Stability Improvement of Asphalt Concrete Binder Course using LDPE Plastic Waste with Lignin as Coupling Agent

Development of plastic waste as an asphalt mixture inhibited by its compatibility. In this study, the addition of weight variations modified lignin as coupling agent in Asphalt Concrete-Binder Course (AC-BC) with LDPE mixture was investigated. Asphalt, Polymer Modified Bitumen with and without lignin addition were characterized by physical analysis using Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. While the AC-BC pavement was analyzed by mechanical analysis using marshall parameter. The addition of plastic to asphalt will form agglomeration and after lignin was added the agglomeration reduced. The reduced formation of plastic agglomeration due to lignin addition in asphalt form Van der Waals reaction was indicated by peaks alteration from 1041.77 cm −1 to 1031.11 cm −1 at the maximum addition of lignin. Moreover, the marshall stability of the AC-BC pavement was enhanced up to 89.5% at optimum lignin addition. Lignin utilization as a coupling agent of asphalt and LDPE can be a solution to the weaknesses of asphalt plastic technology while solving the plastic waste problem.