Katie Johnson

The green spaces along sloped urban highway roadsides can present a variety of challenges for maintenance crews. Mowing these steep areas can be hazardous, but pollution and other factors can make it difficult to grow anything other than turfgrass.

To find low-maintenance alternatives, the Michigan Department of Transportation (MDOT) commissioned a research study to test and track a variety of soil improvement strategies and plant types over several years. The efforts resulted in a documented process for improving roadside soils as well as a list of plants that can be reliably grown—and which require minimal maintenance—along sloped areas in similar climates.

View the video and read the two-page brief to learn more about the project’s findings.

Image source: Michigan Department of Transportation

The Washington State Department of Transportation will host the virtual webinar, “Forensic Evaluations: Listen to What Our Pavements are Telling Us” on Wednesday, April 20 from 12:30 – 1:30 p.m. Central.

Through the federal Long-Term Pavement Performance (LTTP) program, data collected on pavement sections removed from service have helped explain how and why the pavements performed as they did. This webinar will discuss the history of the LTTP program, its evolution to become a current pooled fund study and what insights the data have provided.

Learn more and register.

Image source: Washington State DOT

Blisters, or bulges of an asphalt pavement’s surface, sometimes occur when moisture becomes trapped between layers of asphalt. However, a variety of environmental, material and other factors contribute to whether blisters appear and how severely they form, making them a challenge to predict and study.

To better understand why blisters occur and how they affect the pavement’s service life and ongoing maintenance needs, the Florida Department of Transportation compared five segments of the same road project with and without blisters. The research resulted in recommended paving strategies to keep these distresses from forming, as well as guidance for repairing blistered pavements.

Read the research summary: Evaluation of Roadway Worms/Distortions, February 2022.

Image source: Florida Department of Transportation

To identify which pavement marking materials work best on asphalt surfaces in the Midwest, the Joint Transportation Research Program—a collaboration between Indiana DOT and Purdue University—developed and assessed a variety of new testing methods and protocols.

Designed to assess a range of properties, such as elasticity, durability and bond to the pavement, the tests can help maintenance crews identify tapes and thermoplastics that are likely to adhere well to pavements and withstand extreme temperature fluctuations.

Read the report: Mechanical Properties of Durable Pavement Marking Materials and Adhesion on Asphalt Surfaces, October 2021

Image source: Joint Transportation Research Program

Earlier this month, California Department of Transportation’s Division of Research, Innovation and System Information (DRISI) presented an hour-long webinar on two recently initiated research studies related to highway maintenance.

The webinar featured presentations from both projects’ researchers, who discussed the goals and anticipated outcomes of their work.

First, Dr. Bahram Ravani from the University of California, Davis described how his team is developing a new maintenance prioritization tool, using project location, activity type and other considerations to determine risk. The tool is intended to improve highway workers’ safety while increasing the efficiency of maintenance work.

Next, Dr. Simon Bisrat, who manages the DRISI Environmental Impact Mitigation Research Program, described the cost-effective mitigation strategies that can be integrated with existing highway infrastructure to allow sensitive wildlife like amphibians and reptiles to cross safely.

Learn more about both projects by watching the recording on YouTube: Mitigating Safety Risks and Environmental Impacts, March 2022.

Image source: DRISI

The March/April 2022 issue of Innovator, the Federal Highway Administration’s bimonthly newsletter, showcased a number of exciting innovations from No Boundaries member states.

Connecticut and New York State DOTs were highlighted for their work to advance the use of ultra-high performance concrete for bridge repairs. Texas DOT won a 2021 National Roadway Safety Award for its Safety Scoring Tool, which uses predictive technology to show the outcomes of a project’s design before ground is even broken. And Colorado, Missouri and Texas DOTs were recognized for their use of State Transportation Innovation Council funds for a wide array of time- and cost-saving initiatives.

Sign up to get the next issue of Innovator delivered to your inbox.

Image source: FHWA