Evaluation of Mobility of Multi-Modal At-Grade Intersection using Micro-Simulation (VISSIM)

Abstract

Travel efficiency and road traffic safety of a non-signalized intersection are considered as the two core objectives in the management and control of traffic. Using traffic simulation software is an effective way of solving the problem to pursue a suitable mechanism addressing these objectives. The effect of merging the service road traffic into the main highway traffic before making the U-turn needs to be studied.it was assumed that the mobility of the main highway traffic could be improved by making the service road traffic merged into the main highway traffic before making the U-turn, as opposed to the existing field conditions i.e. the service road vehicles trying to utilize the U-turn and acting as a barrier to the main highway traffic (perpendicular direction of movement to the main highway traffic). Manual count method was used for traffic volume survey during peak hours. Field survey was conducted for distance, time, average speed of vehicles and vehicular dimensions. Geometric condition survey was conducted and road width was measured at different positions. By using VISSIM micro-simulation software we created a model and calibrated according to the field conditions. The mobility of main highway traffic of subject intersection was compared with the proposed model in terms of travel time. Evaluation of traffic flow was carried out by comparing travel times for peak hours with the proposed solution. The results showed that the proposed model reduced the travel time by average of about 25% on main highway. Hence, the simulation results supported the hypothesis of improved traffic conditions after merging the service road traffic into the main highway traffic.