Hot and cold recycling of bituminous mixtures

The useful life of an asphalt pavement depends on a number of factors. The most important ones are:.The volume and weight of the traffic.Weather.Quality of the materials.Subgrade strength.Drainage.Quality of Construction Due to the decrease in good quality sources of aggregate, the rise in hauling costs, the high cost of the equipment as well as the construction; during the last years apart from the conventional methods, significant changes have been witnessed in approaches concerned with the highway design, construction and particularly with the increasing interest in the matters of conservation of natural sources. This leads to the reuse of existing materials -recycling. With the rapid increase in the volume of traffic in Turkey as well as the increase of legal axle load to 13 tons, tandem axle load to 19 tons, a feasible solution is being searched during the last few years. In this study modern techniques for recycling have been described and laboratory experiments have been performed to see the usability of this method in Turkey.VI In chapter I of this five part study some definitions are given, information on the historical developments of recycling is provided, and reasons for preference are investigated. In chapter II a classification of recycling method is presented as hor and cold recycling ; in -situ and in plant. And also emphasis is placed upon the common equipment types that different countries use. In chapter III, laboratory tests are performed on the asphalt samples which have been extracted from the Ankara Street -an express way passing along the Campus of the Ege University in Bornova. Marshall Briquettes are prepared using the 20% and 30% of the old pavement, and stability tests are performed on each of the briquettes. In chapter IV, a cost analysis is made in visual-basic program to see the benefits and disadvantages of the recycling methods. In the last chapter of this study, the results that are obtained from the laboratory tests and visual basic program are summarized. Not only the disadvantages and advantages but also the usability of this method in Turkey is discussed.