Issue 53

J. Akbari et alii, Frattura ed Integrità Strutturale, 53 (2020) 92-105; DOI: 10.3221/IGF-ESIS.53.08 97 Experiment Numerical API (650) Euro code (8) NZSEE Malhotra et al. [19] Surface wave height (cm) 8.0 8.9 16 13 14 16 Base shear force (kN) 40.7 47.3 37.3 44.3 39.4 45.9 Overturning moment (kN.m) 65.1 28.9 21.8 29.0 25.0 30.6 Axial shell stress (MPa) 25.8 20.5 N/A N/A 51.8 N/A Table 1: A comparison of responses between numerical and experimental methods and regulations codes N UMERICAL R ESULTS ig. 6 illustrates a schematic of the tank and its details. The unanchored roofless tank rests on a rigid bed. Tab. 2 provides the specifications of the material. The shell thickness varies at different heights. The fluid is water in the heights of 6, 9, and 12, occupying 50%, 75%, and 100% of the tank capacity, respectively. The Young modulus (E), Passion’s index ( ν ), and density ( ρ ) of 210 GPa, 0.3, and 7800 kg/m 3 were applied to the tank material. Moreover, the density, bulk modulus, and wave speed of 1000 kg/m 3 , 2200 MPa, and 1449 m/s were applied to the water, respectively. Figure 6: A schematic of the tank and the corresponding FEM mesh. Six models with different fluid levels were incorporated. Tab. 2 provides the models. Model Fluid Height (m) Occupied Tank Capacity (%) Record T1 6 50 1940 El Centro T2 9 75 1940 El Centro T3 12 100 1940 El Centro T4 6 50 1994 Northridge T5 9 75 1994 Northridge T6 12 100 1994 Northridge Table 2: The models and applied earthquake records for numerical studies F