Abstract:
Filler, as one of the components in asphalt mixtures, plays an effective role in their properties and
behavior, especially regarding binding and aggregate interlocking effects. Mineral fillers and
different aggregate gradation have a great effect on the mechanical property of asphalt concrete
pavements. One of the main problems in the construction of asphalt paving mixture is obtaining a
sufficient amount of qualified filler material. To overcome this problem it is important to come
across alternative filler material that can address this gap which is easily available. The effects of
different minerals are introduced on the performance of hot mix asphalt. However, the influence
of Belessa Kaolin on the performance of HMA mixture with Superpave aggregate gradation are
not properly established. This research is conducted by using laboratory experimental research
design and Non-Probability sampling techniques adopted. In this research, the effect of non conventional material so called Belessa kaolin and superpave gradation on marshal Properties,
moisture susceptibilities and permanent deformation in asphalt mixtures was investigated. The
chemical composition of Belessa kaolin shows that the total content of Silicon Dioxide (SiO2), Iron
Oxide (Fe2O3) and Aluminum Oxide (Al2O3) was 65%, 24.1% and 1.84% respectively. The
physical properties of Belessa kaolin was conducted on specific gravity and Plastic Index were
2.62 and 3.24 respectively. Both the physical and chemical properties were address the
requirements according to ASTM C-618. Based on the study area characteristics bitumen grade
of 60/70 penetration is selected. HMA specimens were prepared from three different Superpave
gradation with conventional filler Crushed Stone Dust (CSD) of different proportion (5.0%, 6.0%,
and 7.0%) and five different bitumen content (4%, 4.5%, 5% 5.5% and 6%). A hot mix asphalt
with 5.0% of CSD were selected as control mix based ERA specifications. The conventional filler
was replaced by Belessa kaolin at different replacement rate (0%, 10%, 20%, 30%, 40% and 50%)
on the basis of control mix with 5% CSD and 5.1% OBC. Marshal properties and moisture
susceptibility were performed to determine the optimum replacement rate of Belessa kaolin. The
replacement rate of 30% of Belessa kaolin provide better marshal properties and resistance to
moisture susceptibility. This study also investigated the rutting resistance characteristics of HMA
with optimum Belessa kaolin and control mix. The results of the experiments indicated that the use
Belessa kaolin on HMA has fulfilled the criteria specified on the specification
