Though specialized geotextile fabrics have been used in the construction of concrete highways in the United States for more than a decade, their long-term influence on the pavements has not been well understood.  

With a shared interest in learning more, Iowa DOT and 34 other states jointly commissioned a research project to study three different types of geotextiles and their long-term effects on concrete pavements.   

Using sections of Iowa’s Buchanan County Highway D-16 for testing, researchers evaluated stress and deformation of the concrete and compared road sections constructed with each of the geotextile fabrics and sections built using traditional methods.   

The resulting data gives the states greater insight when it comes to deciding which projects are well-suited for using geotextiles and demonstrated the reliability of the on-site testing techniques.  

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Held every year in January, the annual meeting of the Transportation Research Board (TRB) is always a major event in the transportation research community, routinely attracting thousands of scientists, researchers, and other professionals from across the country and around the globe. 

This year’s event, like so many others recently, will be held virtually. And while the business meetings and technical programs that comprise TRB’s 2021 Annual Meeting may be conducted a bit differently as a result, the ability to attend without traveling and incurring related expenses will mean an increase in the number of participating agencies and volume of shared expertise. 

Iowa DOT is a frequent participant and presenter at TRB’s annual meetings, contributing to the event’s valuable information exchange. Thirty-seven Iowa DOT staff members currently serve on 75 TRB committees, meaning Iowa holds a pivotal role in the national transportation scene. 

This year will be no exception, as Iowa DOT staff will lead presentations on innovative bridge design and construction projects and winter maintenance technologies, in addition to participating in several panels discussions and conducting committee work.

Involvement in transportation research at the national level helps Iowa stay abreast of cutting-edge developments and ensures our state has a voice in national transportation discussions.  

Iowa DOT staff who don’t typically attend the TRB Annual Meeting are encouraged to take advantage of this year’s unique online format. There is no charge for Iowa DOT employees to attend the TRB annual meeting, which runs throughout January, but advanced registration is required. 

Learn more about how Iowa will contribute to the 2021 TRB meeting later this month and how Iowa works with TRB.

Each year, the American Association of State Highway and Transportation Officials (AASHTO) honors the best transportation research projects from each of its four regions with a prestigious High Value Research award.  

As members of Region 3, Iowa and eight other states – Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Ohio, and Wisconsin – will face off for 2022 awards. The projects Iowa has submitted for consideration this year are:
 

• Self-Heating Electrically Conductive Concrete Demonstration Project (E-Con). This project represents the largest-to-date field study of electrically conductive heated concrete, using electrodes embedded in the concrete to melt snow and ice on the surface. The results could one day be used to target ice-prone areas like bridge decks without repeated salting.

• Bio-Based Polymers for Use in Asphalt - Phase II. In phase I of this study, researchers developed renewable materials from vegetable and soybean oil that can replace the dangerous binding material traditionally used in asphalt paving mixtures. In phase II, researchers built a pilot facility capable of producing enough biopolymers to support field demonstration projects that showcase the materials’ performance and cost-effectiveness.

• Economic Impacts of Atmospheric Rivers in the Transportation Sector: Methodology and Case Studies. As lead state of the Aurora Pooled Fund, Iowa and other state DOTs worked together to learn more about atmospheric rivers, their role in producing extreme weather and effects on transportation systems.

• Investigation of Autonomous/Connected Vehicles in Work Zones. This research, produced by the Iowa-led Smart Work Zone Deployment Initiative (SWZDI), used simulations to explore how driverless vehicles programmed to follow a lead vehicle could interact with surrounding traffic around work zones, where speed reductions and lane changes are common.

 
After reviewing all of the Region 3 submissions, AASHTO’s Research Advisory Committee will choose the winning projects to be recognized at the committee’s summer meeting in July. Winners will also participate in a poster session dedicated to high-value research projects at the annual meeting of the Transportation Research Board in Washington, DC in January 2023.

July was a busy month for Iowa to share the advancements it’s made in transportation research with peers from other states and around the world! 

From July 23-26, the Iowa Highway Research Board and Iowa County Engineer’s Association hosted the 13th International Conference on Low Volume Roads. 

The event only happens every four years, and this year’s conference in Cedar Rapids brought hundreds of attendees from more than 20 countries to exchange strategies and new technologies to address the challenges of planning, designing, constructing, operating and maintaining unpaved roads.  

It also offered an exciting opportunity for Iowa to demonstrate its innovations and state-of-the-art practices during a half-day tour of low-volume roads and the Sutliff Bridge in Johnson County.  

During that same week, from July 23-28, representatives from Iowa DOT Research and peers from other state transportation research programs gathered in Chattanooga, Tennessee for the American Association of State Highway and Transportation Officials (AASHTO) Research Advisory Committee (RAC) annual meeting.  

This national event offers a forum for states to discuss cutting-edge ideas and innovations in transportation research. The AASHTO RAC meeting is also where states’ research efforts are recognized and honored; Iowa DOT shared details of its project to train and improve computer models to predict where deicers should applied during winter storms, which was selected for one of AASHTO’s prestigious 2023 Supplemental High Value Research Award.   

This award marks the 13th HVR award (including supplemental HVR awards) that Iowa DOT Research has earned in the last 10 years.     

It’s an exciting time at Iowa DOT Research as we gear up for the fall research cycle, beginning November 1!

If you have a great transportation-related idea, early in the new cycle is always the best time to submit for maximum exposure. 

Submitting an idea at the start of the new research cycle means it will have the most time in the discussion and evaluation phase – a critical step for helping it succeed.

The more feedback and engagement an idea receives, the better chance it has to be selected for further development. 

Even if you don’t have a submission of your own, you can help others improve their ideas by voting or adding your comments. Feedback for this fall cycle will remain open until March 25, 2021. With three research cycles throughout the year, ideas are always in progress at Iowa DOT research.

Check out the annual research calendar to see the process, and mark your calendar for November 1 to see what’s new or submit your own idea! 

To keep local roadways in good condition for the traveling public, Iowa county engineers monitor pavement conditions and analyze a wealth of pavement data to predict when and where maintenance will be needed. Now, a new tool developed through a research project for the Iowa Highway Research Board will help streamline this complex process.  

Developed through extensive analysis of past pavement performance data from Iowa roadways, the Iowa Pavement Analysis Techniques (IPAT) tool will help engineers accurately and efficiently estimate the remaining service life (RSL) of individual pavement sections or roadway networks. Armed with reliable RSL estimates, engineers can plan and prioritize maintenance treatments and rehabilitation projects to make the best use of limited county funds. The IPAT tool will be implemented across the state in the coming months. 

Learn more about this project in Iowa DOT’s new research brief and final report. 

Each year, the American Association of State Highway and Transportation Officials (AASHTO) honors the best transportation research projects with High Value Research (HVR) awards. Supplemental HVR Awards are also given for research conducted on topics of special interest. 

This year, Iowa’s efforts to train and improve computer models to predict where salt or other treatments should be applied during winter weather to make roads safer was selected for the supplemental award by the agency’s eight peers in AASHTO Region 3: Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Ohio, and Wisconsin.

Like other states, Iowa uses a mix of stationary and mobile sensors along the state’s highways to measure road friction and guide its winter maintenance activities. This research used friction models to accurately estimate where treatments are needed even in locations of the state where sensors aren’t available.  
  
This award marks the 13th HVR award (including supplemental HVR awards) that Iowa DOT Research has earned in the last 10 years.    
  
AASHTO’s Research Advisory Committee will recognize all 2023 winners during its summer meeting in July. Winners will also participate in a poster session dedicated to high-value research projects at the annual meeting of the Transportation Research Board in Washington, DC in January 2024.

Behind every Iowa DOT research innovation is a real human being dedicated to helping ideas become reality. Here you can learn more about the Iowa DOT Research staff members and what makes them tick. 

Name: Vanessa Goetz, State Research Program Manager – Iowa Highway Research Board
Number of years in this role: 9 

What do you do in the Research & Analytics Bureau? 

I manage Iowa's state-funded research programs. I also serve as the executive secretary to the Iowa Highway Research Board, which has a long history of delivering solutions to Iowa’s transportation research needs.

In addition, I am the point of contact for the bureau for the Federal Highway Administration’s innovation programs, including the State Transportation Innovation Council, Accelerated Innovation Development (AID) Demonstration, and Every Day Counts. 

Have you always been drawn to research? What has your career path been like? 

Yes, I have been involved in research in various ways since college.

Unlike most of my colleagues who are civil engineers, I’m actually an industrial engineer.

Among my jobs before I came to Iowa DOT was working in a private R&D lab researching cat litter.

Another job was assisting research on improvements for K-12 curriculums through the College of Education at Iowa State University.

I started with Iowa DOT in 2003, in what was then the Office of Materials, working with manufacturers of epoxy-coated reinforcements.

When I moved to research, I became the secondary road research engineer and served as the liaison between Iowa’s 99 counties and the research program. I was later promoted to my current position. 

What’s your favorite part of your work? 

The best part is that it’s never the same—no two projects are ever alike.

There are always new challenges that need innovative solutions to meet the needs of Iowa’s transportation and the public. 

What initiative on the horizon do you think will make a big impact for the research bureau? 

Our new website, ideas.iowadot.gov. It will bring more transparency to our program since people will be better able to see where new ideas are in our development timeline.

It will also serve as a new communication tool to help us work better with our stakeholders and partners.

Now, instead of needing multiple spreadsheets and platforms to track a project, the entire process—from idea to active and closed project—will be housed in one place. 

What do you like to do in your time off? 

I like to go camping, travel and spend time with family.

I also really like personal construction projects—it seems we’re remodeling, rebuilding or tinkering with something on our property, and usually doing the work ourselves.

With the opening of the fall research cycle on November 1 comes a new opportunity to submit your transportation-related ideas! 
 
Early in the new cycle is always the best time to submit for maximum exposure -- it allows more time for discussion and evaluation and a better chance for further development.  
 
Even if you don’t have a submission of your own, you can help others improve their ideas by voting or adding your comments. Feedback for this fall cycle will remain open until March 25, 2022. With three research cycles throughout the year, ideas are always in progress at Iowa DOT research. 
 
Check out the annual research calendar to see the year-round process and check the Ideas site often to find out what new ideas have been submitted and to provide your own!

Low-volume roads are an integral part of Iowa’s transportation network. For decades, the Iowa Highway Research Board (IHRB) has advanced research to build and maintain these roads for optimal performance. 

The national Transportation Research Board (TRB) is bringing the 13th International Conference on Low Volume Roads to Cedar Rapids, to be held from July 23-26, 2023. IHRB is partnering with TRB and the Iowa County Engineer’s Association (ICEA) to support this great conference. 

This conference, which is held every four years, brings together hundreds of researchers and practitioners from more than 20 countries around the world. These experts will share and discuss new technologies and techniques related to planning, design, construction, operation, maintenance, and administration of low-volume roads. 

The agenda includes full- and mini-workshops, a site visit, lightning poster sessions, and speaker presentations. The event is typically attended by 200 to 300 practitioners and researchers from more than 20 countries.  

Early-bird registration for this conference will end on March 23.  Visit the conference website for additional details. 

Don’t forget to sign up for the “Iowa Night” event being hosted by ICEA. Visit the affiliated Offsite Events page for information on how to register. 

Routine maintenance and preservation treatments are needed to ensure a bridge lasts as long as it was designed to.  

From cleaning and filling cracks to applying a new concrete or asphalt overlay, each treatment comes with upfront material and labor costs that are relatively easy to calculate.  

Other costs, such as those related to road user safety and the environment when a route is closed or detoured during maintenance, are not as simple to measure.   

To better understand the full spectrum of costs and benefits of different treatment options, the Iowa Highway Research Board upgraded a software tool available for use by all state and local Iowa bridge engineers. The changes make the tool easier to use and produces more accurate results, ensuring that agencies can choose the treatment option that best suits their needs and the performance goals of the bridges they manage. 

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page. 

Iowa DOT Research is constantly looking for ways to keep Iowa’s transportation system on the cutting-edge of safety, mobility, sustainability, and technology.

Before a project can begin, it must follow a thorough development process. Here’s how it works and how you can help:
 

1. Submission. Research topics can be submitted by anyone (within or beyond the department) at any time through our Research Ideas website.
    
2. Discussion and Evaluation. While ideas are in the open feedback state, anyone can provide written comments or vote on a proposed topic and help make it better.
   
   This state takes place three times per year, according to the annual research calendar.
   
   After the open feedback period closes, Iowa DOT Research Department staff and other stakeholders review the topics and all of the input received to gauge interest and determine which ideas should move forward.
    
3. Development. Next, the Project Development Group, consisting of two to five team members, takes the originally submitted idea and builds it into a more robust request for proposal (RFP).
   
   The RFP is posted to the Research Request for Proposal page and anyone who has subscribed to these notifications will receive an email.
   
   After the RFP submission period has ended, the Project Development Group reviews all of the responses and chooses the one that will earn the project.
   
   The winning proposer is notified and funding for the project is requested.
    
4. Active Project. Contracts are drawn up and signed, and the research begins!

A visual timeline details the entire process.

Behind every Iowa DOT research innovation is a real human being dedicated to helping ideas become reality. Here you can learn more about the Iowa DOT Research staff members and what makes them tick.  
 
Name: Brian Moore, Secondary Road Research Engineer  
Number of years in this role: 3 

 

What do you do in the Research & Analytics Bureau?   

As the Secondary Road Research Engineer I work as the liaison between the Iowa Counties and the Iowa Highway Research Board.  I work with the Iowa Counties to develop research ideas that will help solve their everyday challenges.   

I develop these research projects for the Iowa Highway Research Board.  I work with researchers to do projects and then upon completion, take the results and assist the counties in implementing the results of the research. 
 

Have you always been drawn to research? What has your career path been like?   

I have spent my career in local county government as a County Engineer in Iowa.

I served 3 years in Ringgold and Decatur Counties and then 17 years in Wapello County before taking the Secondary Road Research Engineer position.   

As a county engineer you are always trying to do more with less to maintain your road system.  This includes trying new research ideas.  In Wapello County I heard of a new product in 2002 called Ultra High-Performance Concrete (UHPC).   

I was drawn to its potential, which led us to building the 1st highway bridge in North America using UHPC in 2005.  Now UHPC is used worldwide and I am still involved to this day on different initiatives involving UHPC. 
 

What’s your favorite part of your work?  

My favorite part of my job is being involved from the beginning on the cutting-edge of technology and ideas. Helping to shape this new idea or technology and implement it at the county level to help all the counties in Iowa solve their problems.  
 

What initiative on the horizon do you think will make a big impact for the research bureau?   

I think the new research platform will engage our stakeholders better and will assist in getting more folks involved in the research process. 
 

What do you like to do in your time off?  

A little-known fact about me: for the past 16 years I have been a women's college basketball official, working games at all levels all over the Midwest. 

Each January, thousands of scientists, researchers and other professionals from around the world attend the Transportation Research Board (TRB)’s annual meeting to learn and share cutting-edge practices and developments in transportation-related research.  
 
As an active leader and frequent participant in TRB activities, Iowa DOT will send staff members to the 2023 TRB meeting to give presentations and represent the state at the national level.   
 
This year, Iowa DOT staff will lead discussions on enterprise data life-cycle management, asset life cycles, big data for pavements, and staged bridge construction, in addition to attending a variety of panel presentations and conducting committee work. 
 
Involvement in transportation research at the national level ensures our state has a voice in national transportation discussions. Learn more about how Iowa’s long-standing partnership with TRB helps Iowans across the state.

Behind every Iowa DOT research innovation is a real human being dedicated to helping ideas become reality. Here you can learn more about the Iowa DOT Research staff members and what makes them tick. 
 

Name: Lee Bjerke, Secondary Roads Research Engineer 
Number of years in this role: 1 
 
What do you do in the Research & Analytics Bureau?   

I am the Secondary Roads Research Engineer. My role is to be the liaison between the counties in Iowa, their engineers, and the Iowa Highway Research Board (IHRB). It is my responsibility to bring the ideas for research to the IHRB, work with the academics on research that benefits the counties and then help the counties to effectively implement the research. 
 
Have you always been drawn to research? What has your career path been like?   

I have always found research interesting. I have spent 23 years as the Winneshiek County Engineer and experienced first-hand the difficulty the counties face with upkeep and improving the secondary road systems. I served on various technical advisory committees and have implemented research such as Otta Seals, using railroad flat cars for short span bridges, and Internal Curing Concrete. One of the biggest issues I saw for counties was the damage done by the large rain events experienced by Iowa in recent years. I championed the research in using roads as impoundment structures to slow rainwater and reduce the damages they can cause. 
 
What’s your favorite part of your work?   

My favorite part of this job is seeing great ideas, regardless of where they come from, become a truly effective tool for the counties to use in improving the Secondary Road System. 

What initiative on the horizon do you think will make a big impact for the research bureau?   

I see two big ones: the AASHTO bridge rating software and the On-Road Impoundment structures. Both of these will have huge advantages to the public in ensuring their ability to traverse the roadways in Iowa in the most efficient and cost-saving manner possible. 
 
What do you like to do in your time off?   

My wife and I love the water. Boating is our favorite pastime; whether it is pulling kids on tubes, putzing along on a pontoon, or sitting in a chair on a beach, time on the water is easily our number one place to be. 

Iowa DOT is committed to advancing transportation research, but it can’t do it alone

Since 2003, Iowa DOT has partnered with the University of Iowa for help in achieving its research goals.  

Specializing in a variety of transportation issues such as hydraulics, public health, virtual reality and advanced computing, connected and autonomous vehicles, and driver behavior, the University of Iowa has provided research assistance and technical support on more than 40 Iowa DOT research projects. Some of these include: 

• Development of Self-Cleaning Culverts, led by principal investigator Marian Muste. 
• Traumahawk: Improving Treatment for Crash Victims Using Photos and a Smartphone App, led by Daniel McGehee.
• Passenger Restriction Waiver Impact on Young Driver Crash Rates, led by Michelle L. Reyes.

With each collaboration, Iowa DOT gains insight into the cutting-edge innovations and strategies that can be implemented to enhance the safety and mobility of Iowa’s traveling public.  

Thanks to its relationship with the University of Iowa – as well as other university researchers, technical authorities and other industry professionals – Iowa DOT Research has earned a reputation around the world as a leader in transportation research.

County engineers are charged with maintaining thousands of bridges on Iowa’s secondary road system. In bridges built with T-shaped concrete beams, individual beams are typically connected with longitudinal joints. These joints are vulnerable to environmental and mechanical stresses, leading to frequent maintenance and repair needs. 

New materials offer promising alternatives for these longitudinal joints, not only improving the strength and durability of individual joints but also increasing the service life of the entire bridge structure. Focusing on short-span bridges, researchers developed and tested a new design with an ultra-high-performance concrete longitudinal joint and reinforcing bars made of corrosion-resistant, high-strength steel. They found significant potential for stronger and longer-lasting bridges. 

This new bridge system will likely offer significant cost savings in the long run. The next steps for Iowa bridge engineers are to explore construction considerations in the field and evaluate the performance of this innovative bridge system in real life. 

Learn more about this project in Iowa DOT’s new research brief. 

Earth Day, which takes place annually on April 22, reminds us to evaluate our collective impact on the environment and to consider the steps we can take to reduce our footprint.  

Here at Iowa DOT Research, we are constantly on the lookout for ways to protect our natural resources.

One of the things we can do is protect our watersheds. Culverts, like the one pictured here, are designed to help water flow beneath a road, railroad, or other type of structure. When a culvert is situated in an erosion-prone location, sediment can wash in and quickly build up – disrupting the flow and causing damage upstream. 

Culvert monitoring and maintenance is an important part of Iowa DOT’s work, but it’s not the only solution. 

Dedicated to keeping our waterways clean, Iowa DOT went back to basics in 2009 to reassess every aspect of traditional culverts in an effort to find room for improvement. This work, which involved testing a variety of culvert formations over several years, culminated in an all-new culvert design that restricts sediment from entering and virtually eliminates the need for cleaning. The efforts also resulted in a prestigious national award in 2016. 

To build on these achievements, Iowa DOT has partnered with three other state departments of transportation – Mississippi, New Mexico, and Utah – to address these ongoing challenges related to culverts. By sharing the costs of research, participating states can explore alternative culvert designs and other mitigation strategies for far less than each would spend on its own.  

Learn more about Iowa DOT’s other environmental efforts, including reducing erosion at construction sites and creative recycling solutions.

As a national organization representing state departments of transportation (DOTs) from all 50 states, the District of Columbia, and Puerto Rico, the American Association of State Highway and Transportation Officials (AASHTO) is the umbrella group for dozens of smaller committees that focus on a range of specific topics. For those working in transportation research, the Research Advisory Committee (RAC) serves as a network and forum for sharing ideas and addressing common challenges.

As the AASHTO RAC is organized into four smaller regional committees, Iowa DOT interacts most with other Midwestern states in RAC Region 3. But each summer, the RAC Annual Meeting provides an opportunity for all members – from every state in the country – to come together to learn from each other. 

As a frequent participant and presenter at RAC annual meetings, Iowa DOT’s efforts produce tangible benefits for the state. By exchanging tried and tested strategies with other states, Iowa is able to identify cutting-edge solutions early and put them to work sooner. And involvement in RAC saves Iowa’s taxpayers money, since Iowa DOT can gain efficiencies by coordinating its research goals with federal and other agencies’ transportation initiatives.

The event also offers a place to recognize and reward states’ research innovations. Iowa DOT will share details of its largest-to-date field study of electrically conductive heated concrete, which was selected for AASHTO’s prestigious 2022 High Value Research Award.

Learn more about Iowa’s work with RAC Region 3.

Road friction sensors are high-tech tools that can quickly indicate slippery spots on roadways. Iowa DOT uses these sensors to better understand where salt or other deicing treatments are needed most; however, not all sensors produce the same results and their high cost means they can only be placed in key areas.  

To ensure the data collected is reliable and better understand road conditions in locations without sensors, Iowa DOT and 18 other states shared the costs of testing different sensors under simulated conditions and developing a computer model that can use weather and atmospheric data to infer the level of friction on the road. 

As more data is collected over the time, Iowa DOT will eventually be able to predict road friction anywhere in the state.    

This project was recently awarded a 2023 AASHTO High Value Research Award in the Safety Focus area. Learn more about this award highlighted in a recent News item. 

Learn more about this project in Iowa DOT’s new research brief, and check out other Iowa DOT research efforts on the News & Publications page.