Research On Model And Method Of Road Network Coordination Path Set Optimization And Regional Green Wave Coordination Control

With the rapid expansion of modern urban road network,the supply of urban roads can no longer meet the needs of urban development,the capacity of urban roads has gradually become saturated,and road construction has entered the "end".Therefore,more effective urban intersection management and control methods are needed to meet the needs of urban development.In this regard,this paper conducts research on the model and method of road network coordination path set optimization and regional green wave coordination control.The main scientific research work and research results obtained are summarized as follows:1)The theory of traffic coordination control for urban road network is analyzed.The minimum coordination control unit segment is refined into a coordination path,and the relationship between the traffic flows in the coordination path is studied.A path coordination degree calculation model for the coordination path is established.The judgment conditions for the selection of coordination path are given.The selection principle of regional coordination path set is studied.The optimization method of coordination path set based on the degree of coordination of the path is studied.An example is used to verify the feasibility of the proposed optimization method,which lays a theoretical foundation for the determination of coordination objects.2)Considering the shortcomings of the existing two-dimensional time-space diagram which shows the coordination effect in the application of regional coordination control,an innovative three-dimensional time-space diagram analysis method for regional green wave coordination control is proposed,which realizes the three-dimensional description of the spacetime relationship between intersections in the road network.It breaks through the display effect of the traditional time-distance map based on two-dimensional plane,and reflects the green wave band generation effect of multiple north-south arteries and east-west arteries in the area from the perspective of three-dimensional space.The overall green wave coordinated control effect of the regional traffic signal coordinated control scheme was fully displayed,and the advantages and disadvantages of regional traffic signal coordinated control effect were demonstrated,and the regional coordinated control effect was more intuitively displayed.3)Considering the intersection using the Ring-and-Barrier structure phase mode,the constraint relationship between signal timing parameters such as signal cycle,phase phase sequence,and phase time is studied.Taking each traffic flow of intersection as research object.A regional green wave coordinated control optimization model suitable for the Ring-andBarrier structure under unsaturated traffic conditions was established,which can meet the minimum traffic demand of each traffic flow at each intersection and make the entire area have a good coordinated control effect.By increasing the phase time dimension in the signal optimization space,the overall optimization effect of the regional signal coordinated control is improved,thereby realizing the optimization of the signal cycle,phase sequence,phase offset,and phase time in the region.The calculation results of the case show that the timing scheme obtained by the model in this chapter has comprehensively optimized the phase time and phase sequence of each intersection,which makes all intersections obtain a larger proportion of bandwidth,indicating that the overall regional coordinated control effect is very obvious.4)According to the characteristics of the direction and asymmetry of the coordination control demand in the road network,the coordination path is taken as the minimum control unit segment in the green wave coordination design,and phase time,phase center point,phase offset and common signal cycle of each intersection are taken as the optimization variables,and taking each phase of the intersection as research object to establish a regional green wave coordination control optimization model for the coordination path,which realizes the organic unification of different types of control variables,such as intersection phase time,signal phase sequence,phase difference,etc.And the comprehensive optimization of regional signal timing parameters is completed.The case analysis shows that the model in this chapter can be applied not only to the design of green wave coordinated control of cross artries in the region,but also to the design of regional green wave coordinated control for coordinated path.The best signal timing design schemes obtained by the model in this chapter all have large regional green wave band widths,indicating that the models in this chapter can ensure the overall regional green wave coordinated control effect,which shows the model has wide applicability.