Study on low cost safety improvements of selected arterial roads in metropolitan Dhaka city

Abstract

This thesis presents the findings of a study concerned with low cost safety improvements of the selected arterial roads under Demra Metropolitan Police Station in Metropolitan Dhaka. The selected road locations included sections of Dhaka-Chittagong highway and Dhaka- Narayanganj road and are composed of five intersections and eleven links. It examines the trends and characteristics of the accident problems for identitying the dominant accident types which need to be tackled in future initiatives. A total of 517 accidents occurred on these roadway sections over the three & a half years period, January 1992 to June 1995. Of the total 517 reported accidents, 22.5% took place at intersections and the remaining 77.5% at links of road (mid-blocks). These accidents were distributed as 33.8% fatal, 48.6 % injury and the 17.6% property damage only accidents. The Pedestrian accident problem emerged as the most serious problem . Rear end and overtaking accidents were also featured as the dominant problems. In the study area accidents peaked between 8 am and 2 p.m. Most of the major accidents occurred due to reckless and appropriate driving of the truck and bus drivers. Trucks were mostly involved in accidents ( 27.3% ). These were followed by buses (22.0%) and minibuses (11.8%). The maximum operating speeds of cars, buses and trucks were 85 km per hour, 76 km per hour and 75 km per hour respectively with average vehicular speed of 64 km per hour. Detailed investigation of hazardous intersections and road links (mid-blocks) were made using available accident data, field investigations and taking photographs of most hazardous sites. Collision diagrams were drawn for the most hazardous intersections and links to determine the types of accidents and vehicles involved in the locations which gave clues as to the remedies required. Narrow roads, increasing road traffic, lack of pedestrian facilities and lack of road use sense among the road users were considered to be the main causes of road accidents on these roadway sections. Some of the low cost traffic engineering countermeasures have been recommended which can be implemented to help reduce road accidents. Similar countermeasures may be given increased priority in any future initiatives for the safety improvements of other arterial roads.