PSI - Issue 33

Fabio Di Trapani et al. / Procedia Structural Integrity 33 (2021) 896–906 Di Trapani et al./ Structural Integrity Procedia 00 (2019) 000–000

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Table 1. Material properties of concrete and masonry blocks used in ABAQUS

Material

Mass density

Elasticity parameters

Plasticity parameters

Young's modulus (MPa)

Poisson's ratio ν

Dilatation Angle ψ

ton/m 3

Eccentricity  f b0 /f co

K c

Viscosity

Concrete Masonry bricks

2.5E-09

32308

0.3 0.2

37 10

0.1 0.1

1.16 1.16

0.667 0.667

0.0003 0.0003

1.10E-09

3160

Steel reinforcement was modeled using 1D truss elements whose mechanical response is simulated by a simple elasto-plastic with strain hardening material model. Steel rebars were modeled as embedded elements within the concrete, so that relative sliding between steel bars and concrete could not occur. Mortar joints behavior was modeled using elasto-plastic interfaces with friction and cohesion. All the model elements were modeled by solid 3D elements with 8 nodes (C3D8R) with a sufficiently refined mesh. Fig. 1 shows the scheme of the model assembly (Fig. 1a) and the mesh of the elements (Fig. 1b). A non-linear quasi-static analysis was performed to simulate the test. Out-of-plane displacements were imposed at the four loading plates.

Fig. 1. Definition of the micro-model (a) Scheme of the model assembly; (b) Mesh of the model.

Results of the numerical simulation of the OOP test are shown in Fig. 2 and compared with the experimental response. It can be observed that the model is able to effectively reproduce the experimental behaviour in terms of initial stiffness, peak resistance, and the post peak behaviour.

Fig. 2. Comparison between numerical simulation and experimental response of the OOP test 4E by Ricci et al., 2018.

The analysis allowed also an investigation in terms of stress distribution and damage localization. Fig. 3a show the compressive principal stresses on leeward sides of the specimen in correspondence of the peak load. The analysis