Development of Speed Prediction Models for Different Categories of Roads

Abstract

Speed is one of the fundamental measures of traffic flow and level of service. It indicates the mobility of vehicle performance and quality of vehicles plying on roads. In the present scenario, due to increasing the more number of vehicles, the average stream speed of the traffic is becoming a bigger concern to traffic planners and engineers. For controlling traffic, optimizing vehicular operations and decreasing the conflicts and predicting the speeds of the vehicles under variable conditions help in better planning of the road network. In this paper, speed prediction equations were developed for different categories of roads network like National Highway (NH-44) at Kompally, State Highway (SH-6) at Gandimaisamma, arterial road at Himayath Nagar and sub-arterial road of Pragati Nagar, Hyderabad. Data was collected during peak hour with the help of the video camera. Vehicular volume and speeds were extracted for an interval of every 10 min. The vehicle speed varies with road geometry depends on different categories of roads. The percentile speed will also vary with functional characteristics of roads. The percentile speeds were calculated for all types of roads, i.e. 15th, 50th, 85th and 98th percentiles. The vehicle volumes are converted into passenger car unit (PCU) for each location. The vehicles classified into two-wheeler, three-wheeler; car, bus and light commercial vehicles. Graphs were drawn for each location by using Greenshield’s model to obtain maximum speed capacity of roads. Regression technique is used to develop an equation for predicting speeds at each location.