Skid Resistances Skid resistance is the force developed when a tire that is prevented from rotating slides along the pavement surface. Skid resistance is an important pavement evaluation parameter because:
Inadequate skid resistance will lead to higher incidences of skid related accidents.
Most agencies have an obligation to provide users with a roadway that is “reasonably” safe.
Skid resistance measurements can be used to evaluate various types of materials and construction practices
Ground-penetrating radar (GPR) GPR is a geophysical method that uses radar pulses to image the subsurface. This nondestructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures. GPR uses high-frequency (usually polarized) radio waves, usually in the range 10 MHz to 2.6 GHz. A GPR transmitter emits electromagnetic energy into the ground. When the energy encounters a buried object or a boundary between materials having different permittivity, it may be reflected or refracted or scattered back to the surface. A receiving antenna can then record the variations in the return signal.
Ground-penetrating radar antennas are generally in contact with the ground for the strongest signal strength; however, GPR air-launched antennas are also now a days used above the ground to increase the speed of data capture when mounted on a vehicle. We have tied up with a reliable and reputed agency from Italy, for carrying out the GPR (Ground Penetrating Radar) surveys for detecting underground utilities using 400 to 900 MHz antennas and for measuring the pavement thickness using 1 or 2 GHz horn antennas mounted on a vehicle, providing accuracy up to 2 mm.
The system is interfaced with video-camera to provide continuous video data for correlating radar data with visual info for identifying the locations. The data capture is very fast and can capture about 100 Km of pavement data in one day.