Effects of γ radiation on rutting and fatigue performance of WPET asphalt mixtures

Abstract

The generation of large amounts of waste polyethylene terephthalate (WPET) has caused serious environmental and health issues. This research aims to look into the potential reuse of WPET as a secondary material in highway construction and to assess the effect of gamma irradiation on the properties of WPET for use in asphalt concrete (AC) mixtures. Regular and gamma-irradiated WPET granules were used in AC mixes at optimal asphalt content levels. In different quantities, conventional granite aggregate was replaced with WPET granules (0, 10%, 20%, 30%, and 40% by volume). X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry were used to examine the mechanical and thermal properties of regular and gamma-irradiated WPET. Rutting tests were done at 60 ºC, and indirect tensile fatigue testing were performed at 20 ºC. Analytical investigations demonstrated that gamma irradiating WPET increased its mechanical and thermal qualities. Rutting experiments revealed that AC mixes containing WPET granules had lower rut depths than the control mix. The mixes containing standard WPET that had been modified with 20% WPET had the least rut depth. The substitution of granite aggregate in mixes containing gamma-irradiated WPET could be up to 40% while maintaining better rutting resistance. Furthermore, fatigue results revealed that WPET-modified AC mixes had considerably greater fatigue failure cycles at all stress levels than the control mix. Notably, AC combinations containing conventional WPET performed better than those including gamma-irradiated WPET. This study demonstrates how gamma irradiation improves WPET properties in AC mixes.Both regular and gamma-irradiated WPET-modified AC mixes outperformed the control mixture in terms of rutting and fatigue cracking resistance, adding to material sustainability in highway construction.