Research on traffic flow speed of arterial streets in urban areas

Abstract

Road traffic flow intensity is growing up in Latvia. To address increasing traffic intensity, there is a need for new arterials in urban areas, but then, of course, require additional infrastructure space. However it is known that the construction of arterials in urban areas, compared to a lower category of street construction, is very expensive. The high costs include not only the construction of arterials, but also the land redemption, demolition of buildings, businesses moving to other areas issues. In order to reduce the above costs, there is a need to evaluate all possible ways to reduce the total costs of construction of arterials that first of all can be achieved by reducing geometrical parameters of arterials. The street design parameter reduction, such as travel longitudinal profile of the radius of curvature, plane curve radius of carriageway lane widths, etc., is a compromise resolution. The arterial streets’ parameters can be reduced first of all by changing the design speed. The study makes the correlations between the momentary speed of the continuity of service orientated city conditions and the maximum permitted speed, design speed, traffic flow density and loading ratio. Authors have found the relationship between design speed and momentary speed for different traffic densities on arterial streets. Further efforts are needed in developing recommendations for the design speed of numerical values.