Modified Cutback as Tack Coat by Application of Pyro-Oil Obtained from Municipal Plastic Waste: Experimental Approach

Abstract

Increasing crude oil prices and environmental concerns demand an alternative petroleum-based bitumen binder for Indian road construction industry. In this study, viscosity grade (VG)10 bitumen was modified by adding pyro-oil obtained from municipal plastic waste. The calorific value (10,745 kcal/kg) and the Fourier transform infrared spectra of the specimen pyro-oil were identical to those of diesel and bitumen respectively. This study investigated the use of this specimen as a substitute for diesel to prepare modified cutback bitumen, which acts as a tack coat between two layers of bituminous pavement. All empirical results of the modified cutback were within ASTM limits. Furthermore, using a newly developed attachment to the Marshall stability apparatus, the shear strength of the tack coat was tested at various temperatures. At the rate of application of tack coat as 0.20 kg/m2 and with 20% addition of pyro-oil, the optimal shear strength reached was 331.21 kPa. Dynamic shear rheometer testing determined the complex shear modulus (G*) value to be 1.975 kPa. Due to its adequate performance and green synthesis, the modified cutback bitumen can be a potential solution for use in flexible pavement.