Assessment of the mechanical properties of a hot-mix asphalt modified with biochar derived from oil palm kernel shells

Abstract

The increasing generation of agro-industrial waste, such as Oil Palm Kernel Shell (OPKS), poses environmental challenges. This study explores the valorisation of OPKS through pyrolysis to produce Biochar (OPKSB) and its use as a modifier for asphalt cement (AC 60/70). AC was modified with 5-20% OPKSB by weight, and its physical and rheological properties were evaluated. A 10% OPKSB/AC blend was selected to produce a hot mix asphalt (HMA) by the wet process. Performance of the modified HMA (HMA-OPKSB) and the reference mix (Control HMA) was assessed under Marshall, Indirect Tensile Strength, resilient modulus, rutting, fatigue and Cantabro tests. The results show that OPKSB tends to increase the viscosity, stiffness, ageing resistance, rutting resistance and fatigue resistance of AC. It also helped to improve HMA performance (increased strength under monotonic loading, stiffness under cyclic loading, resistance to permanent deformation and fatigue and resistance to moisture damage and ravelling).