الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Asphalt recycling techniques have been around for over a century. Cold recycling operations started in the early 20th century, then after roughly 25 years, the Hot in-place recycling followed by. In the ’70s, two events animated the boom of asphalt recycling development, the oil crisis in the early ’70s and the evolution of large-scale cold planing equipment in 1975. Since then, asphalt recycling techniques kept on developing. Public awareness also affected the development of asphalt recycling. By law, a specific percentage of the construction/rehabilitation materials must be/include recycled materials. Due to these efforts, asphalt pavements are one of the most recycled materials worldwide. This thesis provides a review of the most common asphalt recycling approaches. The study discusses the procedures of recycling projects including project assessment, mix design, and construction. Cold planing, Hot recycling, Hot in-place recycling, Cold recycling, and Full-depth reclamation are briefly explained in the study. State-of-the-art techniques, software, and equipment have been indicated in the study presenting their influence on the demonstrated approaches. Detailed project procedures have been discussed separately for each treatment and critical details in procedures are highlighted to ensure the full comprehension of the procedures and the consequences. For a deeper investigation, the rehabilitation selection process has been discussed considering the technical aspects along with environmental concerns and economic analysis. The study reviews the evaluation of pavement maintenance projects and the rehabilitation selection process starting with the assessment of pavement defects and manipulation of available data. Assessment of pavement properties is then demonstrated along with the determination of distress causes and preliminary rehabilitation selection. Detailed project analysis steps are explored for the recycling techniques separately before completing the selection process with the environmental and economic analysis. The thesis provides a preliminary finite element modeling of asphalt concrete materials. The study discusses the impact of modeling asphalt as a viscoelastic material versus as an elastic material. Two models (elastic and viscoelastic) have been studied to pursue the progress of stress and displacement under static and dynamic cyclic loading. The results illustrated the effect of viscosity as the viscoelastic model experienced lower stress values and higher displacements due to energy dissipation and time dependency. A RAP mixture model is studied and the responses were compared to conventional HMA. The comparison illustrates the impact of RAP inclusion in asphalt mixtures as it increases the stiffness of the mix. The higher stiffness results in higher stress values and less susceptibility to spatial variations. ABAQUS software has been used to model and analysis the two prescribed models. A sensitivity analysis was conducted to ensure the validity of the results and their independence of boundary conditions effects. The study demonstrates the need for accurate material modeling to obtain reliable results. The results of the study agreed with the other researches discussed in the literature review, which assures the validity and the creditability of the proposed work.