Evaluation of Sulfur Waste as Sustainable Mineral Filler in Asphalt Paving Mixtures

• Published in: International journal of pavement research & technology 2024, Vol.17 (1), p.202-215
• Main Authors: Rasheed, Suad Kamiran, Al-Hadidy, A. I.
• Format: Article
• Language: English
• Subjects: Asphalt; Asphalt pavements; Binders (materials); Building Construction and Design; Calcium carbonate; Civil Engineering; Concrete; Emissions; Engineering; Fillers; Flow stability; Mechanical properties; Mixtures; Original Research Paper; Pavement construction; Paving; Structural Materials; Sulfur; Tensile strength
• ISSN: 1996-6814; 1997-1400
• DOI: 10.1007/s42947-022-00229-z

Sulfur waste (SW) materials are piling up in Iraq, posing a costly disposal issue as well as gas emission concerns. An efficient way to reduce the consumption of a common filler (calcium carbonate; CaCO 3 ) and hazardous gas emissions is to use SW as a mineral filler. For sustainable pavement construction, SW could be used as a mineral filler. This study analyzes this possibility. Sulfur waste asphalt concrete (SWAC) combinations with PG76-16 asphalt binder were constructed for the study, and they were tested against the CaCO 3 –asphalt concrete (AC) reference mixture. While the weight of SW in the SWAC mixtures ranged from 4% to 6% (by weight of aggregate), the CaCO 3 concentration in the AC mixture was set at 5% (by weight of aggregate). Tests on the mechanical properties of AC and SWAC mixtures included the Marshall stability and Marshall quotient, as well as the static indirect tensile strength at 25 and 60 °C, and tensile strength ratio. To a lesser extent, the SWAC combinations have lower Marshall stability, tensile strength, and tensile strength ratio than AC mixture. Even at 5% SWAC, the values of tensile strength ratio are still higher than the minimum values of 85%. A greater flow rate indicates greater strain capacity to achieve failure in SWAC mixtures. All SWAC combinations meet the minimal ASTM standards of 8kN stability, 2–4 mm flow, 3–5% air voids, and 14% VMA at the same optimal binder content. In this study, it was determined that 4–5% by weight of aggregate can be recycled and used as a sustainable mineral filler for paving applications, where it is available and the cost of transportation is lower than CaCO 3 filler materials.