ABSTRACT
In this paper, review of Croatian national guidelines is given, with the emphasis on the geometric design and fastest path (speed profile) analysis. The review is presented through several theoretical examples of single-lane suburban roundabouts with various external radii, designed according to the recommendations of these guidelines. Design vehicles used in this analysis are truck with trailer, semitrailer truck and tri-axle bus. These vehicles occupy different swept path widths when moving through the roundabout with the same external radii, which leads to differences in resulting entrance and exit widths and consequently the speed profiles on roundabouts. These differences, as well as the impact of analyzed design vehicles on the roundabout geometric design and speed profile, are also presented.
