诱导条件下的路网交通过饱和预防性控制

Preventive signal control for over-saturated road network under traffic guidance

为预防路网局部过度拥堵导致路网大面积过饱和,分析了路段和路网的过饱和交通状态,提出路网过饱和状态判定及过饱和诱导控制策略启动时机的判定方法;基于有向图论,在固定交通需求条件下,以路段饱和度最大值最小化为目标,路段通行能力和路段流量平衡为主要约束条件,建立了交通诱导模型;以路段饱和度方差最小化为目标,路段通行能力和相位时长调整的极限值为约束条件,建立了交通控制模型;采用遗传算法进行求解。算例路网的试验对比表明,交通诱导使路网过饱和路段的最大饱和度有所降低,降低了19.6%;交通控制模型使各路段的饱和度均衡,标准差也有一定程度的降低,降低了12.9%;表明在交通诱导和控制协同管理下,路网运行指标有所改善,在一定程度上预能防路网过饱和状态发生。

In order to prevent congestion of local road network which often leads to large scale road network over-saturation,the over-saturation states of road sections and road network were analyzed,and the method of road network over-saturation judgment and the method of ripe time judgment to trigger the guidance and control strategy were proposed.Based on graphic theory,the traffic guidance model was established under fixed traffic demand,taking the maximum saturation minimization as the objective,capacity and link flow balance as constraints.Traffic control model was established taking the link saturation variance minimization as the objective and link capacity and maximum phase time incremental as constraints.The models were solved by use of Genetic Algorithm.The experiments on case road network reveal that traffic guidance leads to reduction of maximum link oversaturation by 19.6%,and traffic control model leads to equilibrium of the saturation of each link the reduction of variation by 12.9%.As a result,the collaborationof traffic guidance and traffic control can significantly improve the performance of road network.To certain extent,the model can prevent large scale oversaturation and congestion of road network.7tabs,3figs,24 refs.