Finite Element Analysis of Surface Wave Radiation for Pavement Debonding

A large scale finite element model with high mesh resolution is established to simulate the ground truth of regular highway pavement structure with subsurface debonding defects. The simulation is motivated by non-destructive testing methods that derive information from the acoustic radiation of the surface wave. These NDT (Non-Destructive Testing) signals come from solid elastic wave propagation beneath pavement surface, which then couple with acoustic wave in air above the pavement surface. In this article, 2 main debonding phenomena, which are conventionally hidden below the pavement surface, are modeled and also compared with a healthy (perfectly intact) pavement structure model. Both the impact-response transient analysis and frequency spectrum analysis have been given to show a new opportunity to detect the subsurface debonding in pavement non-destructively through acoustic signals from heights above the pavement surface which are incorporated with ground truth information.