الفهرس 
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Abstract
Among the nanomaterials, nanosilica (NS) is widely used in asphalt
modification research. However, the high price and limited available quantities
of NS interdicts its practical use in pavement construction. This study attempts
to find viable alternatives that offer a comparable performance of NS. Raw
nanoclay (NC) and nano-silica fume (NSF) are the suggested alternatives for
this purpose. Therefore, NSF as an industrial waste material was employed at
low contents (2, 4, 6, and 8%) and high contents (20, 30, 40, and 50%) by
asphalt weight as modifying additives to the asphalt binder. Besides, NC was
used at the content of 2, 4, 6, and 8% by asphalt weight. While NS was
employed at the content of 2, 4, and 6% by asphalt weight for the comparison
purpose.
The asphalt samples were mixed with nanomaterials using a high-shear mixer
at various speeds and durations to select the appropriate mixing conditions to
achieve a homogeneous blending. Transmission Electron Microscopy (TEM)
was used for scanning the nanostructure particles and Scanning Electron
Microscopy (SEM) was performed to assess the homogeneity of modified
binders. Changes in the chemical bands of the modified asphalts were
investigated using Fourier Transform Infrared Spectroscopy (FTIR). The
physical- rheological properties, temperature susceptibility, aging effect, and
economic benefit of the modified binders were also investigated. In addition,
prediction models were utilized to predict the rutting parameter (G*/sinδ) ِِof ِِ
the modified asphalt. Moreover, the effect of modified asphalt on the
concentrations of environmental and healthy harmful metals in the leachate
water was investigated. The stiffness, moisture damage, rutting, and fatigue of
the hot asphalt mixtures prepared with modified binders were evaluated using
Marshall, indirect tensile strength, and double punching tests. Moreover, the
Mechanistic-Empirical Pavement Design software (AASHTOWare Pavement
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ME Design) was used to predict the field pavement performance of both the
control and modified asphalt mixtures