Study of Optimized Evacuation Route of Commercial Street Based on Microscopic Model

In the microscopic evacuation model, the desired direction of the pedestrian is consistent with the minimum-distance route. However, the minimum-distance route may not be the same as the minimum-time route. In fact, the individual evacuation time is not only related to the distance but also the pedestrian distribution and exit width. In this paper, the evacuation route optimization algorithm is presented based on the microscopic model. In order to attain the optimal evacuation route, the iterative method is used for solving the optimal exit choices for each pedestrian. Taking a commercial street as an example, the classical biased-random walk model without back-step is applied to simulate the evacuation process, and the evacuation time with optimized and non-optimized evacuation route are compared and analyzed. The algorithm solves the shortest minimum time from the global perspective. The results show that under the influence of the optimized route, some people no longer choose the nearest exit but the exit with larger width or with lower occupant density around. The exit selection zone map from the results can provide the placement of guiders and the guiding direction to the designer. In application, the guiders can suggest the evacuee to choose an optimal exit to help them evacuate more quickly.