Estimation of Motorcycle Equivalent Unit Using Multiple Linear Regression and Impact of Motorcycle on Saturation Flow Rates (A case study of intersections of Kathmandu valley)

Abstract

Kathmandu valley’s traffic is dominated by two-wheeler. The equivalence unit as suggested by Nepal Road Standards, 2070 is same for urban as well as rural roads. Unstable queue formation during peak hours is a common phenomenon of intersections in the valley. Since, Passenger Car Equivalence has been in used in countries where traffic is dominated by cars, the need for Motorcycle Equivalence Unit is obvious for the traffic stream hugely populated with motorized two- wheelers. Relevant information regarding headway and saturation flow can only be obtained from using dominating mode of transportation as a standard vehicle. The study of eight different intersections of Kathmandu valley was conducted with the help of recorded videos of vehicular movement in through and right turning direction. Multiple linear regression technique was used to calibrate motorcycle equivalent units using “R” database software. This study deduces that Nepal Road Standards, 2070’s Passenger Car Unit values of various group of vehicles is not applicable for urban intersections of Kathmandu valley. The average headway for through traffic is 0.47 second and for right turning traffic is 0.56 second. The saturation flow rate for through vehicles is 7,625 motorcycles per hour per lane and right turning vehicles is 6,492 motorcycles per hour per lane. This study also shows that the increase in proportion of two-wheelers in traffic stream decreases headway whereby increasing saturation flow rate.