Assessment of nanoparticles dispersion in asphalt during bubble escaping and bursting: Nano hydrated lime modified foamed asphalt

摘要

Saving mixing energy by using escaping and bursting bubbles during the production process of nanomaterial-modified water-foamed asphalt is a novel preparation idea, which can be taken as one type of cleaner physical warm-mix asphalt technology. The objective of this study is to assess the dispersal of nano hydrated lime (NHL) particles in the asphalt using a scanning electron microscopy (SEM) test, and to evaluate the physical properties of NHL modified water-foamed asphalt (NMFA). In this study, the NHL and sodium dodecylbenzene sulfonate (C12H25C6H4SO3Na) were added to the water to form suspensions, and the suspensions were mixed with asphalt to form NMFA. The X-ray diffraction (XRD) test was used in order to understand the NMFA's microstructure and dispersal of NHL in water-foamed asphalt. The dynamic shear rheometer (DSR) and the asphalt binder cracking device (ABCD) were also used to evaluate the high temperature and low temperature performance of NMFAs, respectively. The SEM images show that the NHL particles were well dispersed in the water-foamed asphalt while the XRD test results confirmed it and demonstrated that the NMFAs may form an intercalated microstructure. In addition, the presence of NHL reinforcement in the water-foamed asphalt stiffens the asphalt, consequently decreasing the rutting potential. The addition of NHL also increased the low temperature cracking resistance of NMFAs, i.e. decreased the cracking temperature and increased the fracture stress. (C) 2018 Elsevier Ltd. All rights reserved.