Effectiveness of wax additives in cast asphalt concrete mixtures

Building Materials
Authors:
V.V. Yadykina O.A. Mikhaylova A.I. Karlina N.I. Vatin N.V. Martyushev
Abstract:

The use of cast asphalt concrete mixtures makes it possible to produce road surfaces with very high wear resistance and water resistance. One of the problems of using cast asphalt concrete mixtures is the need for high temperature of their preparation. This significantly increases energy costs, worsens the labour conditions of workers and negatively affects the environment. Therefore, it is very important to search for effective methods to reduce the temperature of production of cast asphalt concrete mixtures without deterioration of their performance characteristics. One of the promising solutions to this problem is the use of synthetic waxes as additives that change the rheological properties of bituminous binder. Besides, the use of additives based on synthetic waxes makes it possible to improve the resistance of asphalt concretes to plastic deformations, which is very important for cast asphalt concrete pavements. In this paper, changes in the physical and chemical properties of bitumen binder modified with a new complex additive Viskodor PV-2 are investigated. In order to evaluate the effectiveness of this additive, these changes were compared with those observed when the well-known wax modifiers Licomont BS-100 and Sasobit were introduced into bitumen. The effect of these additives on the properties of cast asphalt concrete was also studied. It has been established that the introduction of 2.5% of the investigated additives allows reducing the temperature of paving of cast asphalt concrete by at least 30 °C without reducing its strength characteristics. It is revealed that the use of Viscodor PV-2 in the composition of cast asphalt concrete contributes to the increase in the value of workability with a simultaneous decrease in the index of the die indentation depth. It is established that the efficiency of Viscodor PV-2, used as an additive to reduce the temperature of preparation of cast asphalt concrete mixtures, is not inferior to the known waxes Licomont BS-100 and Sasobit.