PSI - Issue 47

Caroline Bremm et al. / Procedia Structural Integrity 47 (2023) 261–267 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 2. Numerical models and boundary conditions considered in: (a) Model A just with DEs and (b) Model B using DEs and FEs.

In Table 1 are listed the number of cubic modules employed for the three different slenderness levels (height/width ratio - h / b ) examined. The side, b, of the constant square cross section, is equal to 100 mm, whereas for the circular cross section, b is the diameter and also equal to 100mm. For each model, the cubic module length, L , is assumed to be equal to 5 mm. In the Model B, the FE discretization is independently of the slenderness level or cross section shape and consist in 20x20x4 elements (see Fig. 2b). Four different random fields are generate for each case to obtained statistical results.

Table 1. Discretization employed by considering different slenderness level and cross section shape. Cross section/sizes in mm Slenderness level ( h / b ) Discretisation (No. of modules) Square / 100x100x50 0.5 4000 Square / 100x100x100 1.0 8000 Square / 100x100x200 2.0 16000 Circular / 100x200 2.0 12000

The parameters characterising the LDEM constitutive laws are listed in Table 2. The material properties of the steel platens, simulated using FEs in Model B, are also shown.

Table 2. LDE model parameters and steel mechanical properties. Properties Concrete

Steel 200.0

E [GPa] ρ [kg/m³]

32

2300 0.25

7850.0

0.3

ν

1.16E-04 0.005812

ε p ε u

G f [N/m] Lcor [m]

156 0.04

4. Results and discussion Fig. 3 shows the variation in axial compression strength obtained by numerical simulation with the Model A and Model B against the slenderness level for different boundary conditions (Fixed and Frictionless). It can be observed that Model A and Model B have similar trends.