基于防灾的城市地下空间网络复合可达性评价

Evaluation of the Composite Accessibility of Underground Space Network from the Perspective of Disaster Prevention

随着我国城市化不断推进,城市中心区的高密度化非常突出,在全球化灾害多发的背景下,城市高密度地区的易损性显著,应充分利用其立体化空间特别是地下空间的防灾特性提高城市韧性。本文针对地下空间网络在灾时可以作为避难疏散通道的功能特点,提出了高密度地区地下空间网络的复合可达性评价框架,结合避难行为特点提出了地下空间网络的全局可达性、交通枢纽可达性、地面防灾空间可达性三个指标,并进一步基于图论给出了地下空间网络的建模和计算方法。选取了南京新街口和广州珠江新城分别作为老城区和新城区典型高密度地区,以其地下空间网络为例进行了计算和分析,并给出了相应的规划对策和建议。

With the development of urbanization in China,the local high density state is gradually formed in the construction of cities,and the fragility of urban high-density areas is obvious in the context of the multiple disasters of globalization,it should be strengthened that construction of disaster prevention and mitigation by using its stereoscopic space. In view of the functional characteristics of the underground space network as an evacuation channel in the event of disaster,this paper proposes topological analysis of underground space network based on computational and functional graph representations,and various graph measures,including connectivity,closeness centrality,and network efficiency,are computed for structural analysis. Based on validations applied to two typical high-density areas in Nanjing Xinjiekou and Guangzhou Zhujiang New Town, the empirical analysis was carried out, and the corresponding planning countermeasures and suggestions were proposed.