ABSTRACT
The quest for economy in asphalt production using locally available materials necessitated this research which is aimed at evaluating the suitability of Saw Dust Ash (SDA) as mineral filler in asphalt mixture.Chemical analysis, sieve analysis, specific gravity and plasticity index tests were performed on SDA. Asphalt briquettes prepared using Ordinary Portland Cement (OPC) without saw dust as filler serve as the control. SDA was used to replace the Portland cement at 0% to 100% at an interval of 10% by weight. Marshall Test was conducted on all briquettes produced with SDA and OPC. Results of tests show that increase in SDA resulted in reduction in the value of bulk density. It was also observed that the total voids in the mix increased with SDA content, while the values of stability and flow decreased with SDA. The optimum bitumen content of 6.0% was used to prepare specimens. The flow value of asphalt decreased from 2.0mm when only the cement was used as filler to 1.0mm when the cement was completely replaced with 100% SDA. Voids in mineral aggregate increased from 18.28% when 100 % cement was used as filler to 26.32% when cement was completely replaced with SDA. Based on results of tests, the use of cement partially replaced with 10% SDA at 6% bitumen content is recommended for use in asphalt production.