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Ground Penetrating Radar

Application of GPR in Pavement Evaluations
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Benefits of GPR



Limitations of GPR



GPR Reports


Implementation of Ground Penetrating Radar (PDF 32 MB 29 pp)


GPR Summary (PDF 1 MB 5 pp)


GPR Video (MPG 117 MB)


For more information:


Shongtao Dai, Road Research


Matt Lebens, Road Research

Research Topics




This system can travel up to highway speed for evaluating pavement thickness

Ground-penetrating radar (GPR) is fast becoming a viable technology worldwide for surveying subsurface features and defects in flexible and rigid pavements.  GPR has the potential to be used for a variety of pavement applications, including measuring the thickness of asphalt pavement, base and sub-grade; assisting in the analysis of rutting mechanisms and locating subsurface objects.


GPR operates by transmitting short pulses of electromagnetic energy into the ground.  The reflected images of these pulses are analyzed using one-dimensional electromagnetic wave propagation theory.  These pulses are reflected back to the antenna with amplitudes and arrival times that are related to the dielectric constants of the material layers. 


Potential Applications of GPR


GPR Readout

Pavement Thickness Determination

Determination of pavement layer thickness is one of the more successful applications of GPR. For data collection at normal highway speeds, an air coupled antenna is attached to a vehicle, with a penetration depth of approximately 30 in. Experience has shown that GPR works well on flexible pavements (asphalt) where there is a strong dielectric contrast between layers, but may be less effective on rigid pavements (concrete) where the presence of moisture tends to attenuate the radar signal, or where the contrast between layers is minimal such as between concrete and granular base materials.