Introduction. The expediency of using the main traffic flow diagrams as the basis of transport modeling is substantiated and the sequence of calculations of traffic flow parameters for construction of the diagram in the form of traffic flow dependences is determined.
Issue Statement. The research of well-known specialists in the field of mathematical modeling of road traffic, who continue to work intensively in this direction, is described. It is proved that the problem of pre-traffic congestion and traffic congestion modes has not been fully studied and is the base for traffic management in large cities [1–2].
The selection of the control technology type depends on the task and purpose of traffic management. The analysis of mathematical support of world-famous control systems [3] showed that it is based on the implementation of macro and micro models of interdependence of the main parameters of the traffic flow and the parameters of movement of individual vehicles.
The basis of traffic flow modeling are macro and micromodels: the first macroscopic models (hydrodynamic), in which the traffic flow is considered similar to the flow of compressible fluid (M. Lighthill and J. Wisem, P. Richards (LWR)) [4] and the first microscopic models (following by the leader), which describe the movement of each car (A. Rochelle, L. Pines) [5].
Purpose. Improving the efficiency of the street and road city network operation by determining the balance between road traffic parameters. Determination of places of congestion occurrence by hydrodynamic model and dependences of traffic flow.
Materials and methods. The main dependences of the traffic flow taking into account the number of traffic lanes are given. According to the method of hydrodynamic model, the places where congestion can be occurred are calculated and determined. The main dependences of the traffic flow are graphically shown. The method of comparison and identification shows how the density, intensity and speed will be changed depending on the change in the number of traffic lanes.
The places where congestion can be occurred are calculated and determined using the method of hydrodynamic model. The main dependences of the traffic flow, the change in the density, intensity and speed depending on the change in the number of traffic lanes are graphically shown.
Results. The intensity is varied depending on the traffic speed. The higher is the speed, the lower is the intensity. From the dependence «Intensity – density» it is seen that the bigger is the intensity, the lower is the traffic flow density. From the dependence «Density – traffic queue length» it follows that the bigger is the density of the traffic flow, the greater is the length of the traffic queue.
Conclusions. Since congestion occurs when there are "bottlenecks" in the transport network, therefore, traffic management in a forced mode, in the first place, should be aimed at creating such traffic conditions that meet the restrictions for all the road sections located between the intersections in the road network.
Congestion concentrated within a small area affects other traffic flows and if the traffic volume exceeds the road capacity, the congestion spreads over long distances. To avoid this situation, it is necessary to disperse traffic jams in order to reduce the impact on other traffic flows.
