Impact Curing Time and Compaction Methods to the Performance of Hot Mix Asphalt Asbuton

Abstract

Asbuton is rock asphalt located on Buton Island, Indonesia. The contained asphalt is hard and produces very high viscosities, making it very difficult to facilitate uniform coating of aggregates and to bind asphalt mixtures. These challenges in the process of incorporating Asbuton in asphalt mixtures make it less popular than the petroleum asphalt. The current Indonesia standards require Hot Mix Asphalt incorporating Asbuton (HMAA) to be cured for a few days before it is compacted (scenario 1). The curing duration is aimed to allow softening of the natural asphalt contained in Asbuton. This study investigated a new method of conditioning HMAA (scenario 2). The results showed that the volumetric and Marshall characteristics of HMAA were influenced by the curing time and compaction methods. The findings suggest that the curing method proposed in scenario 2 can be omitted; as such it can speed up the asphalting process. This study found that HMAA can be spread and compacted without curing, with a provision made for the road to be closed from traffic for a minimum of eight days after the compaction is complete.