Each scenario describes a fixed roundabout phenomenon using the following variables: geometric elements (inscribed circle radius, circulatory roadway, central and splitter islands etc.); characteristics of the traffic flow (dynamic traffic assignment, approach speed, circulatory speed and reduced speed ...
Figure6(b)illustrates the impacts of signal cycle length and central island diameters on the capacity of a left-turn lane. Similar to the through lane, the capacity of a left-turn lane increases with the central island radius getting larger. However, the cycle length has a relatively complicat...
of vehicles in the roundabout depends on its radius and the distances between the vehicles, (ii) the velocities of the vehicles determine the time in which they cross the intersection and, (iii) the safety time, which influences the safety distance, determines the minimum distance between ...
Sustainability 2015, 7 5842 V can be calculated through the procedure shown in the NCHRP Report 672, "Roundabouts: An Informational Guide" [19], as a function of the deflection radius of the vehicle trajectories. For T = 5.5 s from Equations (3) and (4), we can obtain the stop-...