The report deals with issues of road bitumen non-conformity to Kazakhstan's sharpcontinentalconditions.Based on the analysis of air and asphalt pavement maximum and minimum temperatures,in recent years the bitumen requirements for different country regions have beensubstantiated as well as zoning as to the performance temperatures has been developed.The results of investigating the high-temperature stability of a number of bitumens with J.Bari, M. W. Witczak correlation model as well as their low-temperature stability using BBR(bending beam rheometer) have shown that they meet the requirements only for a smallpart of the Republic’s territory.In recent years, a number of polymer additives introduced both into bitumen and asphaltmix have been checked in situ: Kraton, Elvaloy, Sasobit, Butonal, TAFPACK-Super (TPS),TPS-F, etc. It has been found that at their introduction into bitumen, the low-temperatureproperties of polymer-modified bitumen either do not change or change insignificantly (forElvaloy about 2°C per 1% of polymer) whereas their thermal resistance growssubstantially: for each one percent of the introduced additive the increase is approximatelyby 6°C for Kraton, by 14°C for Elvaloy, and 9°C for Sasobit. These results are in goodagreement with the actual pavement condition.
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