Paving’s next steps: Intelligent compaction and thermal profiling

First published at CONEXPO-CON/AGG - March 13, 2020

Quality can be improved significantly by linking thermal profiling and intelligent compaction, said Kowalski.

Intelligent compaction and thermal profiling are improving technologies that have their best days ahead of them, a compaction expert told a gathering at CONEXPO-CON/AGG 2020 on Tuesday.

“The real gains can be made when we tie intelligent compaction and thermal profiling together,” said Tim Kowalski, application support manager for Hamm, a division of Wirtgen America. “Then the paver can see what the roller is doing, and the roller can see what the paver is doing.”

Leading the presentation entitled, ‘Using New Technology in Asphalt Paving’, Kowalski said one key aspect of thermal profiling is analysing temperatures and exploring how they impact paving quality. “To improve quality, we needed to understand segregation,” Kowalski said.

While intelligent compaction (IC) has many definitions, it ultimately involves using technology and data to improve compaction and quality.

The profiling efforts began in earnest in about 2009, with the use of thermal imaging cameras. “It gave us some great data,” Kowalski said.

That data leaped forward about five years later when scanners replaced cameras. “Scanners are more accurate and not as cumbersome,” which translates into more widespread use, Kowalski said.

Thermal profiling today can incorporate the temperature of the road before paving, the speed and direction of wind, humidity and other factors.

Both profiling and IC technologies have grown, and they can be merged to provide a complete picture – from the temperature of the mix that arrives, to cooling windows, to the mat left behind the paver and eventually the compaction processes that follow.

If the technologies are coordinated, rollers can anticipate issues and adjust. IC also ensures the rolling can be recalibrated as needed. It enables tracking procedures as well.

Equally important, is off-site data analysis to track what paving and compaction processes, including rolling patterns, worked best. So reliable is this data that some states are removing specifications as long as IC is properly implemented.

The use of IC and thermal profiling continues to grow. In 2004, three states were utilising one of the technologies, compared to 33 states in 2019. In 2020, more than 800 state transportation projects across the U.S. are expected to use IC and/or thermal profiling.

Kowalski predicts that IC will soon be standard operating procedure – and standard on compactors, too. “It’s like when cars first got air conditioning,” he said. Initially it was an expensive option, but as time went on it became an expectation. “That’s where we’re heading with IC systems on rollers,” he said.

Stand S5419