Ground Penetration Radar (GPR) is a powerful, reliable and high performance nondestructive testing tool for solving various kinds of engineering problems related to geotechnical site investigation, construction, and maintenance of highways and bridges. It has been increasingly utilized for the management of highway infrastructures such as road pavements and bridges on a network level which requires condition assessment and deterioration modeling. GPR can determine the layer thickness and estimate moisture content of the in-situ soil underlying the pavement. It has a promising future because of its efficiency, quality, and non-destructiveness. GPR provides reliable and significant information to pavement condition evaluation that is very useful to predict the pavements structural capacity and performance. This will further help improve pavement maintenance and rehabilitation strategies, and in the long term, it provides rationalities in allocating funds. GPR in combination with other nondestructive evaluation methods such as Falling Wheel Deflectometer (FWD) or Rolling Wheel Deflectometer (RWD), can provide complete data for pavement layer thickness, deflection and elastic moduli for the mechanistic pavement performance prediction model. However, the application of GPR in highway engineering is limited because of our incomplete understanding about the dielectric properties of highway materials. This paper presents the state-of-the-art GPR applications in highway infrastructure condition assessment and future development. It also highlights the possible integration of GPR with other nondestructive testing methods and its development for the network-level pavement management system. Finally, limitations and issues related to further investigation of the GPR improvement are discussed.
Samenvatting