Multilane highways is defined as a highway with at least two lanes for the exclusive use of traffic in each direction, with no control or partial control of access, but that may have periodic interruptions to flow at signalized intersections no closer than 3.0 km. Multilane highways consist of two type which is divided and undivided multilane highways. Divided multilane highways usually have barrier or concrete divider to separate the direction of vehicle travel along the road segment. For Undivided multilane highways do not have divider but has the strip line in the centred of the lane to separate the direction of vehicle. Generally, free-flow speed is affected by the geometric conditions of the road such as lane width, shoulder width, median clearance and access point density. Data collections were conducted at 16 sites (64 lanes) of four-lane highways with level terrain in various states in Peninsular Malaysia.
multilane highways, free-flow speed, geometric conditions