道路交通网络脆弱性动态辨识方法

分析了路段和节点的流量传播过程与离散的瞬时动态用户最优路径选择均衡条件, 建立了反应型的动态用户均衡网络交通流模型, 设计了对角化的启发式算法求解模型, 评价了动态化的道路网络脆弱性指数。分析结果表明: 在自由流速度为40km·h^-1、堵塞密度为125veh·km^-1的9节点12路段构成的算例路网中, 在时刻3路段1受损时, 路段3在高峰时的车辆数量从原有的50veh增加到了100veh, 入口流量增加1倍, 路段2的入口流量降为0;在路段3、6、7和10构成的路径上, 路段1受损使得此路径的车辆数将近增加1倍, 车辆数量的增加导致各路段的阻抗增加。提出的方法能刻画车辆绕开受损路段的交通流传播过程, 能有效辨识道路网络在各个路段各个时刻的脆弱性。

Identification method of dynamic road traffic network vulnerability

The trfffc flow propagation process of section and node and the discrete instantaneous dynamic equilibrium condition of optimal route choice for user were analyzed, the reactive traffic flow model of dynamic user equilibrium network was established, diagonalizable heuristic algorithm was designed to solve the model, and the dynamic vulnerability index of road network was evaluated.Analysis result shows for an example road network with 12 sections and 9 nodes, free-flow speed is 40 km·h-1 and jam density is 125 veh·km-1, when section 1 is broken at time 3, vehicle amount at peak time increases from the original 50 veh to 100 veh at section 3, the inflow of section 3 increases by 1 time, and the inflow of section 2 drops to 0.The damage of section 1 doubles the vehicles on the path consisting of sections 3, 6, 7 and 10, the increase of vehicle amount leads to the increase of impedance on each section.The traffic flow propagation process of vehicle bypassing the broken section can be described, the proposed method is effective to identify the vulnerability of road network for each section at each time.