Use of Pulverized Fly Ash in Asphalt Concrete Mixture

The increasing wastes and by-products from the rapidly developed industries
nowadays, has become a major concern globally, whereby, on howto handle these wastes
and by-products properly without causing any damages to the society and environment.
Among the wastes/by-products from the industries are such as, steel slag ash, kiln dust,
blast furnace slag and much more. In this study, the concern will be on Pulverized Fly
Ash (PFA), which is a by-product from the coal combustion industry. The highway
construction requires lots of raw material from the natural resources. Hence, researches
on incorporating industries wastes into asphalt pavement, to reduce consumption and
need on virgin aggregates are indeed important. In this study, experiments will be
conducted to studyon the characteristics of asphalt concrete mixture when PFAis mixed
into the mixture rather than using OPC as filler. MarshallMix Test will be carried out to
determine the optimum binder content (OBC) for both mixtures in order to design or
determine the material proportions to prepare samples for performance tests, hi this
study, the samples are prepared by using 55% of coarse aggregates, 40% fine aggregates
and 5% filler (both for OPC and PFA mixtures) and the OBC for both OPC and PFA
mixtures are 5.58% and 5.45% respectively. Among the performance tests involved in
this study are Wheel Tracking Test (deformation/rutting) andBeamFatigue Test (asphalt
concrete mixture deterioration). The obtained results will be analyzed and discussed to
determine the advantages or disadvantages of incorporating PFA into asphalt concrete
mixture in engineering aspects, such as workability, permanent deformation, fatigue life
and flexural stifmess. From the performance tests conducted, PFA mixture has lower
permanent deformation, higher flexural stiffness but lower fatigue life as compared to
conventional mixture.