基于循环疏散分配的避难场所布局优化研究——以南京新街口为例

Optimization of Shelter Location in High-Density Urban Area based on Circular Evacuation Allocation:a Case Study in Xin Jiekou District of Nanjing,China

如何在城市高密度地区合理配置避难场所,提高居民避难疏散的效率,已成为城市发展面临的重要问题。基于传统避难场所布局优化研究在避难需求预测、疏散分配方面的不足,提出了基于循环疏散分配的两阶段避难场所布局优化方法。首先基于手机信令数据获取高精度昼夜避难需求。优化模型设计了基于重力模型的循环疏散分配规则,同时考虑避难人群年龄结构的空间差异性,以避难场所建设成本和总疏散距离为目标函数确定最优的避难场所布局方案。第一阶段以避难场所建设成本最小为优化目标,设计遗传算法确定建设成本最小的布局方案。第二阶段以总疏散距离为优化目标,在第一阶段的基础上采用穷举法确定总疏散距离最短的避难场所布局方案。以南京市新街口片区为实证研究案例,验证了基于循环疏散分配的避难场所布局优化方法的可行性和适用性。

High-density urban area is a kind of area with high population density,complex spatial structure and high composite function.Reasonable shelter location to satisfy the refuge demand of all residents and improving the evacuation efficiency has become an important issue for urban disaster prevention.Based on inadequacies on evacuation demand calculation and evacuation allocation of traditional methodology,a two-stage shelter location optimization method based on circular evacuation distribution is proposed in this study.Firstly,the high accurate evacuation demands are determined through cellular signaling data.The“circular evacuation allocation rule”proposed in this study is established based on gravity model.The impact of age structure of residents on evacuation process is considered.The optimization model takes the construction cost of shelters and the total evacuation distance as objective functions under the limitation of shelter capacity and maximal evacuation distance.In the first stage,the minimum construction cost of shelters are taken as the optimization objective.The genetic algorithm is adopted to determine the minimum construction cost of shelters.In the second stage,the objective function is the total evacuation distance.On the basis of the first stage,the optimal shelter location scheme with the shortest total evacuation distance is determined by exhaustive method.This study takes Xin Jiekou district in Nanjing as an empirical case to verify the feasibility and applicability of the shelter location optimization method based on circular evacuation allocation.