Experimental analysis of the influence of SBS/nanoclay addition on asphalt fatigue and thermal performance

ABSTRACT

The aim of this study is to investigate the impact of nanoclay and its combination with Styrene-Butadiene-Styrene (SBS) on fatigue behaviour of hot mix asphalt. With respect to four-point beam fatigue and Indirect Resilient Modulus at low and mid-temperatures, pairwise comparison was done over both aged and unaged modified specimens, including 6% nanoclay, 6% SBS, 2% nanoclay +4% SBS and 4% nanoclay +2% SBS. In addition, indirect tensile strength was performed at mid-temperature of 25 °C. The results indicated that nanoclay enhanced fatigue and thermal cracking resistance of unaged and aged mixes. It was found that, at low temperatures, SBS and nanoclay have negative effect on fatigue life and thermal cracking. Moreover, nanoclay was proved to improve fatigue performance of the SBS modified mixes at mid-temperature.

KEYWORDS:

• Polymer modified asphalt
• nanoclay
• fatigue behaviour
• tensile strength
• resilient modulus