The problem of the change in the speed of traffic flow at different traffic volumes and compositions is researched in this study. The section of the road network with different geometric parameters (descent, ascent and horizontal section) was chosen for the study. The method of investigation of traffic flow`s speed and factors which have an impact on the reduction of road network capacity are analyzed.
The problem of capacity increasing of arterial streets with controlled motion is investigated in this paper. For investigation, sections between intersections on the road network of Lviv city were chosen at their different length and roadway width with most saturated traffic. Methods of capacity increasing of arterial streets with controlled motion and factors that have impact on the capacity reduction are analyzed. Capacity of intersections at different volume-capacity ratios is determined. The distribution of average speed for sections between intersections of different length is built.