PSI - Issue 62

Nico Di Stefano et al. / Procedia Structural Integrity 62 (2024) 809–814 Nico Di Stefano, Anna Bontempi, Paolo Pizzini, Fausto Minelli / Structural Integrity Procedia 00 (2019) 000 – 000

813

5

Table 2: Rebars properties for beam N1.

Beam N1 (No corrosion)

Beam N1 (Corroded)

Longitudinal (m corr =3.8%)

Properties

Longitudinal

Cross section area [mm 2 ]

3584 39.0

3448 38.3

Diameter [mm]

Yield strength [MPa] Ultimate strength [MPa] Elastic Modulus [MPa]

287 412

287 412

203000

203000

Ultimate strain [%]

21.8

21.8

Table 3: Rebars properties for beam N2.

Beam N2 (No corrosion)

Beam N2 (Mean corrosion)

Beam N2 (Max corrosion)

1° Layer (m corr =3.8%)

2° Layer (m corr =2.8%)

1° Layer (m corr =10.4%)

2° Layer (m corr =10.4%)

Properties

1° Layer

2° Layer

Cross section area [mm 2 ]

4072 36.0

982 25.0 325 469

3916 35.3

951 24.6 325 469

3648 34.1

880 23.2 325 469

Diameter [mm]

Yield strength [MPa] Ultimate strength [MPa] Elastic Modulus [MPa]

287 412

287 412

287 412

203000

206000

203000

206000

203000

206000

Ultimate strain [%]

21.8

18.1

21.8

18.1

21.8

18.1

In the first case, beam N1 (Figure 6a) the ultimate resistance is nearly the same for experimental, uncorroded and corroded models. This was quite expected, in fact the corrosion rate of the longitudinal rebars was low and, although the stirrups corrosion was much more severe, it has not much influenced the mechanism, which was clearly flexural. The maximum load values of beam N1 test and analyses are shown in Table 4.

Table 4: Max Load of beam N1 test and analyses.

P max [kN]

P Exp /P Max [%]

Experimental

873

100%

No corrosion

870

100%

Mean corrosion

842

96%

For beam N2, corrosion was simulated through two different scenarios, considering the mean and the maximum value of longitudinal reinforcement corrosion rate respectively. Table 5 and Figure 6b shows that the model with the maximum value of corrosion, was the most accurate in terms of maximum load and beginning of the plateau. Moreover, we can underline that, in this second test, the reduction in beam resistance was significant, of about the 19%, with respect to the uncorroded analysis.

Table 5: Max Load of beam N2 test and analyses.

P max [kN]

P Exp /P max [%]

Experimental No corrosion Mean corrosion 10.4% corrosion

1200 1426 1365 1218

100% 119% 114% 101%