PSI - Issue 5

B. Moussaoui et al. / Procedia Structural Integrity 5 (2017) 163–170 Moussaoui Boualem , Ait tahar Kamal &Bouamra Youcef / StructuralIntegrity Procedia 00(2017) 000 – 000

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The analysis of the results allows us to draw the following conclusions: The figure 2 clearly shows that the strength and ductility of concrete cylinders are dependent of the state of damage of the concrete and the thickness of the polymer tube. The ultimate strength values of various confined concrete cylinders are plotted in Figure 3. Increasing the thickness of polymer tube causes increase strength and ductility of the specimen and the confinement effect is very important for the damaged concrete cylinder comparatively to the reference concrete cylinder. In the elastic phase (start of loading), the evolution of the force - displacement is described by a linear line. All confined and unconfined undamaged concrete cylinders are in a non-cracked state. The confinement rate produced by the polymer tube is very low, or negligible.

10 15 20 25 30

10,00 15,00 20,00 25,00 30,00 35,00 40,00

 (Mpa)

 (MPa)

a) a)

b)

Concrete Reference Confined Concrete -PT 1 Confined Concrete -PT2 Confined Concrete-PT3

Confined Concrete-PT1 Confined Concrete -PT3 Confined Concrete -PT2 Concrete Refernce

0 5

0,00 5,00

 ‰

 ‰

0

10

20

30

40

0 1 2 3 4 5 6 7 8 9 10 11 12

Figure2- Stress – Strain curves comparison: a) Undamaged concrete, b) Damaged concrete

10 15 20 25 30 35 40

MPa

35,08

32,81

29,27

25,2

22,73

19,02

Damaged concrete Undamaged concrete

15,96

11,18

0 5

CC Ref

CC 1 PT CC 2 PT CC 3 PT

Figure3- Ultimate strength values for all tested concrete cylinders