August 10th, 2012
GROUND PENETRATING RADAROptimize Mobility, Preserve Infrastructure, by Catherine Higgins.
The Federal Highways Administration is sponsoring demonstrations of a new technology that uses radar to analyze pavement.
The new technology can help determine the remaining service life of pavement without using invasive means. Testing is necessary to find out what conditions are causing pavement deterioration, and then to determine the right course of action to take to preserve or replace the pavement.
Typically, engineers determine the remaining service life pavement by drilling core samples. Coring pavement takes time and resources to extract , transport and then test the pavement. Coring is also an inconvenience for the traveling public since lane closures are required for the work to take place.
Ground Penetrating Radar can provide a close and detailed look at pavement without the time, expense lane closures required by coring.
GPR technology uses radar to create a cross sectional analysis of the pavement under the surface. The equipment is mounted on a regular vehicle that can move with traffic, so no lane closures are required. While coring gives snap-shot looks at pavement condition.
In one sweep, GPR can collect enough information to have a comprehensive view of the pavement, including density, material variation, degradation due to stripping or other factors, and thickness. The data collection method works on concrete or asphalt and is “a better way to diagnose the problem,” according to Tom Yu, Senior Pavement Design Engineer with FHWA.
Although GPR is a great diagnosis tool for pavements that need rehabilitation, Yu sees other opportunities as well. “For me, the most promising area is construction [quality and assurance] testing.” Yu visited UDOT Region Three recently with a GPR equipped van and spoke at an Intelligent Compaction Demonstration. He will take the van on the road to collect data so he can demonstrate the usefulness of the new technology. “It needs to show its own value” before the pavement data collection method is widely adopted.