Location Of The GIS-based Primary And Secondary Evacuation Site

At present, the security problems of primary and secondary school students, has become a significant problem related to the individual life and social development. This paper selected the primary and secondary school of Xicheng District in Beijing as example to propose an optimal evacuation model for primary and secondary school’s emergency shelter. This paper mainly discussed three issues:(1) Analysis of the environmental constraints factors and influenced scopeStarting from security and suitability of emergency shelter, flammable and explosive site, collapsed range of High-rise buildings, rivers and lakes, terrain slope, earthquake fault zone, and protection range of cultural relics were selected in this analysis. Based on buffer and overlay analysis with GIS technology, the environmental constraints model had been made to predict the influenced scope for selecting the high safety and good suitability school emergency shelter.(2) Combination of the evacuation demand and the site supply with GISConsidered the influence of environmental constraints factors, the evacuation demand and the site supply was used with GIS. There are115primary and secondary schools in Xicheng District, which have the completed data. After analysis of these data, the result showed that67primary and secondary schools’ playgrounds had the remaining capacity,48primary and secondary schools didn’t have the enough capacity for students to evacuate. The green space, park, car park, square around schools had been selected as alternative evacuation sites. Under the influence of environmental constraints, the maximum evacuation capacity of these sites was calculated.(3) Focus on the analysis of primary and secondary school’s emergency shelterThe alternative evacuation sites which could offer the evacuation service were selected by using the500meters buffer. It was found that these sites are consisted of426alternative evacuation site and17primary and secondary schools’ playgrounds which had the remaining capacity. By using the network analysis of unaffected road, the shortest evacuation road was found between these primary and secondary schools and alternative evacuation sites. Based on the location-allocation model theory, uniting the primary and secondary schools, alternative evacuation sites, and evacuation road completely, an optimal evacuation model for the primary and secondary school’s emergency shelter location selection was made with constrains of the largest site service capacity and the shortest network distance. By using this model, the72influenced predetermined emergency shelters and72evacuation roads were obtained. Considering the influence of environmental constraints, by using the Voronoi diagram, the Euclidean distance method, the influenced evacuation road was solved to improve the use of predetermined evacuation sites. Ultimately the primary and secondary school’s emergency shelter location was selected to protect the student who in the insufficient evacuation capacity school from the disaster.In this paper, the method of primary and secondary school’s emergency shelter location was applied in Xicheng District, Beijing City. The regression equation model was made to get the collapsed range of High-rise buildings. This method which was used in the research field of evacuation site selecting had certain innovation. It laid a safety basis for shelter school location. By using the network analysis of actual road, and fully considering the relationship of the evacuation demand and the site supply, the optimal evacuation model had been improved to ensure the applicability of primary and secondary school’s emergency shelter location.