Simulation and optimization of pedestrian evacuation in high-density urban areas for effectiveness improvement

Rapid urbanization has made many cities in China enter an era that increment and stock develop in parallel. Urban central area presents the characteristics of complex spatial structure and high functional complexity, resulting in the huge disaster risks and severe security issues of evacuation. This paper proposes a method of improving emergency evacuation effectiveness under the restriction of limited available land resources in high-density areas, which is combined with urban renewal planning, aiming at optimizing the layout of shelters and evacuation passageway by cyclic evacuation simulation, evaluation and optimization with Anylogic software and facility location tool based on ArcGIS. Taking the renewal planning of Jintang Road Area in Tianjin, a typical high-density urban area, as a case study. The results showed that: 1) The evacuation space system of Jintang Road Area exists potential danger that severe congestion occurred in the simulation process and the congested section spread outward with three shelters as the center. Which lasted for several hours. The rate of successful asylum in 5 min and 30 min was 13% and 34%; 2) The matching degree between spatial layout of emergency shelters and population distribution is low, which is reflected in the utilization rate of shelter: the rate of shelter No.1 is as high as 826%, while that of No 4 and No 5 is 48% and 11%, and also causes unreasonable distribution of people flow in evacuation passages during the evacuation process; 3) The research method of integrating simulation, facility location and renewal planning is an effective way to improve the effectiveness of pedestrian evacuation in high-density urban areas. After the improvement, the four indexes have been effectively improved.