PSI - Issue 28

5

Author name / Structural Integrity Procedia 00 (2019) 000–000

Jamal A. Abdalla et al. / Procedia Structural Integrity 28 (2020) 1295–1302

1299

(a)

(b)

(c)

0.03

6000

1

0.02

4000

SG1 SG2 SG3 SG4

0.5

0.01

2000

Slip (mm)

Load (kN)

Stress (MPa)

0

0

0

0

100

200

0

100

200

0

200 400 600

Distance (mm)

Distance (mm)

Strain (  )

(d)

(e)

(f)

0 100 200 300 400 500

6000

1

4000

Strain(  )

0.5

2000

Load(kN)

Stess (MPa)

0

0

0

0.02

0.04

0

100

200

0

1

2

Slip (mm)

Distance (mm)

Extension (mm)

0.2P

0.4P

0.6P

0.8P

1.0P

Fig. 4. Specimen 20-P-L4 (a) stress-distance; (b) slip-distance; (c) load-strain; (d) shear stress-slip (e) strain-distance; (f) load-extension.

3.2. Effect of concrete strength and bonded length on ultimate Load As formerly stated, all specimens were tested up to failure and the load and extension were recorded at all stages of loading. It can be deducted from Fig. 5 that samples strengthened with AA-R plates exhibit significantly higher averaged loads compared with that of the AA-P strengthened samples. For AA-P specimens, the failure load increases with the increase in the bonded length for each compressive strength, however the variation of concrete strength with same bonded length seems to have little effect on the failure load due to the fact that concrete strength is not contributing in resisting debonding.

10,0 12,0 14,0 16,0

20,0

15,0

0,0 2,0 4,0 6,0 8,0

10,0

Ultimate load (kN)

5,0

Ultimate load (kN)

L1 = 50 mm L2 = 100 mm

L3 = 150 mm

L4 = 200 mm

0,0

fc=20 MPa fc=30 MPa fc=40 MPa fc=60 MPa

AA‐R AA‐P

AA‐R AA‐P

(a)

(b)

Fig. 5. Comparison of average ultimate load of AA plain and AA rough surfaces; (a) based on concrete strength; (b) based on bonded length