PSI - Issue 37

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Rogério Lopes et al. / Procedia Structural Integrity 37 (2022) 123–130 R. F. Lopes et al. / Structural Integrity Procedia 00 (2019) 000 – 000

Fig. 3. Representation of the boundary conditions applied to the door

2.2. Numerical modelling using PamCrash The initial model is preprocessed in Abaqus , was now imported into PamCrash , in order to take advantage of the work previously carried out. Therefore, the FEM mesh will be equal, although the element types are different. The supports will have the same restricted degrees of freedom. For the shell elements a Belytschko – Tsay shell formulation, with reduced integration was used. For the beam elements, a 0 Timoshenko theory was used. These shell elements have hourglass control, and the formulation is explicit at low velocity. 3. Results The comparison between the numerical results and the experimental results, obtained in the PSD test are shown in Fig. 4. three force / displacement curves are shown, respectively the experimental curve extracted directly from the load cell, and two other curves from the numerical results obtained using different numerical tools. In a quick check, it is evident that the plastic behavior of the materials that composes the structure is quite close, for both software.

Fig. 4. Comparison of experimental and numerical data of force/displacement, in both software

However, the higher differences are verified in the elastic behavior. Focusing on the comparison of the FEM software, it appears that the structure simulated by Pamcrash is more compliant, which allows a significantly better approximation to the experimental results. Also, a positive factor is the simulation calculation time using this tool is extremely faster. In fact, the simplification of connections of the given structure using tie constraint can induce additional stiffness, which can make the structure stiffer than the reality. Another point that should be mentioned is