OPTIMIZATION OF OPTIMUM BITUMEN CONTENT AND MARSHALL CHARACTERISTICS OF AC-WC MIXTURES WITH RESIN GUM ADDITIVE

Abstract

Asphalt pavements in Indonesia are often found to suffer from damage such as cracks, plastic deformation (bumpy roads), and potholes on the surface. These damages are caused by errors in the road implementation, namely the determination of the type of bitumen used, the voids in the mixture, or the compaction temperature. The performance demands of asphalt pavements in serving the intensity of traffic loads and climate variability in Indonesia necessitates innovative approaches in modifying asphalt mixtures. Mastic gum is a viscoelastic natural resin that has the potential to be an alternative solution to improve the stability and mechanical properties of asphalt pavements, where its physical characteristics are very similar to asphalt, namely high viscosity and strong interparticle adhesivity. This research focuses on testing the marshall characteristics and optimising the optimum asphalt content of AC-WC mixtures using resin gum additives using the marshall testing method. The percentage variations of resin gum used were 0%, 5%, 7.5%, and 10%. Parameters tested included stability, density, flow, MQ, VMA, VIM, VFB, IRS, VIM_PRD, and KAO. The results of the marshall tests conducted showed that almost all parameters met the requirements of Bina Marga 2024 technical specifications, although there were still some of them that experienced an increase and decrease at certain mixture levels. Based on the analysis, the optimum resin substitution rate recommended for field application is 5%, which is by replacing 5.42% resin by weight of the asphalt used. This research contributes to the development of alternative materials in asphalt concrete mixtures with good performance results.

Keywords: Marshall testing, marshall characteristics, optimum bitumen content, AC-WC, and resin gum