Khamad R. Assessment of Asphalt Concretes and Polymer Modified Asphalt Concretes Resistance to Aggressive Liquid Environments

The object of study - asphalt concretes and polymer modified asphalt concretes under stress and the effect of aggressive liquid environments. The purpose of the study is to establish consistency patterns of asphalt concrete and polymer modified asphalt concrete specimens destruction under comparable levels of loading. And On the base of those results developing a method allowing predicting durability level in conditions of influences both- aggressive liquid environment and mechanical loading. Methods of the research. The determination of physical and mechanical characteristics of the subject under study is performed by using standard methods of quality control. Durability characteristics are also determined under various schemes of destruction (compressing, indirect tension, bending) and the speed of deformation is estimated. Main tasks of the research where performed by methods and devices developed in the department of TRBM KNAHU and were used to determine corrosion resistance and the time it takes to destruct asphalt concrete specimens under simultaneous influence of the mechanical tension and aggressive liquid environments. Scientific novelty of the results: - for the first time theoretically and practically it is shown, that the optimal scheme of deformation to establish corrosion resistance of asphalt concretes and polymer modified asphalt concretes, which best corresponds to the road pavement working conditions is pure bending; - it is proven experimentally, that objectivity of destruction time comparative estimation of different specimens putted under simultaneous influence of the mechanical tension and aggressive liquid environment rises when we lower the degree of applied tension to 0,1-0,2 against its durability; - our concept of increasing by 10 to 15 % the optimal amount of binding material took further development, by determination of destruction time as criteria instead of using the results of the standard tests of compression; - for the first time it is experimentally established that polymer modified asphalt concretes with PMB, obtained by a direct insertion of the polymer into the bitumen, are more durable in aggressive liquid environment than polymer modified asphalt concretes on PMB base obtained by using a technique of mixing the bitumen with liquid mother solution of the polymer; - new experimental data is available about the action of Kation-surface active materials in relationship to durability of asphalt concretes and polymer modified asphalt concretes in liquid aggressive environments. Practical significance of the results lies in developed evaluation criteria of environmental resistance of asphalt concretes and polymer modified asphalt concretes, which notice its tension-deformed condition, and applying these criteria to predict destruction time of the specimens with different bitumen binder consistency and the amount and the method of modification by SBS polymer under various tensions. The results of this study constitute lie in the base of ISU 42.1-37641918-086:2013 "Road Pavement Asphalt Concrete. Durability Index Determination Method in Aggressive Environments" (Adopted and approved by order of Ukrainian Automobile Roads Agency on 25.12.2013, № 484).