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. 

A construction specification is just like a recipe: It spells out the types and quantities of ingredients and the steps that should be followed to make a great product every time.   

Asphalt pavements are made by measuring and combining a precise formulation of aggregates, binder, and additives to suit the road’s anticipated traffic volume and other considerations. This mixture is then placed on the roadway and methodically compacted with heavy equipment to smooth the surface and squeeze out the right amount of air.  

In 2016, an Iowa DOT research project investigating the necessary amount of compaction led to several changes to Iowa’s asphalt pavement specifications. The next phase of that project, which concluded in 2021, sought to verify that the updated specifications do indeed result in better-performing pavements. Evaluating three types of asphalt specimens that were made using the old specifications and comparing them with samples made with the new specifications, researchers found that the new specimens were more resistant to rutting, fatigue cracking, and low-temperature cracking. 

When built with the new specifications, Iowa’s roads will likely need less maintenance and repair – a win for taxpayers and all road users alike. 

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

From the time of construction, concrete bridge decks are exposed to a wide range of mechanical and environmental stressors. Adding fibers and modifying the concrete mixes used for bridge decks can transform their strength and durability, while minimizing the need for maintenance and repair over time.  

To enhance the performance and longevity of bridge decks, researchers investigated the use of fibers and other additives to improve the conventional concrete mixes and mitigate cracking issues. This project involved testing a number of concrete mixes, varying the types and amounts of fibers and other ingredients to identify the combinations that produce a stronger, more durable, and yet workable concrete.  

Bridge engineers across the state can use the newly developed fiber-reinforced concrete mixes as a cost-effective solution to minimize bridge repair and reconstruction needs and give Iowa’s drivers a better travel experience with fewer disruptions.  

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

Iowa DOT’s engineers have long recognized the link between the quality of a pavement’s foundation and the long-term durability of the finished road. But despite improvements in how foundations are designed and the types of materials that are used, there is sometimes still a gap between how the road is intended to be constructed and what is actually built.  

Advancements in technology now make it possible to directly measure and analyze a pavement’s foundation during the construction process to ensure it has been compacted sufficiently and uniformly. This gives inspectors the tools to pinpoint any weaknesses in real-time so they can be addressed while construction is still underway.  

With a grant from the federal Accelerated Innovation Deployment (AID) Demonstration program, Iowa DOT and a team of engineers recently piloted new tools and methods to assess the foundations at five road construction projects across the state. The efforts helped the team better understand what measurements should be taken, how the equipment should be used and calibrated, and how the data should be interpreted.  

The project’s results will help Iowa DOT and other transportation agencies across the country save significant resources as better foundations lead to longer-lasting pavements with fewer maintenance needs.  

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

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.

The federal Every Day Counts (EDC) program provides tools and resources to help states put proven transportation-related technologies and innovations into practice.

Every two years, the EDC program unveils a new innovations cycle, including timely transportation topics and strategies for implementing the innovations locally.  

Since the program began 12 years ago, Iowa DOT Research has worked closely with EDC to leverage the available resources to solve dozens of transportation challenges across the state. Some of the EDC contributions to Iowa include:

• Faster emergency response times. Iowa DOT’s Mobile Architecture for Communications Handling software offers an array of maps and communications tools to help local law enforcement, agencies and emergency responders coordinate in real time.
• Streamlined construction processes. Thanks to EDC, Iowa DOT became the first state transportation agency in the country to require digital signatures on all construction contracts. And all of Iowa DOT’s construction projects have been 100% paperless since 2016.
• A diversified workforce. Iowa DOT has used EDC strategies to improve its recruitment, training and placement services so that women, minority groups and other non-traditional construction workers have the skills needed for long-term careers in transportation.

The EDC recently announced its seventh round of innovation topics, and Iowa DOT Research will collaborate with Iowa transportation stakeholders to attend a virtual kickoff event next month. The event will highlight the new resources available and how they can benefit Iowans across the state.

From now until March 15, Iowa’s Statewide Transportation Innovation Council (STIC) will be collecting ideas for innovations and technologies eligible for STIC Incentive Funds. Unlike other types of funds that aim to advance research, STIC incentive funds must be used to accelerate the adoption of innovative techniques and technologies.  

Each federal fiscal year, Iowa may apply for up to $100,000 in STIC funding, and the Iowa DOT provides an additional $25,000 that is required as a state-funded match. Examples of projects that may be eligible for these funds include guidance and specification development, peer exchanges to help states share their knowledge, and other activities that help innovations become standard practice. For more information on eligible ideas, please visit the current campaign website.  

The Iowa Highway Research Board, which serves as Iowa’s STIC, will rank the STIC submissions in April. Selected ideas will then be submitted to FHWA for funding consideration.

For additional information, please visit FHWA's STIC Incentive Program Guidelines. 

2022 was a banner year for the Iowa Highway Research Board (IHRB)! 

The IHRB aims to help Iowans at the local level by bringing together stakeholders from public transportation agencies, academia, and the private sector to identify and support high-value transportation projects.  

With funds contributed by the Iowa DOT and Iowa’s cities and counties, the IHRB managed more than a hundred transportation research initiatives in various stages of development in 2022. These projects seek to save taxpayer dollars by improving roads, increase mobility by predicting where future floods will affect the state’s highways, and enhance sustainability by exploring carbon-reducing alternative materials and methods.  

Learn more about the IHRB and its accomplishments last year.

The new Spring Research Cycle opened on March 1, bringing a new chance to see your research ideas become reality.   
 
Yours may be the next great transportation-related idea; submit it now and give it the best chance to grow into a fully developed project!   
  
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 toward helping it succeed.  
  
With more feedback and engagement, ideas become better, making them more likely 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 the spring cycle will remain open until July 25, 2023.   

You can head to the Ideas site now to review, rate, and comment ideas that were submitted in the fall. 
 
You can also visit our website to learn how the whole process works throughout the year -- Check it out and see what ideas are growing at Iowa DOT Research! 

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. 

Iowa DOT is part of a National Cooperative Highway Research Program (NCHRP) project identifying high-impact communications strategies for research conducted by Midwestern state DOTs.  

Iowa’s project Holding Strategies for Low Volume State Routes rose up as one example of valuable research with potential for wide dissemination and tech transfer. 

The two-phase Iowa DOT research project evaluated the effectiveness and costs of a variety of pavement preservation techniques, giving Iowa’s engineers better decision-making power when it comes to making the state’s asphalt roads last longer with available funds. 

To help spread the word about these research findings and impacts, the NCHRP effort included the creation of a short video featuring Iowa’s research project. You can view it on the Iowa DOT Research YouTube channel. 

Learn more about NCHRP Project 20-44(28), and check out what else Iowa DOT is working on at the Ideas site. 

Iowa DOT already leads the nation in working with 3-D virtual models to design the state’s bridges. Now the agency is taking the technology another step further.  

Because modifications often occur during construction, the model that was used to design the bridge can be outdated by the time it’s completed. On site revisions and updated specifications are hand-drawn on paper, which can be difficult and time-consuming to collect and integrate with the original digital design. This can pose an issue when it comes time to manage the bridge, as inspectors and maintenance workers may have a digital blueprint that doesn’t match the real structure.    

In a pilot project, Iowa DOT pushed the limitations of the proprietary design software it uses. Working with agency engineers and construction contractors, Iowa DOT incorporated changes from a recently completed bridge, updating the original design with the alterations made during construction. Links to supplementary information, such as photos and materials certifications, provide a holistic record of the completed bridge.  

With a better understanding of how the software needs to improve to keep up with modern needs, Iowa DOT is closer to achieving its goals for a fully digital design, construction, and asset-management process. 

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

Like other states, Iowa has traditionally taxed fuel purchases at the pump to help finance the necessary maintenance and construction work on the state’s roads and bridges. But as people drive less and vehicles become more fuel-efficient, Iowa needs to find other sources of funding to keep pace with rising costs.  

To review the solutions used by other states and determine the most equitable course of action, Iowa DOT launched a research project that evaluated a number of potential revenue sources and the financial, administrative, and political viability of each. 

The results offer promising ideas for generating revenue through alternative means as well as practical strategies for adopting them. The information will help the agency engage with stakeholders and elected officials and choose the best methods to ensure Iowa’s roads and bridges are properly funded for years to come. 

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

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 (HVR) award.   

As a member of Region 3, Iowa competes with eight other Midwestern states – Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Ohio, and Wisconsin. After winning 12 HVR awards, (including supplemental HVR awards) in the last 10 years, Iowa is looking to do it again in 2023.  
 
The projects Iowa has submitted for consideration this year are: 

• Roadway Friction Modeling: Improving the Use of Friction Measurements in State DOTs. Pavement friction helps vehicles maintain control on a roadway. Like other states, Iowa DOT uses friction measurements to determine where salt or other treatments should be applied to improve surface conditions. In this project, collected data was used to train and improve computer models so that friction can be accurately predicted even when measurements aren’t available.     

• Assessment, Repair, and Replacement of Bridges Subjected to Fire. Though bridge fires don’t happen often, they can be destructive and costly. This research provides tools and guidance that will help the state’s engineers evaluate damage and make decisions in the aftermath of a fire.    

• Development of Non-Proprietary Ultra-High-Performance Concrete (UHPC) for Iowa Bridges. UHPC is stronger and more durable than regular concrete, but proprietary formulas make it cost-prohibitive for many applications. This project developed non-proprietary UHPC mixtures that can be made with materials readily available in Iowa for a fraction of the typical cost.  

• Development of Digital As-Built: Incorporating As-Built Information into the I-80/I-380 Building Information Model (BIM) for Use in Future Asset Management Applications. Because modifications often occur during construction, the model that was used to design a bridge can be outdated by the time the bridge is completed. In a pilot project, Iowa DOT incorporated changes from a recently completed bridge, updating the original design with the alterations made during construction. With a better understanding of how the software needs to improve to keep up with modern needs, Iowa DOT is closer to achieving its goals for a fully digital design, construction, and asset-management process.  

After reviewing all of the projects submitted by the Region 3 states, AASHTO’s Research Advisory Committee will recognize the winners at the committee’s summer meeting in July. The winning states 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. 

Learn more about the HVR Awards Iowa has won over the years. 

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.

Iowa DOT Research’s innovative use of crowdsourced data to detect and respond to highway incidents was recognized in the May/June 2023 issue of Innovator, the Federal Highway Administration’s bimonthly newsletter. 
 
Through partnerships with high-tech companies like Waze, Iowa DOT is able to access to travel-related data that can indicate real-time changes in estimated travel times. While members of the public often use the free navigational app to avoid slow-downs, Iowa DOT can use the data to identify where crashes, heavy traffic and adverse weather are occurring and respond quickly. Thanks to this partnership, emergency response times have increased to save lives and make travel safer for everyone.  
 
Learn more about how Iowa DOT’s partnership with Waze can benefit all road users.  

Do you have the next big idea in transportation research? Share it now to be considered before Iowa DOT’s Spring Research Cycle ends June 30th. 

Even if you don’t have a submission of your own, you can help others improve their ideas by voting or adding your comments.

Currently, ideas that were submitted in the Spring will be open for feedback until July 25, 2023. You can review, rate and comment on ideas in Open Feedback right now!

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!

Each year, Operation Safe Driver Week reminds us of the importance of safe driving practices.

Taking place this week, from July 9-15, the annual event aims to reduce crashes and save lives.

Road safety is a cause that’s near and dear to Iowa DOT Research. Through the Partnership for the Transformation of Traffic Safety Culture pooled fund, we’ve combined resources with 13 other similarly motivated state transportation agencies to find, fund and implement innovative strategies that increase safety for all road users.

By working together, the pooled fund has accomplished way more than an individual agency could on its own limited budget. From investigating the effects of cannabis use on driver behavior to identifying ways to reduce drivers’ cell phone use, the pooled fund has advanced the state of knowledge on dozens of road safety topics.

Learn more about Iowa DOT’s involvement with pooled funds and how it helps the agency make the most of every research investment. </p>

What does a year of transportation research look like? The Iowa DOT Research Section is proud to showcase its efforts in the new FY2022 Research At-A-Glance report.

With more than 200 research projects initiated, progressed or completed throughout the year, Iowa DOT gained valuable information on a variety of cutting-edge topics. From finding new uses for waste quarry fines ways to increasing the value of 3D Building Information Models, Iowa DOT Research continued to prioritize safety, mobility, sustainability, and technology to make transportation better for Iowans across the state.

The At-A-Glance also outlines the process Iowa DOT Research uses to gather research ideas, develop the research program, and work with partners to accomplish research objectives.

Interested in learning more about what Iowa DOT Research did in 2022, how it was done, and what’s coming next? Check out the full report!