Measurements of saturation flow were made at nine signal-controlled intersections where there was a considerable flow of two-wheeled vehicles. By relating the flow of light and heavy vehicles in each cycle to the corresponding flows of motorcycles and pedal cycles, it was possible to estimate the effect of a motorcycle and a pedal cycle on the saturation flow, and to express the results in terms of passenger car unit (p.c.u.) equivalents. This was done sparately for each site, and also separately for the first 0.1. minute of the green period and the remainder of the saturated period. The p.c.u. values varied significantly from site to site. but this variation did not appear to be related to the width of the approach . The p.c.u. values tended to be rather lower for the 0.1 minute than for the remainder of the saturated period, but not sufficiently so to justify the use of different values in practical calculations. The average p.c.u. values for the remainder of the saturated periods were. 1 motorcycle = 1/3 p.c.u. / 1 pedalcycle = 1/5 p.c.u.
Abstract