الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The centrifuge extraction method is primarily used in Egypt for quality control purposes to monitor bitumen content and aggregate gradation. In this method, solvents are used to dissolve bitumen from asphalt mixtures. These solvents have negative impacts on the operator’s health and the environment and are considered environmental hazardous wastes. Alternatively, the ignition furnace test method stated in AASHTO T 308 can be used to calculate bitumen content by subjecting a loose asphalt mixture sample to relatively high temperatures that cause the bitumen to ignite. The ignition furnaces are environmentally friendly, as they are equipped with afterburners to convert any pollutants into harmless combustion by-products. However, the extreme conditions inside the ignition furnace chamber cause some aggregate mass loss. To overcome this problem, the procedure states that prior to any testing, correction factors for bitumen content and aggregate gradation must be determined per design mix and ignition furnace used by preparing and testing two correction samples identical to the design mix. These procedures are considered time consuming, and limit the use of the ignition furnace test method to asphalt mixtures of known materials and design mixes, which is not the case in the centrifuge extraction method.
The research in this thesis began by addressing the dependability of the ignition furnace method versus centrifuge extraction on the most common asphalt mixtures used in Egypt. The next step aimed to identify the different factors affecting the ignition furnace correction factor. The following step monitored the effect of the ignition test on the absorption, disintegration, and specific gravity properties of the coarse aggregates. The final step aimed at developing a model which could accurately calculate the correction factor based on the experimental results to allow the application of the ignition furnace test for testing asphalt mixes of unknown materials.
Results were analyzed statistically and showed that the ignition furnace method can replace the centrifuge extraction method using local materials after applying correction factors to ignition furnace results.