Suitability of Saw Dust Ash and Quarry Dust as Mineral fillers in Asphalt Concrete

Abstract

This study attempts to justify how suitable a conventional mineral filler and a non-conventional mineral filler can replace fractions of the aggregates in an asphalt concrete in order to reduce cost and encourage reuse of waste materials. Asphalt concrete mix proportions were generated with 3% Quarry Dust and 3% Saw Dust Ash replacements of aggregates. The binder contents were 3, 4, 5, 6 and 7% for a 60/70 penetration grade asphalt binder. Briquette specimens were formed using the asphalt concrete mix proportions carried out. Standard laboratory experiments were carried out on the aggregates, Quarry Dust, Saw Dust Ash, bituminous binder and asphalt concrete specimens based on the relevant codes and standards. The Marshall method was used for the asphalt concrete design procedure. The optimum binder content was found to be 4.85% using the standard Marshall curves. At optimum binder content, using 4% design air void for medium traffic and maximum aggregate of 10mm, the Stability, Flow, VMA and VFA were 5.83kN, 15.73(0.25mm), 15.28% and 73.25% respectively. These were within the Asphalt Institute design criteria.