GIS TOOL TO OPTIMIZE ROUTE PLANNING TO IMPROVE ENERGY EFFICIENCY OF MOTOR VEHICLES IN SRI LANKA

Abstract

Transportation has become a vital part of economic development of a country. Poor transportation planning and management is not only waste valuable time but also wastes lot of energy and creates unnecessary air pollution. In recent years, Sri Lanka also has experienced a high growth rate in urban population and the number of private vehicles. Most evident feature of such a trend is urban road congestion. Most of the main roads and local roads in some urban areas are facing unexpectedly high traffic flows which cause time waste in transit, environmental pollution and huge losses to the economy of the country. Therefore, efficient route planning has become one of an important study area because governments also have identified that build new roads is not the only solution for the traffic congestion problem.

One of the main reasons for traffic congestion is that concentration of vehicles to selected few roads, may be due to shorter length or may be due to their condition. In optimum route planning, it is essential that to identify alternative routes available to connect different origins and destinations that can be used to divert the traffic from congested road links. However, the number of vehicles that can be diverted will depend on the condition of the road links, existing traffic level and also the land use pattern along the routes. This implies that if the routes are planned well and assign traffic accordingly it will help to minimize the congestion on a road network.

The objective of this paper is to present a GIS based model which is called “Integrated Highway Management System” (IHMS) that has been developed by customizing the ArcGIS software using Visual Basic (VB 6) to handle national road network in Sri Lanka. The model is capable of determining the minimum distance or minimum time/cost path between any two node pairs and determining alternate paths avoiding any or all nodes or links between any selected node pair. The model is capable of estimating the traffic flows on road links if the travel demand between the node pair is known. Model is capable of approximately estimating the emission level on road links in addition to the travel time. Moreover, the model has the features of changing the level of operation of a road by using  different adjustment factors by considering the road conditions and land use pattern. This facilitate the designers to plan the road network in an efficient manner that will help to minimize the traffic congestion by identifying the routes which should improved or vehicles should or should not be diverted.