Samenvatting
The existing method for calculating capacity, known as the unified formula, is considered to be unsatisfactory for large roundabouts because it shows capacity increasing with roundabout diameter whereas for diameters greater than around 100 m the reverse is believed to be the case. A simple procedure is suggested whereby the input used in the unified formula can be adjusted to calculate the capacity of large roundabouts. The predicted shortfall in capacity will depend upon the diameter and the various entry and circulating flows.