The Calculation Of Network Capacity And Analysis Of Improving Under The Influence Of Constructing Urban Road

With the increasing number of motor vehicles,the urban road network capacity can no longer be loaded,traffic congestion is becoming more and more serious,and the contradiction between the traffic environment and urban construction is gradually emerging.In such a trend,it has a great significance to grasp the traffic characteristics of work zone,accurately calculate the network capacity and improve network capacity from the traffic organization.In this paper,the research on the capacity and improvement of the urban construction road network is carried out under such a background.First,study the traffic impact of the work zone to the road sections in the area,ananlyze the traffic,personnel and vehicle characteristics under the impact of this situation.Study the network capacity,service level and traffic organization are influenced by work zone.It lays the foundation for the study of network capacity and traffic organization within the impacting area of work zone.Secondly,according to the equivalent capacity of the road section,the scope of the work zone influencing area is determined.Considering the characteristics of construction,from the perspective of consuming time-space,the traditional "time-space consume model " is improved by analyzing seven factors that affect the network capacity.Use the "Cloud model" to analyze the different influences of the work zone on different locations,and calculate the road network capacity of different levels of the area.Finally,the model calculation process is given.Furthermore,this paper builds a identificating key roads model,the purpose is to implement targeted traffic organization to increase the network capacity.Vulnerability is used to define the key road section,and the criticality of the road section is regarded as the product of the road section failure probability and the road section failure consequence.Innovatively introduces the failure probability model of the road section under the constructing road network.Based on the network topology structure diagram and the pre-loaded traffic distribution method,the network efficiency change rate and the travel time change rate are calculated to jointly evaluate the road failure consequences.Finally,based on the research on the traffic impact and traffic characteristics under the work zone influencing area,we explore the optimization methods of the traffic organization from three aspects: "point-line-area".And analyze the traffic flow diversion methods,including setting node and determinating organization network.And the proposed method is used to design the transportation organization plan,and the VISSIM simulation is used to evaluate whether the transportation organization plan is reasonable.Applying the research results of this paper to the construction road network of Qujiang Datang Everbright City,on the one hand,it can prove that the research method has certain practical value,on the other hand,it can guide city managers to formulate transportation policies,and can be a reference template to the control and organize traffic.