Viscoelastic Modeling and Field Validation of Flexible Pavements

TLDR

The study aims to characterize hot‑mix asphalt viscoelastic properties at intermediate and high temperatures and embed laboratory‑derived parameters into a 3‑D finite element model to simulate pavement responses to vehicular loading across temperatures and speeds. The authors developed a 3‑D finite element viscoelastic model, calibrated with lab data, and validated its predictions against field measurements from the Virginia Smart Road. Compared with an elastic model, the viscoelastic finite element model more accurately reproduces field responses, reducing prediction error to under 15 % and capturing transverse retardation, longitudinal relaxation, permanent deformation, and partial rut recovery.

Abstract

The objective of this study was to characterize hot-mix asphalt (HMA) viscoelastic properties at intermediate and high temperatures and to incorporate laboratory-determined parameters into a three-dimensional finite element (FE) model to accurately simulate pavement responses to vehicular loading at different temperatures and speeds. Results of the developed FE model were compared against field-measured pavement responses from the Virginia Smart Road. Results of this analysis indicated that the elastic theory grossly underpredicts pavement responses to vehicular loading at intermediate and high temperatures. In addition, the elastic FE model could not simulate permanent deformation or delayed recovery, a known characteristic of HMA materials. In contrast, results of the FE viscoelastic model were in better agreement with field measurements. In this case, the average error in the prediction was less than 15%. The FE model successfully simulated retardation of the response in the transverse direction and rapid relaxation of HMA in the longitudinal direction. Moreover, the developed model allowed predicting primary rutting damage at the surface and its partial recovery after load application.