Influence of rest period on asphalt recovery considering nonlinearity and self-heating

Abstract

This paper presents investigation on the recovery potential of hot mix asphalt (HMA) mixture using cyclic uniaxial tension-compression test in stress-controlled mode. The recovery potential and its dependence on rest period duration were investigated taking into consideration nonlinearity and self-heating effects observed during cyclic loading. In order to preserve the internal specimen’s structure a small-size temperature sensor was embedded into asphalt mixture during compaction. It is found, that the effect of nonlinearity on complex modulus recovery is relatively small and that it is not affected by increasing duration of the rest period. The effect of temperature variation in the core of the specimen occurring during cyclic excitation and rest periods has a significant influence on HMA recovery properties. Self-heating results in a much more rapid recovery of complex modulus than other eventual side effects, such as thixotropy, self-healing and strain relaxation. This effect vanishes when temperature reaches its original value, leaving to the other biasing phenomena dominant in terms of complex modulus recovery.