Study On Theory And Methodology Of Planning And Design Of The Node Of Urban Roads

The node of urban roads is the important component part of urban road networks. It is the bottleneck of urban road traffic. Its setting reasonability concerns the traffic function performance of relevant roads or even of the whole road network. It has great influence on city mobility, road capacity, capacity of road network and traffic safety. For seeking the effective way to solve the urban road traffic problem, theory and methodology of planning and design of the node of urban roads were tried to be researched through studying its primary characteristics.Compared with the urban road segment, the urban road node has many different traffic characteristics. Some of them exist naturally at nodes, but they are accident on segments. It is very important to know, to understand and to grasp traffic characteristics of urban road nodes for research on it and its planning and design. Eight kinds of characteristics of urban road nodes were summarized and analyzed. These characteristics include traffic flows'arriving at multi-distributing, arriving traffic volume varying in periods, turn demand of arriving vehicles , velocity varying, stopping and waiting, traffic conflict, time delay and bottleneck.The urban road is overground traffic facility which lies in the city with network form. Because of the different function of roads and the difference of region, the form of intersections and connections between them is different with each other. At present, the types of nodes adopted in China and abroad include uncontrolled intersections, all-way stop-controlled intersections, two-way stop-controlled intersections, signalized intersections, roundabouts, grade-separated junctions and their combinations. Each type of nodes has different characteristics and adapts to different function demands.Nothing can be accomplished without norms or standards. The modern urban road traffic system is an ordered system. This kind of order is set up by unified traffic rules and is guaranteed by laws. The importance of the right-of-way rules at the node is determined by the characteristic of the urban road node. The right-of-way rules of ours and others were studied contrastively. The concept of right of way was defined. Eight basic principles for sharing the right of way and constituting its clause were...