## 6 Parameter Analysis
### The Effect of Baffle
Furthermore, the computation time of the present reduced model (\(V_{\text{s}}=1500\) m/s) simulated by the MATLAB procedure is compared with that of the finite element model simulated by ADINA under rigid soil [22] for \(M=2\), \(\beta_{1}=0.5\), \(\beta_{2}=0.75\), \(\beta_{3}=1.0\), \(\gamma=0.5\) and \(R_{2}=1\) m. For each response solution, it only takes approximately 18 s by the present method; however, the ADINA model takes about 508 s [22] on the same personal laptop with Intel Core i7-5500U CPU. Therefore, the present analytical model is 25-30 times faster than the ADINA model. The impacts of the upper baffle height on the maximum convective shear \(F_{\text{max}}^{\text{C}}\) and maximum impulsive shear \(F_{\text{max}}^{\text{I}}\) under NF and FF seismic excitations are illustrated for \(M=2\), \(\beta_{1}=0.2,\ 0.3,\ 0.4\), \(\beta_{3}=1.0\), \(\gamma=0.7\), \(0.8\), \(0.9\) and \(R_{2}=10\) m in Figure 11. It is seen that by increasing the baffle height, \(F_{\text{max}}^{\text{C}}\) monotonically decreases; however, \(F_{\text{max}}^{\text{I}}\) monotonically increases, which is attributed to the fact that the liquid mass corresponding to the impulsive sloshing response is increased with increase in the baffle height [22]. In Figure 12, as the baffle height increases, the maximum of the hydrodynamic shear \(F_{\text{max}}\) increases. The maximum of the hydrodynamic moment \(M_{\text{max}}\) first decreases and then increases. The effects of dimensionless baffle radius on \(F_{\text{max}}^{\text{C}}\) and \(F_{\text{max}}^{\text{I}}\) under NF and FF seismic excitations are investigated for \(M=2\), \(\beta_{1}=0.3\), \(\beta_{2}=0.5,\ 0.6,\ 0.7\), \(\beta_{3}=1.0\) and \(R_{2}=10\) m in Figure 13. It is observed that as the baffle radius increases, \(F_{\text{max}}^{\text{C}}\) monotonically increases; however, \(F_{\text{max}}^{\text{I}}\) monotonically diminishes due to the declined impulsive mass by increasing the inner radius of baffles [22]. In Figure 14, \(F_{\text{max}}\) declines with increase in the baffle inner radius; however, \(M_{\text{max}}\) monotonically increases. Figure 10: Amplitudes for the surface height at the tank wall \(f_{\text{max}}\): (**a**) under the upper baffle height \(\beta_{2}\); (**b**) under the baffle inner radiuses \(\gamma\). Figure 11: The maximum of the hydrodynamic shear for the upper baffle height \(\beta_{2}\): (**a**) the convective shear \(F_{\rm max}^{\rm C}\); (**b**) the impulsive shear \(F_{\rm max}^{\rm I}\). Figure 12: The maximum of the hydrodynamic response for the upper baffle height \(\beta_{2}\): (**a**) the shear force \(F_{\rm max}\); (**b**) the overturning moment \(M_{\rm max}\). Figure 13: The maximum of the hydrodynamic shear force for the baffle inner radius \(\gamma\): (**a**) the convective shear \(F_{\rm max}^{\rm C}\); (**b**) the impulsive shear \(F_{\rm max}^{\rm I}\). Additionally, the maximum hydrodynamic sloshing responses of the tank undergoing NF earthquake motion are larger than those undergoing FF earthquake motion in Figures 11-14, which is attributed to the large amplitude in the range of the lower frequency for power spectral density of NF seismic records. The natural frequencies for the liquid sloshing of the soil-tank system are in proximity to the predominant low frequency of the NF earthquake records. The hydrodynamic responses of the tank are more sensitive to NF seismic action in comparison with FF seismic action. Consequently, attention should be paid to earthquake responses in proximity of active faults.