在发生地震等特大事件时,一条或多条路段可能完全丧失其功能,路网、起讫点对(OD对)之间是否连通成为最关键的问题.根据网络的拓扑结构来研究路网承受异常事件的能力.将通信领域内提出的最小割频度向量的指标引入路网拓扑脆弱性评价中,该指标对不同的网络具有可比性,能反映路网结构特征,并且能考虑路段本身承受灾害能力的差异对拓扑脆弱性的影响.给出网络拓扑脆弱性指标定义及计算方法,并用示例路网进行演算,结果表明该指标具有可比性和有效性.利用该指标对路网上的关键路段进行分析,并通过在指标计算中考虑路段抗灾害能力来评价路段抗灾害能力提高后拓扑脆弱性的改善效果.
When catastrophic incidents such as earthquake happen,one or several links may lose its (their) functions totally.Then whether the network and origin-destination(OD) pairs are still connected becomes the most critical problem.Therefore,this paper presents a study of the road networks’ abilities to undergo incidents from the point of view of its topology.The assessment index “mincuts frequency vector” prevailing in the field of telecommunication is intreduced into the assessment of topology vulnerability of road network.Since this index is comparable between different networks,it can reveal the structure characteristics with a consideration of the difference of links’ abilities to undergo incidents.The definition and algorithm of the index are described by trial networks.The results are then used for the identification of critical links.With consideration of the links’ abilities to undergo the incidents,the index is adopted to evaluate the effect of improving critical links.