الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Despite the importance of using sulfuric asphalt in road construction, it causes some negative
effects on the physical and mechanical properties of asphalt binders and mixtures. Therefore,
there is a need to address this impact and extend the service life of the pavement and preserve
non-renewable bitumen sources for future generations. It is extremely important that sulfur
asphalt suits the different environmental conditions and the increasing traffic volumes. Under
this hypothesis, this study examines the effect of two different recycled plastic waste (RPW)
which are high and low-density polyethylene (RHDPE and RLDPE) on the
rheological/viscoelastic characteristics and aging performance of virgin asphalt and sulfur
extended asphalt (SEA) and their mixtures. Four dosages of the RPW additives representing
2%, 4%, 6%, and 8% by weight of the asphalt binder were investigated. Then determining the
melting point of the RPW through Differential Scanning Calorimetry (DSC). The optimum
blending time was determined based on the results of the Brookfield Rotational Viscosity (RV)
test. Physical properties (penetration and softening point) and Chemical properties (X-ray
Diffraction and Fourier transform infrared spectroscopy) of RPW-asphalt and RPW-SEA
composites were investigated. The morphology of the investigated blends was quantified using
Scanning Electron Microscopy (SEM). The rheological characteristics of the RPW modified
binders (virgin asphalt and SEA) are characterized at original and short-term aging conditions
through the RV and dynamic shear rheometer (DSR) tests. Fatigue performance is also
characterized at the long-term aging condition. Also, high-temperature performance, dynamic
storage stability (DSS), and multiple stress creep and recovery (MSCR) are studied. The DSR
test was conducted at different frequencies reflecting different highway traffic speeds. Different
historical predictive equations that model the rheological properties of asphalt binders in terms
of dynamic shear modulus (G*) and phase angle (δ) are studied. The investigated models are
employed to describe the rheological viscoelastic characteristics of the different investigated
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binders at different aging conditions under the influence of different frequencies and
temperatures based on Dynamic Mechanical Analysis (DMA). The analysis of variance
(ANOVA) is applied to measure the influence of the different factors such as RPW
concentration, temperature, frequency, and aging conditions on the RPW binders’ performance.
Marshall mix design was used for the preparation of asphalt mixtures. All the mixes were
prepared at 4% target air void content. The moisture susceptibility of the mixtures was also
evaluated using the retained Marshall stability test and tensile strength ratio. The evaluation of
rutting and fatigue performance of the asphalt mixtures were evaluated using a double punching
test at 60 °C and 20 °C, respectively. Finally, pavement performance of typical pavement
sections under different environmental conditions and traffic levels was predcited using the the
state of the art AASHTWOWare Pavement ME Design. Also, a comparative economic analysis
is performed in terms of initial material cost. The effect of incorporating sulfur into asphalt
binder formulation on the environment is also determined based on the results of the H2S/SO2
gases analyzer and leaching of metals into water tests. The estimation of the environmental
benefits of RPW modified asphalt is performed by comparing the carbon emissions and nonmethyl volatile organic compound (NMVOCs) of the various RPWs with the manufacturing
process of the same quantities of virgin LDPE and HDPE when used to modify asphalt.