Static Tensile Behavior and Marshall Stability of Asphalt Concrete Made With Modified Buton Asphalt

Modified Buton Asphalt (MBA) is a refined binder produced by combining petroleum bitumen with natural rock bitumen, abundantly available on Buton Island, Indonesia. This study investigates the tensile behavior and stability performance of asphalt mixtures containing MBA under short-term immersion in water and Na₂SO₄ solution for ۱, ۳, and ۷ days. Core samples extracted from field pavements were subjected to Indirect Tensile (IDT) tests to evaluate moisture susceptibility and tensile integrity. Key mechanical parameters—tensile strength (σt), tensile stiffness modulus (ET), and tensile index (TI)—were derived from the stress–strain relationships, while Marshall stability and flow were assessed to examine the structural integrity of the mixture. The results indicate that immersion duration significantly affects the bituminous matrix but not the coarse aggregate framework. After ۷ days of immersion in water, the tensile strength decreased by approximately ۱۱.۶%, while immersion in Na₂SO₄ resulted in a ۱۵.۲% reduction compared to unconditioned specimens. Correspondingly, the tensile stiffness modulus dropped by about ۹.۴%, indicating minor degradation of the MBA-filler interface. Despite these reductions, Marshall stability remained above ۹۵% of the control values, confirming the structural durability of MBA-based asphalt. Overall, MBA mixtures exhibit good resistance to moisture and salt-induced weakening, highlighting their suitability for tropical pavement applications.

کلیدواژه ها:

Modified Buton asphalt ، Static Tensile Behavior ، Marshall Stability ، Asphalt concrete ، product innovation