PSI - Issue 47

Panagiotis N. Lymperopoulos et al. / Procedia Structural Integrity 47 (2023) 274–281 Panagiotis N. Lymperopoulos, Efstathios E. Theotokoglou / Structural Integrity Procedia 00 (2022) 000–000

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According to Fig. 2 it is observed that our results for the displacements are convergent, with few elements at each rod. For this reason, it was chosen to use 4 elements per rod, in order to describe better the rod geometry. In the sequel, different pentamode structures have been examined, with and without confinement plates. At first a comparison of the calculation of shear strength under static and under harmonical loading (Fig. 3) is made in the case of D/a= 0.0418 (Fig.1).

Fig. 3. Dynamic vs. Static G c

According to Fig. 3, it is observed that the G c values calculated under harmonical loading appear to decrease as the loading frequency increases, but the percentage differences between static and of harmonical loading conditions are rather small. So, the G c under harmonical loading conditions between 0Hz to 10Hz is similar to G c under static loading conditions (Fig. 3). Furthermore, a comparison of G c and E c for pentamodes with different heights and without confinement plates is made (Fig. 4-7).

Fig. 4. G c for different pentamode heights

Fig. 5. E c for different pentamode heights