Critical temperature stress evaluation in asphalt pavements

摘要

Daily variation of temperature T{t) in asphalt pavements is non-linear with time (t). Irrespective of temperature variation, the developed temperature stress (σ(t)) varies non-linearly with t, due to the viscoelastic behaviour of asphalt material. In viscoelatic materials, a{t) can be evaluated as an integral function of time. While integrating for stress evaluation for an intermediate day, specifically during the winter, one has to adopt an initial hour of the T(t) profile. It is questionable which initial hour of 7(0 provides the critical stress situation, while taking into account: (a) a non-linear temperature variation; (b) the effect of previous stress history; and (c) the stress relaxation with time. This paper critically examines the initial conditions of the 7(0 profile for critical stress evaluation, which is of primary concern for thermal cracking prediction. This paper also presents a parametric study on the temperature stress.