Issue 60

Fady Awad et alii, Frattura ed Integrità Strutturale, 60 (2022) 291-309; DOI: 10.3221/IGF-ESIS.60.21

Figure 6: The flexural behavior of ECC layered beam under ultimate loading.

Deflection @ First Crack (mm)

Deflection @ Yield Load (mm)

Deflection @ Breaking Load (mm)

First Crack Load (KN)

Yield Load (KN)

Ultimate Load (KN)

Beam No.

3.5

0.39

14.4

1.582

27.9

9.271

Beam 01

18.2

0.97

101.7

7.938

107.55

10.519

Beam 02

3.335

0.71

.........

..........

108.6

10.65

Beam 03

1.6

0.294

133.8

12.294

142

19

Beam 04

3.6

0.893

.........

..........

148

12.4

Beam 05

Table 5: Features of load deflection values such as first crack, yielding, ultimate and failure.

100 120 140 160

B01 : Control beam B02 : Epoxy grouve B03 : ECC grouve B04 : ECC plate B05 : ECC U plate

0 20 40 60 80

Load (KN)

0 20 40 60 80 100 120 140 160

Deflection (mm)

Figure 7: Load deflection curve for various beams.

Load – (Concrete/ECC/Steel strain) Curve Fig. (4) illustrates strain location at the mid-span of the steel bar and the beam body. Strain readings were recorded from the attached strain gages during testing a data gaining system. Fig. (8A, 8B) shows the load versus concrete/steel strain for the strengthened beams. Crack patterns and failure modes Figures below show all tested beams' crack patterns and failure modes; some of the tested girders failed due to compound failure (flexural, Rupture, and shear). In general, the cracks start in the middle of the lower span; then, the number of these cracks increases, and as the applied load increases, another crack near the support appears to break down gradually.

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