Developing a Forecasting Model of Asphalt's Rutting Potential Using Gyratory Compactor Parameters

Rutting is one of the most important kinds of flexible pavements’ deformation which annually consumes significant amount of maintenance and repairing costs of asphalt pavements. On the other side, in level one of Superpave’s mix design method that has outstanding vantages compared to the Marshal method, there is lack of a simple test to determine the sample resistance against permanent deformation which is the main reason of rutting in asphalt. Available evaluation methods of rutting potential of asphalt mixtures are often expensive and time consuming. For these reasons, there is a need to present an accurate method to determine the samples’ rutting condition in a short time and with low costs. In this research, two different types of lime and silicon aggregate, two types of grading, two types of bitumen, two types of filler and three different bitumen contents have been used to provide samples. After the Gyratory Shear Stress Modeling, using the model’s parameters and gyratory compactness’ slope, two mathematical models have been developed for determination of sample’s permanent deformation. These models have been validated using Genetic Algorithm and Artificial Neural Network and can evaluate asphalt rutting potential simultaneously as the asphalt samples are provided to determine the optimum bitumen content. Therefore, there is no need to provide expensive rutting test’s apparatus and also the time to present an appropriate mix design will be reduced to