## 5 Results Analysis
### Simulation Results for Scenarios 1-5
#### 5.2.2 Resilience Loss  
The level of functionality of the system during the time period in which the north tube is partially or completely closed was computed as the ratio between the average travel time required to reach a given destination from a specific origin before and after the occurrence of the disruptive event (obviously in absence of the incidental event in the north tube, the functionality level is assumed to be equal to 100%). In particular, our analysis is related to the average travel time of traffic flow towards the north direction (i.e., from the Nodes A to D). As an example, given that under ordinary conditions of functionality of the north tube, the average travel time of traffic flow from the Nodes A to D is 12.514 min (i.e., Scenario 0, A-D motorway section of Table 3) and the corresponding average travel time of Scenario 1 is 14.233 min when the duration of interruption is 1 h (see Table 4), we computed that the functionality level in the event of the partial closure of the north tube is reduced to: 100 \(\times\) 12.514/14.233 = 87.92%; while in the case of the complete closure of the north tunnel for 1 h of disruption the functionality level is reduced to: 100 \(\times\) 12.514/19.125 = 65.43% (i.e., Scenario 2a); 100 \(\times\) 12.514/21.582 = 57.98% (i.e., Scenario 2b); 100 \(\times\) 12.514/23.185 = 53.97% (i.e., Scenario 2c). Obviously, we computed \begin{table}
\begin{tabular}{c c c c c c c} \hline \multirow{2}{*}{**Scenario**} & \multirow{2}{*}{**Average Speed**} & \multirow{2}{*}{**Average Travel Time**} & \multirow{2}{*}{**Delay Time**} & \multirow{2}{*}{**Average Speed**} & \multirow{2}{*}{**Average Travel Time**} & \multirow{2}{*}{**Delay Time**} \\  & [km/h] & & & **[min]** & **[km/h]** & **[min]** & **[min]** \\ \hline \multicolumn{8}{c}{**On the motorway (for all vehicles) without the use of the alternative itinerary**} \\  & & North direction (A \(\Rightarrow\) D) & \multicolumn{3}{c}{South direction (D \(\Rightarrow\) A)} \\ Scenario 1 & 90.71 & 16.373 & 3.859 & 116.84 & 12.671 & - \\ Scenario 2a & 52.60 & 28.237 & 15.723 & 79.38 & 18.650 & 5.979 \\ Scenario 2b & 45.18 & 32.874 & 20.360 & 79.95 & 18.517 & 5.846 \\ Scenario 2c & 41.48 & 35.806 & 23.292 & 80.97 & 18..284 & 5.613 \\ \multicolumn{8}{c}{**On the motorway (for passenger cars only) when the alternative itinerary is activated for HGVs only**} \\  & & North direction (A \(\Rightarrow\) D) & \multicolumn{3}{c}{South direction (D \(\Rightarrow\) A)} \\ Scenario 3 & 106.20 & 13.985 & 1.471 & 116.84 & 12.671 & - \\ Scenario 4a & 75.54 & 19.662 & 7.148 & 79.38 & 18.650 & 5.979 \\ Scenario 4b & 54.10 & 27.454 & 14.940 & 79.95 & 18.517 & 5.846 \\ Scenario 4c & 47.58 & 31.216 & 18.702 & 80.97 & 18..284 & 5.613 \\ \multicolumn{8}{c}{**On the alternative route ( itinerary: A-B-E-I-L-C-D of Figure 2) when activated for all vehicles (passenger cars and HGVs)**} \\  & & North direction & \multicolumn{3}{c}{North direction} \\ Scenario 5 & 37.34 & 43.946 & 31.432 & \multicolumn{3}{c}{South direction (D \(\Rightarrow\) A)} \\ \hline \end{tabular}
\end{table} 
Table 6: Simulation results: average speed, average travel time, and delay time for the scenarios investigated when the north tube is partially or completely closed for 3 h (for example: Scenario 2c, delay time on the motorway for all vehicles = 35.806 \(-\) 12.514 = 23.292 min; Scenario 4c, delay time on the motorway for passenger cars only = 31.216 \(-\) 12.514 = 18.702 min; Scenario 5, delay time on the alternative itinerary for all vehicles = 43.946 \(-\) 12.514 = 31.432 min). the reduction of the functionality level for all the remaining scenarios investigated in a similar way. It is to be stressed that higher values of the mentioned percentage indicate greater reductions of the functionality level (i.e., a lower resistance (or a lower robustness) of the road network in the event of a disruptive event).