The Effects of mixture variables on mixture performance and establishing a model to estimate the service life

The continuous increase of demand to the highways, developments vehicle technology, the effect of heavy traffic loads and negative impacts of climate conditions damage on the highways before the end of expected service lives. There are numerous factors, that cause damages on the highways so it will be beneficial to check "Service Life Estimated Methods", which have been in our country to date once more. In this study, the rotten parameters (fatigue cracks, rutting or permanent deformation etc.) which are being used in some countries to evaluate the performance of asphalt layers are presented. By using the theatrical knowledge, which was provided by examining the related literature, the experiments which are presented in the following sections are being executed. As a result, such a method was achieved that some very important knowledge is given about the estimation of service lives of the asphalt mixtures. A summary regarding these studies are presented below. Marshall Design, Indirect Tensile Strength Test, Indirect Tensile Test, Static Creep Test and Repeated Creep Test were performed on both conventional and modified mixtures during laboratory studies. A sample experimental studying program was prepared to point out the effects of mixture variables on the elasticity and creep moduli, which serve as an important indicator on the evaluation of service life and evaluate the performance of mixture. Moreover, a rutting estimation model for our country was determined among several fatigue performance evaluation models. In this way, it will be possible to estimate the rutting and fatigue performances of the mixtures. Nowadays asphalt is being modified by some additives and most probably the usage of these additives will be more common in the near future. In order to evaluate the modified mixtures, prepared by using additives in the mixtures or binders, by the model presented in this thesis; Vestoplast additives was used. By using Vestoplast, some modified mixtures were produced and it was made to serve as an addition variable. The remarkable point here is not the type of additive, but the possibility of modifying asphalt by using some different materials. By the results obtained from the experiments, the effects of mixtures variables on mixture performance were evaluated, also a model established to estimate the service life, This model was so prepared that it will be possible to add some more variables as a result of future studies, which will let more precise service life estimations even without any experimental studies.