Surveys

High Speed Surveys

HDS are at the forefront of asphalt laser surveying, having developed systems that directly replicate volumetric patch texture and rolling straight edge tests. Our laser systems are vehicle mounted, removing technicians from harm’s way and delivering high-quality accurate testing from the safety of a vehicle. HDS also provides advanced surveying capabilities for measuring road surface characteristics during the asset lifecycle, including SMTD, MPD, and IRI.

Traffic Speed Surveys

Highway Data Systems have a number of surveying capabilities including:

  • Surface macrotexture - volumetric patch / sand patch /glass beads test equivalent
  • Surface profile (rolling straight edge equivalent)
  • International Roughness Index
  • Sensor measured texture depth (SMTD) and Mean Profile Depth (MPD)

Surface Regularity and Surface Macrotexture

The HDS laser survey systems directly replicate the volumetric patch test for asphalt surface macrotexture and the rolling straight edge test for asphalt surface profile. These two tests are currently undertaken using traditional manual methods which pose a serious risk for the people doing them and which deliver unreliable and undigitized report data.

The rolling straight edge equivalent laser is a single point red laser which measures, over a 12ft section, the surface linear profile of an asphalt or concrete road surface. The HDS texture laser operates by inverting the usual texture equation whereby a known volume of either glass beads or sand is spread out over an asphalt surface and the diameter of the resulting circle is measured to infer the surface macrotexture.

The HDS blue laser system is approximately 8in. wide and, by travelling longitudinally along the road surface measuring at 62,000 times per second, calculates the volume of the surface. Research funded by National Highways has demonstrated equivalence between the conventional and HDS methods and HDS now operate the laser system on a number of sites on the Strategic Road Network, the Transport Scotland Trunk Road, and several UK local authority sites.

Please contact HDS for more details.