Chemical, morphological, and high temperature rheological behaviour of Bioasbuton® as an alternative binder for asphalt concrete in Indonesia

Abstract

Asbuton is a natural asphalt from mountains/rocks on Buton Island, Indonesia, with deposits of 677.247 million tons with an estimated bitumen content ranging from 15% to 35% or equivalent to 170 million tons of asphalt. The use of granular asbuton in an asphalt mixture requires modifier/rejuvenating material with low viscosity so that it can enter the asbuton granules more easily and can soften the asbuton bitumen and mobilize it evenly in the asphalt mixture. Coconut shell biobinder (BioCS) is a bio-oil fraction produced from fast pyrolysis of coconut shell, with the ability as a modifier/rejuvenator. The use of BioCS for granular asbuton on asphalt mixtures can be an alternative environmentally friendly road pavement technology. Before conducting tests on the asphalt mixture, it is necessary to test the characteristics of the asphalt binder, which is bioasbuton®, which is a binder from BioCS with asbuton bitumen at an optimum composition that can be used as an alternative binder for asphalt mixture. The tests include a chemical structure test using fourier-transform infrared spectroscopy (FTIR), a morphological and elemental content test with scanning electron microscope (SEM) and energy dispersive x-ray (EDX) analysis, a basic physical properties test with a basic rheological test, and a mechanistic physical properties test through dynamic shear rheometer (DSR) temperature sweep. As an asphalt binder base, the asphalt pen 60/70 was used which was then compared with bioasbuton® and asbuton bitumen. The test results show that the characteristics of bioasbuton® are better than asbuton bitumen and meet the specifications of pen 60/70. Based on the results of this study, prove that bioasbuton® as an alternative asphalt binder that has good potential, especially at high temperature performance.