# Analysis of Macroscopic Traffic Network Impacted by Structural Damage to Bridges from Earthquakes
## 4 Analysis  
Simulation output for the no damage scenario is provide in Table 4. According to the results, average travel time ranged from 0.08 min to 0.85 min per bridge and average travel speed ranged from 37.2 km/h to 57.3 km/h. Traffic volume displayed a larger range. Simulation output for the minor damage scenario is provided in Table 5. According to the results, average travel time ranged from 0.14 min to 2.24 min per bridge and average travel speed ranged from 12.6 km/h to 35.3 km/h. Due to lane closure and reduction in speed limit, average travel time increased while average travel speed decreased in this scenario. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Travel Time (min)** & **Speed (km/h)** & **Traffic Volume** \\ \hline
**No.1 bridge 10 Lanes 60 km/h** & 0.85 & 45.1 & 32,105 \\ \hline
**No.2 bridge 6 Lanes 60 km/h** & 0.80 & 56.9 & 9900 \\ \hline
**No.3 bridge 7 Lanes 60 km/h** & 0.51 & 51.2 & 14,529 \\ \hline
**No.4 bridge 5 Lanes 80 km/h** & 0.58 & 49.7 & 33,314 \\ \hline
**No.5 bridge 4 Lanes 40 km/h** & 0.36 & 37.2 & 3987 \\ \hline
**No.6 bridge 6 Lanes 50 km/h** & 0.09 & 46.4 & 6139 \\ \hline
**No.7 bridge 7 Lanes 60 km/h** & 0.08 & 57.3 & 6012 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: No damage scenario simulation results. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**No Damage**} & \multicolumn{2}{c}{**Minor Damage**} & \multicolumn{2}{c}{**Moderate Damage**} & \multicolumn{2}{c}{**Major Damage**} \\ \cline{2-9}  & **Lanes in** & **Speed** & **Lanes** & **Speed** & **Lanes** & **Speed** & **Lanes** & **Speed** \\  & **Use** & **Limit** & **in Use** & **Limit** & **in Use** & **Limit** & **in Use** & **Limit** \\ \hline
**No.1 Bridge** & 10 & 60 & 8 & 40 & 4 & 20 & 2 & 10 \\ \hline
**No.2 Bridge** & 6 & 60 & 4 & 40 & 2 & 20 & 2 & 10 \\ \hline
**No.3 Bridge** & 7 & 60 & 4 & 40 & 2 & 20 & 2 & 10 \\ \hline
**No.4 Bridge** & 5 & 80 & 2 & 60 & 2 & 40 & 2 & 20 \\ \hline
**No.5 Bridge** & 4 & 40 & 2 & 30 & 2 & 20 & 2 & 10 \\ \hline
**No.6 Bridge** & 6 & 50 & 4 & 30 & 2 & 20 & 2 & 10 \\ \hline
**No.7 Bridge** & 7 & 60 & 4 & 40 & 2 & 20 & 2 & 10 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Bridge operation scenarios. Simulation output for the minor damage scenario is provide in Table 6. According to the results, average travel time ranged from 0.25 min to 4.29 min per bridge and average travel speed ranged from 7.6 km/h to 16.9 km/h. Simulation output for the minor damage scenario is provide in Table 7. According to the results, average travel time ranged from 0.45 min to 17.81 min per bridge and average travel speed ranged from 2.0 km/h to 11.8 km/h. Table 8 and Figure 4 display average travel time comparisons for the selected scenarios. As expected, major damage scenario shows the most increase in average travel time. Bridges connecting southern and northern part of the city (Bridges 1 through 4) had greater increase compared to other bridges (Bridges 5 through 7). Table 9 and Figure 5 show average travel speed comparisons. Similar to the travel time comparison, Bridges 1 through 4 demonstrate higher speed reduction. Bridge 5 was less affected by the earthquakes showing the least speed decrease and travel time increase. It is believed that Bridges 1 through 4 are more critical to serve the northbound and southbound traffic, while Bridge 5 is positioned to handle relatively small number of traffic volume in northeast corner of the city. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Travel Time (min)** & **Speed (km/h)** & **Traffic Volume** \\ \hline
**No.1 bridge 4 Lanes 20 km/h** & 4.29 & 8.8 & 28,969 \\ \hline
**No.2 bridge 2 Lanes 20 km/h** & 3.70 & 12.4 & 11,593 \\ \hline
**No.3 bridge 2 Lanes 20 km/h** & 3.21 & 8.04 & 14,149 \\ \hline
**No.4 bridge 2 Lanes 40 km/h** & 3.7 & 7.6 & 32,707 \\ \hline
**No.5 bridge 2 Lanes 20 km/h** & 0.73 & 17.3 & 3083 \\ \hline
**No.6 bridge 2 Lanes 20 km/h** & 0.25 & 16.8 & 3523 \\ \hline
**No.7 bridge 2 Lanes 20 km/h** & 0.29 & 16.9 & 3455 \\ \hline \hline \end{tabular}
\end{table}