In early April, Infrasense conducted a non-destructive survey and report for 10 lane miles of a section of Route 2, in Rhode Island. The project provided the client with 4 sets of data showing where concrete appears to be present under the asphalt pavement versus an aggregate base. The survey was conducted at driving speed with no closures, no disruption to traffic, and zero impact to the integrity of the road.
The GPR data collection system included a pair of 1 GHz horn antennas and a SIR 30 control unit, both manufactured by GSSI in the United States. The final report included a quantitative table of segments or roadway defined by mile posts along by 4 different wheel paths, along with visual plots showing the structure type along the 5- mile stretch.
The GPR pavement surveys are carried out according to ASTM D4748-10. The resulting data shows a cross-sectional slice of the pavement strata at various offsets. Each slice includes the surface, and any material change in the first few feet below the surface.