Testing and analysis of viscoelastic characteristics of solidifying concrete pavement slabs

Abstract

To accurately estimate the tensile stress distribution in concrete pavement slabs, their viscoelastic characteristics must be clearly identified, because in a drying concrete slab, creep and stress relaxation occur in a complex manner over a long time. In this study, a restrained ring test was conducted to determine the viscoelastic characteristics of a concrete pavement slab. Finite Element Analysis (FEA) was performed to simulate the restrained ring test using the solidifying viscoelastic properties obtained from the modified elastic-viscoelastic correspondence principle to verify the effect of the viscoelastic material properties. The tensile stress calculated by the viscoelastic analysis was observed to be ∼50% of that obtained from the elastic analysis. The FEA was performed under assumed environmental conditions for the elastic and viscoelastic models of a concrete pavement. Further, the maximum tensile stress based on the viscoelastic model was observed to be 45–55% less than that based on the elastic model owing to stress relaxation. It is concluded that the model that considers the solidifying viscoelastic properties shows better analysis results for tensile stress distribution in a concrete pavement. With better and more accurate estimates of the concrete pavement responses, a pavement that is more structurally sound can be designed.