The objective of this consultancy was to analyse and understand the causes of surface dressing failures in Ethiopia, and provide recommendations for improved practice. To achieve this the authors undertook: a review of existing design methods and standard specifications; visited a sample of sites where surface dressings were being constructed and where surface dressing failures have occurred; conducted interviews with government, university and industry representatives; and presented the preliminary study findings to a workshop attended by government and industry representatives. Tender prices in Ethiopia proved to be a sensitive issue, however all other countries in the world that use surface dressings find them to be a cheaper alternative to asphaltic concrete. If surface dressings can be purchased for a lower cost than AC and constructed such that they last the usual lifetime, then the extent of the road network covered each year could be increased, for the same budget outlay.
Neaylon, K.; van Zyl, G. Review of surface dressing practice in Ethiopia: Final Report. (2009) 72 pp.