Issue 68

G. S. Silveira et alii, Frattura ed Integrità Strutturale, 68 (2024) 77-93; DOI: 10.3221/IGF-ESIS.68.05

In this context, σ t and σ c denote the tension and compression stresses. Additionally, f t and f c are the stress levels associated with inelastic deformation. This simplification aids in explaining the progression of damage, which becomes evident after the concretes represents the accumulation of damage for the different concrete types under study in Figs. 12 and 13.

9

150

UHPFRC UHPC NSC

UHPFRC UHPC NSC

8

125

7

6

100

5

75

4

50 Stress (MPa)

Stress (MPa)

3

2

25

1

01234567891011 0

0

0

1

2

3

4

5

6

7

8

Inelastic strain (‰)

Inelastic strain (%)

Figure 10: Inelastic stress-strain under uniaxial compression.

Figure 11: Inelastic stress-strain under uniaxial tension.

Concrete LSC [23]

Poisson’s ratio

Modulus of elasticity

Compression stress

Tension stress

17039 MPa 26064 MPa 45000 MPa 43000 MPa

9 MPa 25 MPa

1.86 MPa 1.65 MPa 3.00 MPa 8.00 MPa

NSC

0.20

UHPC [36]

135 MPa

UHPFRC [36]

Table 3: Parameters of concrete input the model on Abaqus.

1.00

1.0

0.8

0.75

0.6

0.50

0.4

Damage of tensile index

UHPFRC UHPC LSC NSC

UHPFRC UHPC LSC NSC

0.25

0.2

Damage of compression index

0.0

0.00

0.00

0.01

0.02

0.03

0.04

0.05

0.00

0.02

0.04

0.06

Inelastic strain

Inelastic strain

Figure 12: Damage of compression index.

Figure 13: Damage of tensile index.

Analysis of mesh size convergence The mesh selection process followed a thorough mesh convergence study to ensure comprehensive computational simulation. This study covered mesh convergence values ranging from 25 to 50 mm, and achieving convergence involved refining the numerical model related to the LSC element to align it with the experimental model conducted by Cosgun et al. [22]. The analysis accounted for the effective influence of Concrete Damaged Plasticity (CDP) behavior in Fig. 14 depicts the mesh convergence study considering the element's behavior without damage effects (i.e., plastic behavior). In Fig. 15,

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