# Evaluation of Subway Emergency Evacuation Based on Combined Theoretical and Simulation Methods
## 4 Results and Discussion
### Evaluation of Emergency Evacuation Capacity for Scenario #3  
This scenario posits the simultaneous arrival of four trains, each at maximum capacity, at the platforms of Line #1 and Line #4. Consequently, both platforms reach their full capacity upon the arrival of the trains. The population within the station hall remains constant throughout this event. All sections of the subway station experience peak passenger flow, thereby simulating conditions of extreme congestion. Specifically, the Line #4 platform accommodates 285 passengers, while the Line #1 platform accommodates 282 passengers. Each train has a maximum capacity of 720 individuals. The non-paid area of the concourse can hold 338 individuals, whereas the paid area has a capacity of 269 individuals. In total, the number of evacuees is recorded at 4054 individuals. Figure 15 illustrates the variation in passenger numbers across different areas under Scenario #3. The analysis reveals that the duration required to evacuate passengers from the carriages of the four trains to the platform is nearly uniform. This suggests that the evacuation of train carriages does not constitute a significant issue within the overall emergency evacuation process. At 28 s, passenger flow on the Line #1 platform peaks at 1402 individuals, while at 27 s, the Line #4 platform experiences a peak of 1249 individuals. The higher passenger count on the Line #1 platform can be attributed to the proximity of passengers from Line #4 to the transfer stars. Furthermore, the overall increase in passenger flow results in a greater number of individuals in the paid area of the station hall compared to the non-paid area. This phenomenon is primarily due to congestion at the fare gates, which emerges as a critical factor contributing to extended evacuation times. Figure 16 depicts the fluctuations in the number of passengers utilizing stairs and escalators in Scenario #3. In comparison to Scenario #1, there has been an enhancement in the overall evacuation efficiency of the four staircases. During the evacuation process, the cumulative evacuation totals for the left side of Staircase C and the left side of Staircase D reach peaks of 474 and 478, respectively. The flow of passengers is observed to range from 1.5 to 2.5 individuals per second, with the utilization rate reaching its maximum. This occurrence can be explained by the fact that, at this stage, passengers from the Line #4 platform are able to access the Line #1 platform through the interchange station. Consistent with the principle of proximity, passengers exhibit a preference for the staircases that are closest to them, particularly the left side of Staircase C and Staircase D.  
Figure 14: The utilization status of different exits under Scenario #2. Figure 17 illustrates the utilization status of the various exits. The passenger flow rate at Exit A ranges from three to five individuals per second, demonstrating a consistently high level of passenger movement throughout the evacuation process. The total number of evacuees ultimately reaches 1180. The simulation indicates that significant congestion occurs near the gates adjacent to Exit A. Exits B, C, and G also display elevated utilization rates, with cumulative evacuation counts of 686, 829, and 746 passengers, respectively. In contrast, Exits E and F exhibit the lowest utilization rates, with cumulative evacuation counts of 163 and 23 passengers, respectively. Within the designated timeframe, these exits reach their maximum capacity, and after 60 s, there is no further passenger flow through Exits E and F. Therefore, it is recommended that attendants be deployed to direct passengers toward Exits E and F, as this could facilitate a more efficient evacuation process. Figure 16: The variation in the number of passengers on stairs and escalators under Scenario #3. Figure 15: The variation in the number of passengers in different areas under Scenario #3.