摘要
协调优化城市各等级道路系统,能有效促进其网络结构与资源的共享、合作与互补。文章在对快速路通道系统研究现状及已有优化理论方法分析的基础上,研究城市快速路出口匝道与周边路网衔接区域交通"瓶颈"产生的原因,以"交通压力均分、负荷转移"思想,建立以辅路分流为上层模型、以用户均衡分配为下层模型的双层规划模型,在模型中考虑了分流车辆绕行延误、交织延误以及受影响车辆运行延误等因素,最后给出算例。结果表明:优化后路网衔接区域交通"瓶颈"拥堵状况得到缓解,系统总延误大大降低,路网平均总延误相对不分流情况减少61%,相对固定分流情况减少50.1%;通过优化模型可获得辅路最优分流比例,结合算例,得出当出口匝道与辅路交通需求量为1500 pcu,且周边路网车道具有足够剩余通行能力时,其辅路分流比例可达0.9以上;当出口匝道及辅路交通需求超过1500 pcu,且受周边路网通行能力限制时,辅路分流比例随着辅路交通量与匝道交通量的增大而减小。
The coordinated optimization of each grade road system can effectively facilitate the sharing,cooperation and complement of the network structure and resources.On the basis of analyzing research status and existing optimization theoretical method of expressway tunnel system,this paper researches the reasons for the connection regional traffic ＂ bottleneck＂ between urban expressway offramp and surrounding road network,establishes a bi-level programming model of the upper model for side road traffic diversion and the lower model for user equilibrium assignment,which is based on the thought of ＂ divide traffic pressure,load transfer＂.The model considers some factors such as routing delay of distributed vehicles,interleaving delay and running delay of effected vehicles,and also gives a numeric example.The results show that the congestion of connection area traffic ＂bottleneck＂ is relaxed and the total system delay decreases substantially in the optimized-network,the average total delay of road network decreases significantly and its relatively non shunt decreases by 61%,and its relatively fixed shunt decreases by 50.1%.According to the proposed model,we can obtain the optimal diversion ration of auxiliary road.Finally,by combining the numeric example,the optimal diversion ration of auxiliary road can reach more than 0.9 when the off-ramp and side road traffic demand is 1500 pcu,and the sun-ounding road network lanes with sufficiently surplus capacity.When the traffic demand of off-ramp and side road surpasses 1500 pcu and restricted by the surrounding road network capacity,the auxiliary road diversion ration decreases with the increase of auxiliary road and off-ramp traffic volume.
出处
《山东建筑大学学报》
2017年第1期33-38,共6页
Journal of Shandong Jianzhu University
基金
国家自然科学基金资助项目(71171124
71371026
71471104)
关键词
城市快速路
出口匝道
路网
双层规划
辅路分流
urban expressway
off-ramp
road network
bi-level programming
auxiliary road diversion
