With the implementation and increased use of automated machine guidance equipment and global positioning on Oregon Department of Transportation construction projects, physical staking is becoming a thing of the past.
As part of this evolution, construction inspectors need tools that allow them to perform quality checks without the visual clues provided by traditional construction stakes.
Increasing Accessibility and Efficiency
ODOT has deployed survey-grade GNSS tablets to its construction inspectors, providing them with access to the same data and information used by the machines constructing the roadway. With these tablets, inspectors can easily determine line and grade on a construction site.
These tablets use the Oregon Real Time GNNS Network (ORGN) to achieve accuracies of +/0.07 ft. MicroSurvey Field Genius surveying software is used to directly read XML design files. This allows an inspector to work with the same roadway design files as the contractor, and do so with a high-degree of accuracy.
The goal of this initiative is to give inspectors the capability and flexibility to conduct the same checks required for projects using traditional staking methods. It is not to make an inspector into a surveyor.
Inspector Tablet Pilot Project
ODOT's use of inspector positioning tablets is fully implemented, with 60 tablets deployed across the state. Prior to receiving a tablet, construction personnel must complete a one-day training session. Approximately 200 construction staff members have been trained. The tablets have been successfully used on many projects statewide since the fall of 2015.
DT Research tablets were selected by ODOT to provide rugged Windows-based touchscreen tablets. The purchase price of the necessary hardware and software is estimated at $8,500, a savings of approximately $12,000 over standard survey-grade GNSS units.