基于OD反推的城市路网脆弱性评价

摘要

交叉口是城市道路网络中的瓶颈部分,对交通流的运行存在着很大的影响,但在以往的脆弱性研究中忽略了交叉口对于交通流运行的影响.在考虑了交叉口处交通流运行受到的影响后,改进了传统的级联失效模型;然后采用OD反推的方法在路网单元失效后的局部影响范围内进行交通需求重构;最后以交通流路段总行程时间和交叉口处总服务时间的变化构建综合指标来评价城市道路的脆弱性.实例分析结果表明:所提出的改进的级联失效模型和脆弱性计算指标,都有助于提高路网脆弱性的计算精度.%Intersection is the bottleneck part of city road network,and there is a great influence on the traffic flow running. But the vulnerability of the former research ignores the influence of intersection for the traffic flow. Traditional cascading failure model is improved by considering the influence of intersection,and the traffic demand is reconstructed through OD matrix estimation method within the scope of the local effect. The change of the total link travel time and the change of the total intersection service time constitutes are combined into a new comprehensive index to evaluate the vulnerability. A case study is conducted to illustrate the approach,and the results show that the improved cascading failure model and vulnerability index are helpful to improve the calculation precision of network vulnerability.