1.54 2.56 2.17 1.09 1.46

62.72 63.88 60.25 60.15 80.50 71.55

75.1

79.39 75.66 73.76 87.85 88.78 99.06 80.38

88.8

53.07

Table 5: Tested specimen data.

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