Issue 48

C.A.C.P. Coelho et alii, Frattura ed Integrità Strutturale, 48 (2019) 411-418; DOI: 10.3221/IGF-ESIS.48.39 413 of 1.88 ms -1 . This energy was previously selected in order to promote damage, but without perforation of the specimens. The impact tests were performed according to ASTM D7136 standard and, for each configuration, five specimens were tested at room temperature. Flexural tests were also performed using a Shimadzu AG-100 universal testing machine (Kyoto, Japan), with the same support and loading nose shown in Fig. 2, equipped with a 100 kN load cell at a displacement rate of 3 mm/min. All tests were also carried out at room temperature, and five specimens were tested for each configuration. All results will be discussed in terms of average values. a) b) Figure 1 : a) View of the manufacturing process and mold; b) Geometry and dimensions of the specimens (thickness 1.4±0.1 mm). Figure 2 : General views of the apparatus (support) used in the experimental tests. R ESULTS AND DISCUSSION n order to understand the impact performance of the different laminate composite semi-cylindrical shells, flexural tests were carried out for each configuration. Fig. 3 shows typical load-displacement curves and Tab. 1 presents the average results, with the respective standard deviation. Stiffness was defined as the slope in the linear region of the load-displacement response and the displacement is the value obtained for the maximum load. I