Safety aspect of roadway design elements in metropolitan Dhaka

Abstract

'Safety first' is given top most priority in any kind of activity within the transportation planning process. The faults in existing roadway design elements result in innumerable direct economic costs accounting from damage to vehicles. property and medical services for the injured, together with productive potential losses from the injured and death or human lives. According , to World Health Org'anization (WHO. 1989). road accidents claim some 600,000 lives and over 15 million persons are injured every single year throughout the world. This represents more than one life lost every minute and an injury everv 2 seconds. Two thirds of the victims come from the Third World. A TRL Study (1991 ) estimated the minimum annual cost to be I '7c or these countries Gross "'ational product (GNP) resources which they can ill afforr! to lose. On this basis. the total annual cost I'or third world countries is at least 25 billion US dollars. In terms or road safety. Bangladesh stands 7 in ranking with deaths/l 0.000 vehicles below 55 and the personal risk of dying in a road accident. it stands 27 in ranking with death/lOO.OOO people below 2 (Nlost rates 1989 or 1990 sources IRF. IRT AD. country papers). In this project work, a comprehensive analysis has been shown on the safety aspects or roadway design elements in Metropolitan Dhaka. The main attention has been drawn on the two aspects of roadway design elements for safety viz. facilities for pedestrian safety such as footpaths, zebra crossing. foot-over bridge. underpass. safety fences & barriers etc. and vehicular movement safety such as road humps. road markings. medians. traffic signs. channelization and traffic islands etc. An extensive literature review has been conducted to understand different low-cost engineering practices to identify various roadway design elements and understand there potential in improving safety around the world. Field observations at different important locations of the Metropolis have been made to identify and analyze the safety threatening aspects of the existing road design elements. A number of still photographs have been taken to show how these elements are ,generating , safety threats to pedestrians as well as vehicular movement. It has been found that safety fences and barriers are not properly repaired and no painted markings are applied for visibilty at night, sub-standard median width with no pedestrian refuge facility from mid blocks, barriers with exposed sharp end, footpaths are occupied by hawkers and petty dealers, street trading are reducing roadwidth, zebra crossings are faded, road markings are eroded, traffic signs are not mostly cared for by road users. pedestrians are crossing at grade instead of foot over bridge,narrow underpass , road humps are not marked, raised manhole covers on the road surface are giving threats toward safer vehicular movement. A number of safety threatening elements have been identified within the Metropolitan area and recommendations have been made accordingly for remedial measures. The findings of this study would help the policy makers and the safety engineers and planners to formulate for future strategies in improving the existing roadway design elements.