Urbocongestion or overload of the urban transport systems

Анотація

Problem. A new state of prolonged congestion in large cities, megapolises, defined in global practice as traffic congestion, is discussed to determine the conceptual foundations and guidelines needed to manage congestion in order to reduce its overall impact on individuals, families, communities and the urban community as a whole. Urban Traffic status is ongestions, i.e., overflowing streets and roads and, as a result, slow congestion column traffic. Goal. The task of traffic management is to reduce the level of saturation by methods of increasing the capacity of streets and roads in the city is considered. Methodology. Methods of town-planning science are involved in the development of appropriate criteria for evaluating the state of the congestion and allowing to manage the diversity of these states. The very concept of a congestion is considered in detail. First of all, it is a physical phenomenon related to the state in which vehicles hinder each other’s movement, and it is also a relative phenomenon related to the work of the whole system. Results. Congestion is a situation in which the demand for road space exceeds supply.  There are two properties that define the saturation properties of roads. The first is when vehicles impose restrictions by moving one after the other.  The second property is contained in the concept of "speed flow relationship". This concept served as a basis for understanding of congestion mechanics, formation of queues and defined the most operative answers to the problem. Originality. Scientific novelty is the use of the new "generalized intensity", characteristic of the transport flow, in which the velocity of the flow V(t) is a clear function of the rate of change in intensity dN(t) /dt, V = C dN(t) /dt where the characteristic C of the transport flow takes into account the rate of reduction or increase in the distance between cars, i.e. the rate of change in speed when the intensity of the transport flow changes.  The dependence of N(t) on V(t) is established in the explicit form. Variables are replaced by introducing a new variable L(t) as a generalized pathway.  The equation for the variation with respect to N(t)=0, L(t)=CN(t) is obtained. The inverse of the intensity which is called the specific intensity of the traffic flow - U (aut/h.km) - is analyzed, which shows how the intensity is distributed on the road section. The specific intensity of the U increases in proportion to the normal intensity, and is propagated when the flow is compressed. The dimension U corresponds to the dimension of the continuity equation. The conclusions indicate the ways to reduce congestion (tension) and recommend that this factor be taken into account when solving urban transport problems.