Abstract:
This study has been conducted in Agaro-Dedesa Road segment which is located in
western Oromiya regional state to identify causes of pavement early failure and to
recommend remedial measures.
The existing engineering properties of the pavement materials, have been the causes of
road failure and the extent of defects were evaluated based on this possible measures to
meet its design life without further pavement deterioration have been recommended.
In order to determine in-situ conditions of road material previous study in the area and
document from the client has been collected. In addition to this, necessary laboratory
tests were carried out on representative samples extracted from the site. The data
obtained from the field investigation and laboratory tests were analyzed and interpreted
by explanatory and comparative analytical methods. Normal test procedures have been
used to investigate the property of the soil, even though there may be a possibility that the
soil in the study area can be lateritic soil type
The results of the study showed that the causes of early deterioration of the pavement are
weakness of subgrade material, pavement material quality, thickness of base and sub
base course. In addition to these, premature failure has been induced due to poor
compaction of pavement layers during construction. Based on this, it recommended that
the subgrade soils shall be replaced or stabilized chemically/mechanically to meet the
pavement design life
