The Indonesian Highway Capacity Manual (IHCM) project has conducted surveys at 35 road segments in eleven cities using video camcorders synchronised with a 32 channel data logger. The collected data included traffic flow and composition, travel time, existence of queues, and frequency of different types of side friction events. An interim IHCM for urban and semi-urban road links was published in January 1993. The following pcu values for urban roads were obtained: heavy vehicles, 1.2; motor cycles, 0.25 and unmotorised, 0.8. Major influencing variables on speed-flow relationships, which were modelled according to Greenshields, were carriageway width, side friction and city size. Free-flow speeds were 5-15 km/h Free-flow speeds were 5-15 km/h lower than in developed countries, but capacities were slightly higher. (A)
Abstract