It is known that the availability of a road network of an appropriate level of service and qualityrnis vital in facilitating the overall economic development of a country. In this regard, Ethiopia, arncountry which is on the fast- track of rapid economic development, obviously requires a roadrnnetwork which is able to cater for the vast traffic/transport demand.rnIn recent years, the quality of many of the major trunk roads in the country has beenrncompromised, as the roads have experienced deterioration, which has given rise to the need forrnperiodic maintenance and rehabilitation. One of the major types of distresses observed on majorrnsections of the trunk roads is permanent deformation in the form of rutting. Performance ofrnroads with regards to ride-ability and roughness is known to have a considerable cost implicationrnto the road users in terms of operational cost, in addition to affecting their safety and comfort .rnPermanent deformation, in this regard has a detrimental effect.rnRutting in paved roads can be attributed to various factors such as the pavement structure,rnquality of individual constituent pavement materials, magnitude and regime of loading,rnenvironmental factors, such as moisture temperature, and others. Despite the fact that HMA mixrndesign has evolved from the conventional empirical mix design approaches (Marshall andrnHveem), to the state-of-the-art and more advanced Superpave procedures, due to the lack ofrntechnological advancement, the customary Marshall mix design and testing method, bearing therneffects of its empiricism, is what is currently being utilized to design ' better' performing HMArnmixtures.rnThis research focuses on assessing the effects of aggregate and mixtures properties on the ruttingrnperformance of HMA wearing (surface) course mixtures, by attempting to establish correlationsrnbetween the independent variables (HMA aggregate and mixture properties) and the dependentrnvariable (rut depth), still adopting the fairly simple and readily available Marshall mix designrnand testing procedure . To meet the objectives of the study, various tests were conducted onrnHMA core samples, obtained from a pertinently rutted trunk road segment, selected for the casernstudy -Gohatsion-Dejen Road Segment. Statistical correlation analysis coupled with subjectivernevaluation was then adopted to assess the effects of the various aggregate and volumetricrnparameters on the rutting performance of HMA mixtures.rnThe results of the study revealed that mixes with higher air void content (in-place and recompacted),rnlower voids filled with asphalt( in-place and re-compacted), lower Marshall flowrnvalue and higher coarse aggregate angularity generally perform better with regards to rutting. Itrnwas also found that 0.45 Power Gradation plots give an important indication on the effect ofrnaggregate gradations on the rutting performance of mixtures, and that mixes with aggregaterngradations, which plot on the coarser side of the maximum density line, generally perform betterrnwith regards to rutting. On the other hand, the inadequacy of the mere 75 blow MarshallrnEffects of Aggregate and Mixture Properties on the Rutting Performance ofrnHMA Wearing course ( A case study on the Gohatsion - Dejen Road Segment) AAUrnBy Abraham Efraem v August, 2014rnCompaction approach to simulate traffic loading in excess of one million ESA's, forrnrepresenting the current levels of high traffic loadings was also underlined. Moreover, it wasrnnoted that the legal load limit of the country, which is 10 tonnes axle loading, is beingrnexceeded, which would prove to have a considerable effect on the rutting performance ofrnmixtures.rnFinally, suggestions were made on how to design HMA mixtures with better rutting resistance,rnstill adopting the customary Marshall mix design procedure, coupled with the refusal densityrnapproach, and the 0.45 Power Gradation Chart.rnKey words: Rutting, HMA, Re-compacted, Stability, Flow, Angularity, Voids, Va, VMA, VFA,rnstripping Marshall Mix Design,