الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
Recently, the quantities of waste materials and byproducts are increasing with the increase of construction projects, industrial activities, population growth, urbanization, development activities and changes in life style. Although these waste materials have negative effects on all surrounding areas, various types of them can be exclusively employed in civil engineering applications, especially in road construction. They can be used as smart alternative to the traditional materials which decreases the dependence on the depleted natural resources. The Mineral Filler (MF) which is an important ingredient in the hot mix asphalt (HMA) has a significant effect on its performance. This research investigates the feasibility of using waste materials (marble and granite) and byproduct material (steel slag powder) as alternatives to the conventional mineral fillers in HMA. In addition, the hydrated lime was also investigated in this research as it is typically used as an anti-stripping agent. Control asphalt mix with the traditional limestone filler was designed by Marshall method then, a replacement of the waste and byproduct materials was conducted. The laboratory testing program for the evaluation of the asphalt mixtures include moisture damage in terms of loss of stability and tensile strength ratio (TSR). In addition, five different HMA mixes were prepared, compacted, cored and sawed for dynamic modulus test. These samples were subjected to four different temperatures (4.4, 21.1, 37.8 and 54.4ͦ C) and six different frequencies (25, 10, 5, 1, 0.5 and 0.1 Hz). Moreover, the flow number test was performed on the same samples of the dynamic modulus test. Mastic samples with 1:1 filler to asphalt were prepared to evaluate the rheological properties. The samples were prepared using the different fillers and tested for penetration, softening point and Brookfield rotational viscosity (RV). Furthermore, the Transition Electron Microscope (TEM) on fillers and Scanning Electron Microscopy (SEM) on mastics were performed. Marshall results showed that mixtures containing waste marble yielded the highest stability. Moreover, it was found that the hydrated lime filler mix had the minimum value of loss of stability and the highest indirect tensile strength ratio. On the other hand, the steel slag powder did not improve the moisture damage resistance as compared to the control mix. The hydrated lime mastic had the highest softening point temperature and RV viscosity.
HMA mixtures were also designed to estimate the optimum asphalt content for each filler type and the cost of 1 m3 of asphalt mixture was simply calculated. The reduction in the total cost when the waste materials were incorporated as MF was about (6-10%), while the hydrated lime was 21% more expensive compared to the control mix. The hydrated lime mix yielded the maximum dynamic modulus (E*) and flow number thus it is expected to have a better rutting resistance. However, slag did not enhance the asphalt mix performance. Finally, the Quality-Related Specifications Software (QRSS) which is a simplification of the Mechanistic Empirical Pavement Design Guide (MEPDG) software was used to predict field performance of two different pavement sections with two different levels of traffic speeds and three climatic locations based on the predicted E* of the five mixtures. The simulation runs showed that all mixtures containing the different waste materials as mineral filler showed improved rutting resistance compared to the traditional limestone filler. However, the limestone was the best in terms of fatigue cracking resistance.