# Dynamic Responses of Liquid Storage Tanks Caused by Wind and Earthquake in Special Environment
## 6 Numerical Example
### Influences of Wind Speed on Dynamic Responses  
Through the above analysis, it has been found that the influence of wind load on the liquid storage tank cannot be ignored. In order to further discuss the responses of the liquid storage tank under wind load, a comparative study is carried out under the wind speed of 10 m/s and 20 m/s. The nephograms of the effective stress, displacement, and base shear force are shown in Figures 9-11 and Table 3.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Dynamic Responses** & **Actions** & **Maximum Absolute Value** \\ \hline \multirow{3}{*}{Effective stress/MPa} & Wind & 106.50 \\  & Earthquake & 74.62 \\  & Wind and earthquake & 117.03 \\ \hline \multirow{3}{*}{Displacement/mm} & Wind & 6.38 \\  & Earthquake & 4.23 \\  & Wind and earthquake & 7.55 \\ \hline \multirow{3}{*}{Base shear force/kN} & Wind & 92.88 \\  & Earthquake & 240.41 \\ \cline{1-1}  & Wind and earthquake & 756.75 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Absolute maximum dynamic response under different actions.  
Figure 8: Comparison of tank base shear force (unit: N). (**a**) Wind. (**b**) Earthquake. (**c**) Wind and earthquake.  
As shown in Figures 9-11, under the combined action of wind and earthquake, when the wind speed is 10 m/s, the location of maximum effective stress and displacement of the tank is located in the liquid filled area at the bottom of the liquid storage tank, but when the wind speed increases to 20 m/s, the location of maximum effective stress and displacement of the structure shifts to the unfilled area at the bottom of the liquid storage tank. The maximum effective stress and displacement of the structure shifts to the unfilled area at the bottom of the liquid storage tank, is located in the liquid storage tank, but when the wind speed increases to 20 m/s, the location of maximum effective stress and displacement of the structure shifts to the unfilled area at the bottom of the liquid storage tank.  
Figure 11: Effect of wind speed on tank base shear force (unit: N).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Wind Speed**} & \multicolumn{3}{c}{**Dynamic Responses**} \\ \cline{2-4}  & **Effective Stress/MPa** & **Displacement/mm** & **Base Shear Force/kN** \\ \hline
10 m/s & 117.03 & 7.55 & 756.75 \\
20 m/s & 218.96 & 13.13 & 951.11 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Effect of wind speed on absolute maximum dynamic responses.  
Figure 10: Effect of wind speed on tank displacement (unit: m).  
Figure 9: Effect of wind speed on tank effective stress (unit: Pa).  
the upper part of the liquid storage tank. That is to say, when the wind speed is lower, the responses of liquid storage tanks are dominated by earthquake, on the contrary, when the wind speed is higher, the responses of liquid storage tanks will be dominated by wind.  
As shown in Table 3, when the wind speed is increased by 2 times, the effective stress, displacement, and base shear force are significantly increased, especially the effective stress and displacement are approximately increased by 2 times.  
Therefore, when the wind speed is high, the probability of damage to the liquid storage tank is relatively high. For liquid storage tanks built in special areas, sufficient attention should be paid to the adverse effects of wind load.