3-D technology in use for Route 15 upgrade

As the state Department of Transportation continues work along Route 15 near South Williamsport, it has implemented a digital, 3-D technology to make the design process of the $11 million project more efficient.

PennDOT used digital photogrammetry, which takes digital photos of a terrain to create a 3-D model of it, to plan for the project.

“A digital camera is used at different locations with the digital photos overlapping,” explained Bob Johnson, district geotechnical and pavement design engineer. “Where the photos overlap, this creates a 3-D image.”

Computer software then converts the data from the photographs into geological measurements.

The process – which Johnson explained has been used near Pittsburgh in a project this year – allowed PennDOT to have a more accurate model and better plan for cutting back the mountain side.

In addition to a better model, PennDOT also saw cost – about $25,000 worth – and time savings by using the technology.

As for time, taking the photographs took one day. The previous method could take anywhere from 20 to 50 days to complete.

“There is a large time saving from this method, as the number of readings that can be obtained in one day of digital photos would require weeks of manual readings,” Johnson said. “The potential for human error is reduced as measurements are collected electronically.”

PennDOT also saw the added benefit of safer conditions for workers with the new technology.

“The previous method required people to manually take the readings with a Brunton compass, which required people to physically be on the slope,” Johnson said. “This creates unsafe conditions from falling down the slope or being hit by falling rocks. With the digital method, the operator can stay safely away from the slope and take the digital photos.”

The technology is being used in another project, which is in the design process.