Prediction of Low Temperature Properties Using Dynamic Rheological Properties of Asphalt at Intermediate Temperature

The low temperature properties of asphalt were characterized by static and dynamic load. The bending beam rheometer (BBR) was developed to measure low temperature creep properties of asphalt within limited time, otherwise the measured deflection will exceed the BBR measure limit. At low temperature, asphalt nearly exhibit ideal elastic behavior or behave as viscoelastic solid. Slip or break was caused by small adhesion between the sample and plates of dynamic shear rheometer (DSR). Consequently measurements may produce errors which can not be eliminated by any calculations, but can be avoided at intermediate or high temperature. It is well known that all linear viscoelastic material functions are mathematically equivalent and each function contains essentially the same information. Therefore, a linear viscoelastic material function can be converted into other material functions through appropriate mathematical operations. Samples of asphalt were tested by DSR at intermediate temperatures and high temperatures and BBR at low temperature. The dynamic rheological properties at intermediate temperature were converted to dynamic rheological properties and static creep properties at low temperature using the time temperature superposition principle (TTSP) and the transformation relation between static and dynamic functions, which was compared with the result of BBR. In this study, good correlations were found between the calculations results from DSR and the measurement results of BBR. In accordance with these findings, DSR data at intermediate can be used to predict the low temperature behavior of asphalt. This finding is especially important for asphalt. It might offer a relatively simple and accessible experimental technique to study the low temperature properties of asphalt. Therefore, we can obtain viscoelastic properties over a much larger time or frequency range than measurement results at low temperature.