PSI - Issue 28

Jamal A. Abdalla et al. / Procedia Structural Integrity 28 (2020) 2342–2349 Author name / Structural Integrity Procedia 00 (2019) 000–000

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3. Results and Discussions All beams have failed in shear. The specimens strengthened with CFRP without anchorage failed by FRP de bonding followed by crushing on top of concrete beam. Table 3 shows the load capacity and the maximum deflection for all tested specimens. It observed from Table 3 that specimens with bore-epoxy anchorage showed an increase in load capacity ranged between 48.18% and 55.97% and an increase in deflection ranging between 52.81% and 63.54%. These ranges are larger than that of the S-EBR specimen.

Table 3. Ultimate load capacity and maximum deflection.

No.

Specimen

Ultimate Load (kN)

Maximum Deflection (mm)

Increase in Load Capacity (%)

Increase in Deflection (%)

1 2 3 4 5

C

112.97 159.70 176.20 173.40 167.40

5.87 8.86 9.31 9.60 8.97

-

-

41.36 55.97 53.47 48.18

50.94 58.60 63.54 52.81

S-EBR

SBN SBM SBL

Figure 4 shows the load-deflection relationships for all five tested specimens. Specimen S-EBR was strengthened in shear with CFRP sheets using EBR method without anchorage and this specimen failed in shear with CFRP de bonding and higher load and higher displacement of 41.36% and 50.94%, respectively, compared to the control beam C0. For the specimens strengthened with EBR on bore-epoxy anchorage (SBN, SBM, SBL) it is clear from Fig. 4 that there is an increase in the load carrying capacity and also in deflection (ductility) as compared to control specimen C0 and S-EBR. The test specimen SBN showed an increase in load capacity up to 55.97 % and deflection of up to 58.60% over the control beam. This proved that the bore-epoxy anchorage managed to delay the debonding failure in CFRP sheets. Similarly, specimens SBM and SBL that are strengthened with CFRP sheets with bore-epoxy anchorage with medium (25 mm) and large (35 mm) bore diameters failed also in shear with load and deflection larger than the control beam as shown in Table 3.

100 120 140 160 180

0 20 40 60 80

Control S-EBR

Load (kN)

SBN SBM SBL

0

2

4

6

8

10

Deflection (mm)

Fig. 4. (a) Load-deflection relationship