Evaluation of Asphalt Blended With Low Percentage of Carbon Micro-Fiber and Nanoclay

Abstract

Abstract The objectives of this study are to investigate the applicability of carbon micro-fiber and nanoclay in asphalt binders and to evaluate the performance of micro- and nano-modified asphalt (NMA) binders in terms of rheological properties. Due to their unique characteristics, micro- and nanomaterials were hypothesized to play a critical role in enhancing the performance behavior of asphalt binders. In light of existing research, carbon micro-fiber (MCF) and Nanomer I.44P (NI.44P) were selected as the micro- and nanomaterials for this research. Then, these materials were added into the PG 58-34 control asphalt binder at the concentrations of 2 % and 4 % by weight. Superpave™ binder tests—rotational viscosity (RV), dynamic shear rheometer (DSR), and bending beam rheometer (BBR)—were then conducted for evaluating the performance of each modified asphalt binder. Also, the characterization tests were run on the aged samples prepared using the rolling thin film oven (RTFO) and pressure aging vessel (PAV) to simulate the short-term and long-term aging. Subsequently, the viscosity, dynamic shear modulus (|G*|) and phase angle (δ) of asphalt binders were analyzed, and the dissipated energy per load cycle was introduced to estimate the asphalt binders’ rutting and fatigue cracking resistance. It was found that the dynamic shear modulus of asphalt binders can be improved by the selected micro- and nanomaterials. Furthermore, the NI.44P modified asphalt showed better properties relative to the other modified asphalt binders or the control (PG 58-34) binder.