Analytical modelling of visco-elastic behaviour of hot-mix asphalt

Abstract

As part of the revision of the South African Pavement Design Method (SAPDM), laboratory testing was conducted to obtain the dynamic (Complex) modulus |E*| of hot-mix asphalt (HMA) samples. Dynamic modulus gives an indication of linear visco-elastic (LVE) behaviour of HMA materials at different temperatures and loading frequencies; and is required for computation of stresses, strains and displacements in flexible pavement analysis and design. Laboratory tests to obtain dynamic modulus are normally conducted at limited range of temperatures and loading frequencies. In order to characterize HMA mixes for pavement analysis, sigmoidal function master curves are constructed at different temperatures and loading frequencies using a time-temperature superposition principle.