Study On Regional Optimal Traffic Capacity Oriented To Demand Control

With the rapid advancement of China's urbanization,motorization and modernization process,the city's traffic supply is gradually unable to meet the rapid growth of urban traffic demand,and traffic congestion is becoming more and more serious.This is a common phenomenon caused by the imbalance between supply and demand.The increasing contradiction between transportation demand and transportation supply will lead to congestion.To alleviate traffic congestion,it is not enough to increase traffic supply.Only by effectively controlling traffic demand can the contradiction between supply and demand be fundamentally resolved.For a regional road network,when the traffic demand is calculated by calculation,the vehicles in the region can reach the optimal operating state,which can provide important technical support for urban traffic control.Based on this,this article carefully analyzes and studies the regional optimal traffic capacity and establishes the regional optimal traffic capacity model.The specific contents include the following aspects.First,consider the influence of multiple factors to establish the optimal capacity model of the road section.By analyzing the influence of factors such as lane width,proportion of large and medium vehicles,and access to branch roads on the capacity of bicycle road segments,the optimal capacity model of bicycle road segments is established,and based on this,vehicle lane change,temporary parking,and bus stop station settings are considered.Factors such as form and pedestrian non-motorized vehicles have established a multi-vehicle road capacity and its correction coefficient calculation model,and completed the establishment of a multi-car road segment optimal capacity model based on the Greenhill governance model.Secondly,consider the factors of lane channelization and signal control based on road sections to establish the optimal capacity model of the intersection.Taking the lane group as the research object,the impact coefficients of different steering traffic ratios in the case of lefthanded protection phase and right-turned control are determined respectively,and the capacity calculation of the intersection group under four different combinations is established.The model determines the optimal flow and speed when the intersection is at the optimal road network capacity,provides data support for the traffic constraints of the intersection between road networks,and provides a theoretical basis for calculating regional road network capacity later.Thirdly,by analyzing the flow restriction between adjacent intersections in the area,the optimal traffic capacity model of the regional road network is established.According to the principle of area division,the complex road network is divided into several sub-areas,and the reference intersection is selected in each sub-area to make it reach the optimal capacity.Then through the mutual restraint between the sub-regional intersections,the traffic conditions of other intersections in the region are obtained,and finally the establishment of the regional optimal capacity model is completed.Finally,by selecting a regional road network in Hunnan District of Shenyang City,the above model was simulated and verified.Combined with the best road network calculation model proposed in this paper,the optimal road network capacity is calculated for the actual road network,and the two parameters of delay and service level are selected for simulation verification using VISSIM simulation software,and the road network proposed in this paper the calculation model is feasible.