Elastic and viscoelastic back-calculation of pavement layers’ moduli using data obtained from traffic speed deflection devices
Arman Hamidi, Inge Hoff, Helge Mork
Abstract
In this study, pavement layers’ elastic moduli obtained from different deflection devices were compared. This was based on measurements with the Falling Weight Deflectometer (FWD), Traffic Speed Deflectometer (TSD) and Rapid Pavement Tester (Raptor) at four road sections in the Norwegian road network. An elastic back-calculation software system called EBS was introduced to compare the results. Also, a new viscoelastic back-calculation procedure was performed on TSD data using the ViscoRoute software. The findings of this study demonstrate the limitations of the elastic approach in capturing the viscoelastic characteristics of pavement layers. The proposed viscoelastic back-calculation procedure marks a preliminary effort to integrate dynamic modulus calculation into the Pavement Management System, potentially leading to more cost-effective maintenance strategies. • TSDD deflections can be converted to equivalent FWD deflections. • ViscoRoute can be used for viscoelastic back-calculation of layers’ moduli. • Layers’ moduli obtained from elastic and viscoelastic approaches are different. • Dissipated energy due to viscosity is not reflected in elastic back-calculation. • New procedures for estimating layers’ moduli from TSDD data need to be developed.