An innovative ground-penetrating radar technology has enabled researchers to identify damage of municipal underground infrastructure caused by Hurricane Katrina more than a decade ago.
The system, based on novel ultra-wide band (UWB) pulsed radar, has been developed by engineers from Louisiana Tech University, USA. Mounted on pipe-inspecting robots, the radar detects fractures, quantifies corrosion and locates cavities in the surrounding soil caused by leaks and flooding. The engineers, in the comfort of their offices, receive data in real-time.
The Louisiana Tech team tested the technology in the city of Slidell, which was badly hit by Hurricane Katrina in 2005. Although the surface damage was cleared and repaired long ago, the city authorities had, until recently, only limited tools to properly examine what the storm surge caused in the underground.
"While we were aware of the depth and breadth of the problems that plagued our underground utilities, and we knew surrounding communities had experienced similar problems, I believe it wasn't until we made the trip to Ruston (where Louisiana Tech is based) in 2010 and then saw the results of the UWB investigation that we actually realised we could have quantifiable evidence of the scope of that damage," said Jay Newcomb, City of Slidell Council Member and Louisiana Tech alumnus.
Arun Jaganathan, associate professor of civil engineering and construction engineering technology at Louisiana Tech, began developing the novel radar as a basis for his PhD dissertation research. Over the years, he created a complete package with 3D-rendering capabilities, signal processing and electronics, that municipal engineers can use for routine pipeline-condition assessment.
"This technology is unique in its capability to generate high-resolution images, which allow engineers to inspect a particular spot in detail," Jaganathan explained. "The radar system emits ultra-short electromagnetic pulses from inside of a sewer pipe and captures the signals back-scattered from the pipe to determine the condition of various layers hidden behind the wall which we cannot directly see using visual tools such as a camera.”
Slidell authorities praised the cooperation with Louisiana Tech, which has helped the city devise a plan and secure funding for a large-scale underground utility restoration.
"We have almost two whole budgets to spend on streets, drainage and sewer tanks,” Newcomb remarked.