Ground penetrating radar (GPR) can be used as a tool for assessing the condition of the pavement structure at locations of surface distress, as well as identifying locations of previous subsurface maintenance activities that are not visible at the surface of the pavement.

In assessing the existing condition of a pavement structure, locations of past maintenance activities are often overlooked, or concealed by rehabilitation activities such as mill and overlays. Potential problem areas may not be evident at the time of evaluation, and if ignored could increase the rate of deterioration of the pavement structure. Proper identification of potential problem areas could provide a more accurate assessment of the existing pavement condition and better understanding of the performance of a pavement structure. Understanding the deterioration of a pavement structure, will in turn allow owner agencies to calibrate forecasting tools in their pavement/asset management systems.

Combining a GPR survey with traditional pavement condition investigations techniques usually proves to be beneficial for pavement evaluation. The results of a GPR survey provide valuable information by identifying subsurface problem areas, areas of previous full-depth and partial-depth repairs.

  • Identify the location of cores/boreholes relative to buried pavement structures, especially when advanced through previously repaired areas whether or not they are evident from visual inspection of the pavement surface.
  • GPR may also be used in advance of coring to select optimum coring locations.
  • GPR can differentiate between full-depth asphalt repairs, or partial depth asphalt repairs
  • Locate and measure depth of reinforcing steel in concrete.
  • Identify joints and cracks in the underlying pavement slab.
  • Show boundary of the bottom of asphalt and the top of concrete.
  • Concrete thickness can often be determined, but less accurately than the asphalt.
  • Locate cracks that are not visible at the surface from conditions surveys that may indicate future problem areas.
  • Measure pavement lay thickness comparable to core results.

GPR Roadway Analysis can form a valuable part of a comprehensive and cost effective maintenance program.

Contact us for further information on the benefits of GPR roadway surveys and specific proposals.