Study on mode I, mode II and mixed mode I/II fracture behavior of hot mix asphalt containing silane crosslinkable polyethylene waste. (April 2023)

• Record Type: Journal Article
• Authors: Pourfeiz, Alireza; Modarres, Amir; Ghodrati, Ali; Ayar, Pooyan; Yousefi, Afshar A.
• Is Part Of: Theoretical and applied fracture mechanics. Volume 124(2023)
• Publication Date: 2023-04
• Subjects: Hot Mix Asphalt (HMA) -- Silane-crosslinked polyethylene (Si-XLPE) -- Fracture toughness -- Fracture energy -- Flexibility index -- FESEM; Fracture mechanics -- Periodicals; 620.1126
• DOI: 10.1016/j.tafmec.2023.103810
• Languages: English
• ISSNs: 0167-8442

Abstract

Highlights: Study investigated the fracture behavior of HMA containing Si-XLPE. Investigation was under pure mode I, pure mode II, and mixed mode I/II. Incorporating Si-XLPE into bitumen altered the fracture behavior at low-temperature (-20 °C). FESEM analysis exhibited a uniform dispersion of 1.5% Si-XLPE in the bitumen matrix. Abstract: Polymeric bitumen modification is widely employed to improve the performance of asphalt mixtures against some distresses such as fatigue damage, rutting and stripping. Silane-crosslinked polyethylene (Si-XLPE) waste, with better thermal, elasticity and mechanical properties than conventional polyethylene, is usually incinerated or landfilled due to some challenges in recycling such crosslinked wastes. This study investigated the fracture behavior of hot mix asphalt (HMA) containing 0 %, 0.5 %, 1 % and 1.5 % Si-XLPE under pure mode I, pure mode II, and mixed mode I/II at 25 °C, 0 °C and −20 °C through semi-circular bending (SCB) test. Results indicated that with increasing Si-XLPE content up to 1.5 %, fracture toughness of the modified HMA in the mixed mode I/II of loading, which was mainly the most critical loading mode, increased by 26.5 % and 16.9 % at 0 °C and −20 °C SCB testing, respectively. Incorporating Si-XLPE into the base bitumen altered the fracture behavior of HMA at low-temperature testing (-20 °C) from brittle-ductile to ductile, leading to an unpredictable reduction of fracture energy with a temperature decrease from 0 °C to −20 °C. FESEM analysis exhibited a uniform dispersion of 1.5 % Si-XLPE in the bitumen matrix, which was not achieved by adding 0.5 % and 1 % Si-XLPE.