Laboratory Evaluation of Sulfur Waste Asphalt Mixtures Containing SBS and Waste Polypropylene Polymers

This study analyzes the possibility of using sulfur waste (SW), styrene-butadiene-styrene (SBS) and waste polypropylene (WPP) as sustainable materials in asphalt paving mixtures. Sulfur waste asphalt concrete (SWAC) combinations with virgin (V), SBS and WPP-asphalt binders were constructed for the study. The SW concentration in the asphalt concrete (AC) mixture was set at 5 percent (by weight of aggregate), while the weight of SBS and WPP polymers was set at 5 percent (by weight of asphalt). The tests performed to evaluate the performance and durability were the Marshall stability, Marshall quotient, indirect tension, tensile strength ratio, semi-circular bend and deformation strength in Kim tests. Based on these testing results, all V, SBS and WPP-SWAC combinations meet the minimal ASTM standards of 8kN stability, 2-4 mm flow, 3-5 percent air voids, and 14 percent VMA at the same optimal binder content, SBS and WPP increased the performance and durability of SWAC mixtures. SBS-SWAC mixture showed better performance and durability than the WPP-SWAC mix (i.e. lowering of deformation phenomenon, crack propagation, and moisture damage). In this study, it was determined that SW and WPP can be recycled and used as sustainable materials for paving applications where they available and the cost of transportation is lower than virgin materials.