Minnesota Department of Transportation

511 Travel Info

Road Doctor

Advanced, integrated testing and data processing

What is it?

The Road Doctor Survey Van (RDSV) is one of the modern, integrated and the most advanced nondestructive road survey technologies currently being investigated by MnDOT’s Office of Road Research & Materials. The RDSV can provide continuous and complete roadway information by  integrating  state of the art hardware for pavement data collection and advanced software for processing, synchronization, and visualization of the data. The hardware components include Global Position System (GPS) referencing systems, Distance Measuring Instrument, Ground Penetrating Radar (GPR), Thermal Imaging Camera, Laser Scanner and Video Cameras (see picture).

The software offers remarkable data processing and tabulation tools for the data collected from the RSDV, as well as for data imported from third-party systems such as Falling Weight Deflectometer (FWD), Traffic Speed Deflectometer (TSD), 3D-GPR Radar and Pavement Management System (PMS) Database to provide a complete road structure and condition information. Furthermore, the software links and synchronizes all the data through temporal and spatial reference points and visualize in formats that are easy to interpret (insert picture)
What type of information it provides

Some of the primary road and surface information obtained from the RSDV include:

  • Transversal and longitudinal rutting profiles
  • Layer thickness
  • Layer strength and moduli
  • Point-cloud laser transversal and longitudinal
  • Roughness measurements
  • Pavement surface imaging, and video logging data
  • Moisture monitoring using GPR Frequency Response
  • Pavement cross fall
  • Pavement settlement
  • Ditch and shoulder failures

What are its potential applications?
MnDOT recently acquired all the components of the RDSV from the Road Scanner. Staff from the research office is currently working to assemble and install all the items in a new survey van. Activities included in the near future are:

System validation: The testing system will be used to conduct focused field testing operations aimed to validate the technology, ensure the measurements meet available MnDOT specification (i.e., IRI for roughness), and explore benefits and potential applications.

Project scoping application: The research office will work with district and resident engineers to develop effective RDSV testing programs for structural and functional evaluations of pavements, tools for aiding the selection of appropriate rehabilitation strategies, and guidelines for load restrictions based on moisture in the pavement system

Research applications: The 3D GPR radar will be incorporated into the RDSV and to further advance the ongoing research on using the full-lane GPR technology to detect delamination and stripping in asphalt pavements.