Investigating the indirect tensile stiffness, toughness and fatigue life of hot mix asphalt containing copper slag powder

ABSTRACT

This paper presents the results of an experimental investigation accomplished on hot mix asphalt (HMA) containing copper slag powder (CSP) as filler material compared to conventional HMA prepared with limestone powder (LSP). Indirect tensile strength (ITS), resilient modulus (M _r) and fatigue tests were performed on four groups of HMAs containing 6% LSP, 4% LSP + 2% CSP, 2% LSP + 4% CSP and 6% CSP by total weight of aggregates. Furthermore, the environmental impacts of using CSP were investigated using toxicity characteristics leaching procedure test. Based on the obtained results, the mechanical properties of HMA improved by increasing the CSP content. On average, the ITS, TI_it, M _r and fatigue life of HMA containing 6% CSP were 10.2, 8.5, 7.5 and 21.6% higher than the control mix. The results of correlation analysis showed a significant relationship between the fatigue life-M _r and fatigue life-TI_it parameters. For all strain levels, the correlation coefficients obtained for TI_it were higher than those obtained for M _r. Concentration of heavy metals in leachates gathered from the CSP and the HMA containing this filler satisfied the needed criteria.

KEYWORDS:

• Copper slag powder
• toughness index
• fatigue life
• resilient modulus
• leachate properties