PSI - Issue 27

Nurul Huda et al. / Procedia Structural Integrity 27 (2020) 140–146 Huda and Prabowo / Structural Integrity Procedia 00 (2019) 000 – 000

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2. Finite element analysis verification The finite element model and boundary conditions are showed in Fig. 2. The model’s dimension is 1200 mm (diameter) × 1500 mm (height). The top end is applied rolled constraint, center hollow pipe constrain only allowed axial vertical displacement, and full body submerged with non-uniform hydrostatic pressure load.

Fig. 2. The finite element model and boundary conditions.

3. Material selection When moored in the oceanic environment, surface buoys are subjected to wind action, wave action, oceanic currents, and sometimes icing. Subsurface buoys must resist considerable hydrostatic pressure (Berteaux, 1976). In addition, buoys are submitted to severe loads during deployment and retrieval. Undersea environment, requires of

material are as follows (Ross, 2006): • High resistance to water pressure; • Good corrosion resistanc e; • Good sound absorption performance; • High strength: weight ratio;

• Long service life; • Acceptable price.

Resin-based composite materials Polyester/E-glass, Vinyl ester/E-glass, Epoxy/E-glass can meet the above requirements. The three materials’ fibe rs are all unidirectional E-glass, but matrixes are different. Comparisons of matrix properties are shown in Table 1 (Bureau Veritas, 2017). Differences in matrix properties of different composites’ properties, elastic properties of the three composite mat erials are displayed in Table 2 (Bureau Veritas, 2017).