Influence of a carriageway width on the car Speed under urban conditions

Abstract

Problem. The car speed is the most important indicator of the traffic organization level. A priori it is obvious that the value of the car speed in a particular place and at a particular time is random. The randomness of speed is due to the influence on it of too many factors that cannot be taken into account analytically - from the driving style of each driver, which in itself is made up of individual actions, which are difficult to predict, to a large number and individual behavior of other road users. Establishing a car speed distribution in various conditions is an urgent task, whose solution is the basis for improving the accuracy of traffic forecasts that are formed us-ing analytical or simulation models of transport net-works and their elements. Goal. The goal is obtain-ing patterns of changes in the car speed in limited road conditions, with the narrow carriageway. Methodology. The methods include development of a valid hypothesis regarding the type of distribution of the car speed in limited road conditions and its ex-perimental verification using the example of an ur-ban street with parked cars. Results. The hypothesis about the possibility of using gamma distribution to describe the car speed in any driving conditions, i.e. for any average car speed, was not denied by exper-imental observations of the movement of vehicles on a narrow section of the urban street 5.45 m wide for two directions. Originality. New hypothesis was promoted and tested about the kind of car speed distribution, not in free, but in limited road conditions. Practical value. The obtained result is the basis for improving the accuracy of traffic forecasts that are formed using analytical or simulation models of transport networks and their elements in transport consulting.

Keywords

• road lane width
• car speed
• urban street
• random variable
• gamma distribution