Roundabout the basic element of modern road infrastructure and traffic

Abstract: The use of roundabout intersections, regardless of the environment in which they are built (extra-urban, urban or rural), brings substantial benefits to road traffic. These benefits consist in improving the flow of road traffic by increasing the volume of vehicles passing through such an intersection, increasing the level of safety, decreasing the number and severity of undesirable events (road accidents). This scientific paper represents in an elegant and logical manner a research, but also a personal point of view of the authors on roundabout intersections as a basic element of modern road infrastructure and traffic. In this way, those interested can learn from the context of the work about certain interpretations, definitions, concepts, constructive elements, geometry, design concepts, dimensional values of elements, formulas for calculating capacity and the main elements influencing the capacity of vehicle throughput, classifications, characteristics, advantages, access rules, vehicle traffic rules and the stages of designing roundabout intersections. It also presents a case study of some roundabout intersections that have a special design (turboroundabout, tear-type roundabout and magic-type roundabout). Conclusions drawn on the basis of the research data are presented at the end of the paper.