GPR profile of road section indicating components of base, subbase, and subgrade layers
Fig. 1. Blended 400 MHz and 1000 MHz ( top 5 ns) GPR profile from a highway in Finland shows base, sub-base and subgrade layers with interpretation. (upper) Topographically-corrected GPR shows new pavement and base course overlying old pavement, sub-base course with buried culvert, and subgrade poorly sorted glacial moraine. Moraine lower contact with bedrock is inferred.*
* Saarenketo, T., 2009, NDT Transportation, in Jol, H. M., ed., Ground Penetrating Radar Theory and Applications Amsterdam, Elsevier, p. 395-444.