THE EFFECT OF DISSOLVED PLASTIC POLYMER MODIFICATION ON RUTTING AND FATIGUE RESISTANCE PROPERTIES OF WARM BITUMEN BLEND
Abstract
Recently, large amounts of waste polymers are being generated in Nigeria. One of the waste polymers is plastic bottles. Hot Mix Asphalt (HMA) are produced at high temperatures with high energy consumption and environmental hazard. The purpose of using Warm Mix Asphalt (WMA) is to reduce the production and laying temperature and emission of greenhouse gases. Therefore, this research investigated the effect of Dissolved Plastic Bottle (DPB) on the rheological, rutting and fatigue resistance properties of warm bitumen blend thereby reducing the environmental hazard associated with the Waste Plastic Bottles (WPB) disposal and consequently improving pavement service life. WPB was obtained from different waste generation points in Adeleke University, Ede, Nigeria. The obtained WPB was shredded and converted to dissolved form using pyrolysis machine @ 4500C. 500g of 60/70 penetration grade bitumen was heated in an oven with 3% (15g) sasobit until it becomes fluidal. The bitumen was modified with 0 - 17% by weight of the bitumen at 2% interval. Mixing was continued for 1hour to produce homogenous bituminous mixtures. Rheological tests were then conducted on the prepared samples using the Brookfield programmable rheometer. The results indicated that addition of DPB improves the rheological properties of absolute viscosity, phase angle, complex shear modulus, rutting and fatigue resistance of modified binder at both 135°C and 165°C. Therefore, DPB can be used to improve bitumen rheological properties and subsequently resist rutting and fatigue on traffic roads. This can best be achieved upon 7% and 5% modification levels at 135°C and 165°C respectively.