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随着机动车保有量的增长，交通拥堵已成为大城市普遍面临的问题.交叉口是城市路网的节点，也常常成为了城市路网的瓶颈点.如何减少车辆在交叉口的延误是提高整个路网运行效率的关键.本文对北京市一典型交叉口的交通问题进行了分析，针对减少机非冲突保障安全、降低延误保障畅通等方面提出了相应的管理方案，利用微观仿真技术对交通管理方案进行了定量的评估分析和优选.仿真计算结果显示，四个改进措施从不同方面有针对性地缓解了交叉口的冲突、降低了机动车的延误.

Traffic Organization Optimization of Changhongqiao through Microscopic Simulation

With sharp growth of motor vehicle ownership,traffic congestion has become a common problem in metropolitans.However,intersections,the nodes of the urban road network,are always regarded as the bottlenecks of the network.Reducing traffic delays in intersections is the key to improve the total operation efficiency of road network.This paper conducts a case study of the intersection traffic problems in Beijing.Some management schemes are proposed to improve the safety caused by traffic conflicts and to reduce delays at the intersections.With microscopic simulations,the schemes are evaluated and selected quantificationally.The simulation identifies four improvement measures perform well in alleviating the conflicts in intersections and reducing the vehicle delay from the different ways.