By Mary Lou Jay
Montana DOT used to spend hours estimating the volume of its materials stockpiles – giant heaps of salt, stone or gravel – using low-tech labor-intensive methods with a high risk of inaccuracy.
But in 2016, the agency found a better way. It introduced a high-tech process known as Digital Stockpile Management (DSM), which assists and automates the process using drones, laser scanning and other cutting-edge technology. Now, according to AASHTO’s Innovation Initiative [PDF], the process can be completed in minutes.
Employed at a wide scale, innovations like DSM promise critical savings and efficiencies. But innovation in the U.S. transportation system can be challenged by structural issues, one of the biggest being every state’s transportation agency operates independently. So, when one state DOT innovates around processes, equipment, materials or worker safety, it can be years before other DOTs learn about the time or money savings other agencies are reaping, much less get the processes in place to take advantage of it.
That’s where AASHTO’s Innovation Initiative (AII) comes in. Designed to speed up the technology sharing and implementation process among state DOTs, AII started in the late 1990s as an outgrowth of the State Highway Research Program (SHRP), focused primarily on providing information about materials improvements.
“Over time, it has broadened out to cover a wide range of potential products, processes and solutions,” said Jim McDonnell, P.E., AASHTO’s director of engineering.
Each year, state DOTs submit an application to AII with information about a successfully implemented innovation. Their idea must fall within one of six categories: construction, design, environmental, maintenance, safety and traffic.
“This is not intended to be something in the research phase, that somebody wants to test out to see if it works. It has to be something that has been tried and tested by at least one transportation agency and that has shown benefits. The idea is to share the good ideas and practices that they have with a broader audience so that everybody can gain from it,” McDonnell explained.
From these applications (usually around 20 to 30), AII currently selects five to seven Focus Technologies, which receive support to promote their idea. Over the course of two or three years, AII’s marketing and technical experts support the lead team (usually the DOT that submitted the proposal) and help plan the promotional strategy. That includes developing a website, technical briefs, sponsoring a webinar, and potentially arranging a peer exchange presentation.
Funding for AII comes from voluntary contributions from state DOTs, although states do not have to contribute in order to apply to the program. “AASHTO’s business model is sharing information among the membership to the benefit of everyone. So this is already in their mindsets; if you have a new idea, share it with others,” McDonnell added.
AII’s website includes links to information about the Focus Technologies and former Additionally Selected Technologies it has supported through the years. One currently supported innovation is the Electrically Conductive Concrete (ECON) Heated Pavement System (HPS), which features a new type of heating element that maintains roadway and runway pavements above freezing temperatures, preventing snow and ice accumulation.
AASHTO is currently helping to promote a new cost-effective and structurally efficient alternative to conventional repair techniques for repair of corroded steel bridge beams through its focus on the innovative Beam Repair Using Ultra-High Performance Concrete. The new repair technique involves welding shear studs to the intact portions of the web plate and encasing the beam end with UHPC, creating an alternate load path for bearing forces to bypass the corroded portion of the beam.
“One of the things that we got on board with very early and started promoting that seems to be taking off now is e-construction, which includes anything in the construction realm that goes digital,” said McDonnell. “We started getting the information out there in 2014 and showing how it benefitted the states. That was a big change for a lot of agencies, so it took a while to catch on. Now every state is pushing towards that goal.”
The selected e-construction AII Focus Technology in 2014 was the Michigan DOT’s digital document management system. It enabled MDOT to store electronic signatures and project-related documents in one location that could be accessed by dozens of users/agencies in seconds. AASHTO assisted the lead team for this technology with the creation of a brochure, fact sheet, and FHWA webinar that explained how MDOT had implemented this technology and benefited from it.
“Another benefit of this program is that when technologies start getting promoted widely companies start saying, ‘Hey, there’s a market for this, maybe we’ll develop something similar, or something even better,’” McDonnell said.
Autonomous option for work zone protection
AII’s promotion efforts may also encourage private sector companies to adopt new technology. Tyler Weldon, P.E., state maintenance engineer at the Colorado Department of Transportation, is hoping highway contractors will consider the Autonomous Truck Mounted Attenuator (ATMA), which AII chose as an Additionally Selected Technology in 2021.
The truck-mounted attenuators (TMA) used in work zones absorb the impact when an errant car or truck hits them (instead of a worker or the work zone). But the driver of the impact crash truck may suffer serious injuries from that impact. To reduce that risk, CDOT began exploring the use of a driverless TMA in 2017.
The autonomous technology came from the military, which employs driverless vehicles on artillery ranges. Royal Truck and Equipment adapted the system for the attenuator trucks, and CDOT was one of its first customers.
CDOT’s ATMA trails a driver-operated, paint-striping lead vehicle. It follows or replicates the leader truck’s driving maneuvers, maintaining a specified gap distance between the two vehicles. The gap can be anywhere from 25 to 1,500 feet.
After running system validation tests in the summer of 2017, CDOT introduced its new ATMA through a Facebook Live event, successfully demonstrating how it worked while striping a pavement in Fort Collins, Colorado. The Department has since added another ATMA, and each truck has now been employed on about 150 operational miles of road striping.
In 2018, CDOT and other states started a pooled fund, a Federal Highway Administration program that enables states to collectively work on research and implementation efforts. Today Missouri, California and Minnesota have ATMAs and several other states are in the process of exploring and purchasing them.
AII helped spread the word about the technology by assisting CDOT in setting up an ATMA internet page. Weldon realizes, however, that adoption is a long-term process, especially due to state DOTs’ budgetary and fleet program turnover.
That’s why he likes to get the private industry interested in using it. “The big players in striping haven’t looked at this, because it’s not cost effective yet. But just one accident would pay for the technology,” Weldon said. “Once that technology stabilizes, and the systems get smaller and easier to install, that’s when it should really take off.”
Through AASHTO’s Innovation Initiative, state transportation agencies and the companies that work with them are learning about new technologies like the ATMA faster than ever before. Using this knowledge and implementing these new tools enables both the public and private sector to be more effective and more efficient in carrying out their own transportation projects.