Resumen
The traffic composition on multilane highways in India comprises of a wide range of vehicles in terms of their type, size, engine power, manoeuvring ability, etc. This mix of vehicles with different operating capabilities results in a broad range of speed. Slow moving or non-motorized vehicles occupy the lower ranges of speed spectrum whereas the new technology cars dominate the higher ranges. To understand the real traffic behaviour, it requires quantification of some of the basic traffic flow characteristics such as Speed, Flow, Density and Occupancy through which the capacity can be derived. The radical changes in road network and vehicle technology have resulted in variations in speed-flow characteristics and subsequently road user costs. The problems arise out of three major aspects associated with several types of vehicles in the traffic mix i.e. speed and acceleration capabilities of vehicles, their manoeuvres and lateral clearance requirements within the right of way. The main objective of the present study is to estimate the basic traffic flow parameters for six lane divided traffic stream under study and to evolve speed-flow relationships for six lane divided carriageways for different vehicle types. In the present study, linear models have been developed for speed-flow equations for different vehicles on each lane of selected road sections of six-lane divided carriageway.