A computer program to model capacities, queues and delays at roundabouts is described. It incorporates the latest roundabout entry capacity formula and time-dependent queueing equations. The basic inputs are certain geometric characteristics of the roundabout, the turning proportions of the traffic, the percentage of heavy vehicles in the traffic and a time 'profile' of demand flows (or less detailed demand flow information from which the program synthesises a profile). the program calculates, for each of a succession of time intervals, the capacity, queue length and delay for each entry and enables the growth and decay of queues to be monitored and the calculation of overall delay. A full example is included. (Author/publisher)
Abstract