Unbound Pavement Shoulder Drop-off Measurement for Flexible and Rigid Pavement in Dhaka Roads

Abstract

Pavement edge drop-off plays a major role in road safety. A significant shoulder drop-off may result in a loss of vehicle control. Despite current specifications, the road agencies of Bangladesh do not have a specific edge drop-off criterion. In addition, there is no reliable way to measure shoulder drop-offs. Several roadways have unbound type shoulders, resulting in increased drop-off issues. Rigid pavements, which are fewer in number than flexible pavements in Bangladesh, also show similar issues due to a lack of shoulder compaction. In this study, several sites constructed by different road authorities were evaluated, and shoulder drop-off was measured using an indigenously made profilometer. Upon analysis of the result, it was found that the profilometer is capable of measuring shoulder drop-off accurately and can give a clear idea about the profile of the drop-off. This information can be used to plan effective road maintenance and prevent accidents due to shoulder drop-offs. Regular use of the profilometer can help ensure the safety and integrity of roadways in the long ter