RESISTANCE TO PERMANENT DEFORMATION OF THE TLA-MODIFIED MASTIC ASPHALT MIXTURE BASED ON STATIC AND DYNAMIC INDENTATION

Mastic asphalt mixture (MA) has been particularly popular in recent years for bridge pavements due to many advantages, such as easy application, good waterproofing properties and high durability. However, the drawback of the mastic asphalt mixture in comparison to other asphalt mixtures is its lower resistance to permanent deformation. Additive, such as natural asphalt Trinidad Lake Asphalt (TLA) is often applied to make the mastic asphalt mixture resistant to permanent deformation. Practical experience demonstrates that serious failures may occur if MA pavement design and materials selection is not taken into account sufficiently. Therefore, in this study, the influence of two parameters: the TLA content and bitumen-filler mastic composition described by the filler-binder ratio (f/b), on the rutting resistance of the MA mixture, were evaluated. The rutting resistance of the MA mixtures was evaluated on the basis of static and dynamic indentation tests. Both parameters showed a high correlation with the rutting parameters. The mathematical relationships can be used for the prediction of MA composition in such a way that the final MA mixture meets the relevant requirements of the rutting resistance.