Home Natural Hazard Management 3D mapping documents Hurricane Sandy’s aftermath

3D mapping documents Hurricane Sandy’s aftermath

US: Rutgers University has embarked on a geospatial mapping project to collect 3D images of the Hurricane Sandy-ravaged areas to help plan a smart recovery. A blue van meandered through the Sandy-ravaged areas of Ocean County for this purpose.

Unlike the human eye or photographs, these images can detect minute fractures in the roadbed that could spell trouble for the infrastructure below if water gets in and freezes. They can determine if utility poles are leaning even slightly, alerting power companies about which ones to replace before the next storm.

They even see through debris piled high against structures to see if a building is off its foundation — even by a fraction of an inch.

“You can take pictures, but it’s still nothing compared to 3D,” said Jie Gong, an assistant professor at Rutgers School of Engineering. With this, he said, “you can see every nook and cranny.”

The technology, called geospatial mapping, has been around for at least a decade, and used regularly to analyse roads when companies want to move wide loads or locate hindrances such as trees or overhead wires. But this is the first time this technology is being used in New Jersey to collect data on such a wide scale after a major storm, Gong said.

“We’re going to try to use it as a resource to plan the reconstruction,” he said.

Rutgers decided on its own to team with the Richard Stockton College of New Jersey and Ohio-based Woolpert Geospatial Mapping Co. to do the work recently in Toms River, Lavallette and Seaside Heights.

Engineers gather the 3D image by first setting up a tripod with a receiver on top. As Woolpert technician drives a van at 15 mph along a local road, a laser is emitted from a device on top of the van. The light bounces off the targets, such as buildings — and goes to the receiver. The receiver sends the information back to equipment on the van.

The equipment on the van collects 1 million data points per second, which form images on technician’s computer screen. Since the images are caught by laser light, not even the high mounds of trash at the curbs can block the buildings because the 3D images can be turned to be viewed from the top, sides of below.

Source: NJ