Issue 60

A.-A. A. A. Graf et al., Frattura ed Integrità Strutturale, 60 (2022) 310-330; DOI: 10.3221/IGF-ESIS.60.22

Concrete was simulated using a multilinear isotropic hardening model. The stress-strain curve was used to simulate the concrete plasticity based on equations 1 and 2 [16]. The concrete material properties are given in a Tab. 3.



E

c



f

(1)

2

        0 

1

'

2 c c f E

  0

(2)

where, E c is Young’s modulus for concrete, ε is the concrete strain, and ε 0 is the compression failure strain.

Ultimate compressive strength

Tensile strength

Modulus of elasticity Poisson’s ratio

65 MPa

3 MPa

38 GPa

0.2

Table 3: Concrete material model properties

Uniaxial concrete tensile cracking stress was simulated according to the SOLID65 cracking model, as shown in Fig. 7.

Figure 7: Strength of cracked condition.

The numerical model was validated by comparing the obtained numerical results for the control beam with the experimental data found in [17]. While sensitivity analysis was done by studying the element size effect 20, 30, and 40 mm on the steel stress results at 40 KN. The results in Fig. 8.a and Fig. 8.b show that the developed numerical model is acceptable for simulating the problem and the mesh element sizes 20, 30, and 40 mm have the same results, therefore, 25 mm element size was selected to model all beams.

a) Element mesh size sensitivity.

b) Numerical validation.

Figure 8: Results validation; a) Element mesh size sensitivity, b) Numerical validation.

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