SIMULATION MODEL FOR INTERSECTION FLOWS FOR MIXED TRAFFIC

Abstract

Traffic simulation modelling has been known as a valuable technique for expeditious assessment of traffic flow characteristics, so that different investment decision with regard to strategies for geometric design and pavement management of roads can be arrived at more rationally. A critical survey of the literature on traffic simulation modelling on a global basis indicates that no suitable model was readily available for the specific traffic and intersection conditions obtained in India and many other similar countries in the developing world. In this study, an attempt has been made to simulate the mixed traffic flow for a 4-legged, right-angled intersection. For the modelling, vehicles, are divided in seven different categories. These are Truck,, Bus, Car, Scooter/Motorcycle, Auto-rickshaw, Cycle-rickshaw and cycle. The scooter and motorcycle are taken in one group. Mixed congruential method is used for generating random numbers and negative exponential distribution has been used for computing headway (the time-headway) between vehicles. A computer simulation model incorporating mixed traffic flow. at intersection is formulated. The computer-program is written in FORTRAN 77 and is run on DEC 2050 which is available at Computer Centre, U.O.R., Roorkee. This program not only generates the type of vehicle, turning movement and their arrival time but also calculates total delay for all the approaches. iv For field data collection, two intersection, both situated on SH 45 were selected and data were collecteu manually. The model is validated by carrying out Chi-square test and by comparing observed and the simulated values w.r.t. percentage error. The applicability of the model is •also discussed. The model can also be used for three leg intersections with minor changes. The study demonstrates that the complex problem of mixed traffic flow at the intersection can be mathematically modelled and analysed by the computer simulation technique. The results of the study may be used for improving the intersection condition.