Performance Evaluation of Asphalt Mixes Containing Steel Slag Aggregate as a Measure to Resist Studded Tire Wear

Abstract

Studded tire wear can lead to the severe deterioration of asphalt pavement; therefore, the reduction of studded tire wear is urgently needed to improve asphalt pavement conditions and save repair costs. Steel slag is a coproduct of the steel industry and features high hardness compared to conventional crushed aggregate, such as granite and limestone. This study evaluated the performance of hot-mix asphalt (HMA) that contains steel slag aggregate (SSA) as a surface material to mitigate studded tire wear. The physical properties of the SSA were assessed to determine its suitability in HMA. Four percentages (0, 20, 40, and 60%) of SSA were used in asphalt mixes, and the mix designs for the HMA were conducted in accordance with Superpave mix design. The performance of the mixes was evaluated comprehensively in terms of studded tire wear resistance, thermal cracking resistance, moisture susceptibility, and rutting. The results indicate that the addition of steel slag increased the mixtures’ studded tire wear resistance, dynamic modulus values, thermal cracking resistance, and rutting resistance. The inclusion of SSA had no effect on top-down fatigue cracking resistance and moisture susceptibility. Based on these laboratory test results, SSA could be especially beneficial in the northwest region of the United States in surface courses where studded snow tires are used regularly, and could be used to extend the service life of the pavement.