MnDOT construction projects require tons of hot mix asphalt each year, with over 188 road and bridge projects in the 2020 construction season alone.
Historically, plant mixed asphalt has been weighed, tracked and paid for with computer-generated paper tickets. Paper ticketing isn’t an ideal process for a variety of reasons—on-site ticket collection poses safety risks, tickets can be easily lost, and data must be tabulated manually, just to name a few.
Continue reading Asphalt Delivery Tracking Goes Digital with Some 2020 Construction Projects
Cities and counties need affordable pavement preservation treatments, but preservation strategies are often geared towards higher-volume roads. The Minnesota Local Road Research Board has developed new guidance on five lower-cost treatments that is more applicable to local agencies and can be used to preserve pavements based on the type and severity of pavement distress.
Continue reading Pavement Preservation Techniques for Local Agencies
Reinforced concrete bridges are built to handle heavy loads and routine traffic for 75 years or more. But bridges in climates like Minnesota’s are exposed to moisture and chlorides from road salts that may penetrate these structures and corrode the steel.
In a recently completed research project, funded by MnDOT and the Local Road Research Board, researchers studied a rural bridge built in 2017 near Elgin, MN, that used glass fiber–reinforced polymer (GFRP) rebar in the bridge deck. They found that GFRP performed well, proving sufficiently strong for use as an alternative to corrosion-susceptible steel rebar.
Continue reading GFRP Rebar Shows Promise for Use in Bridge Decks
Just in time for spring, new guidance is available from the Minnesota Local Research Board on the best irrigation methods to establish fresh turfgrass. Researchers tested five irrigation methods for watering new installations of salt-tolerant turfgrass. They developed an instructional course for contractors and guidance for homeowners to promote successful turfgrass installation.
Continue reading Improving Roadside Turfgrass Establishment
A newly developed system helps traffic engineers quickly spot failing loop detectors, which are used to monitor traffic volumes on Minnesota highways. The software program, developed by the University of Minnesota-Duluth for the Minnesota Department of Transportation, evaluates loop detector data and reports current loop detector health in an easy-to-read graphic format, making it easy to identify loop detectors in need of repair and which loop detectors should be used for the most accurate traffic counts.
Continue reading Improving Traffic Volume Estimates By Monitoring Health of Loop DetecTORS
Rural intersections account for 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly understood safety problem.
Transverse rumble strips are one low-cost measure that some states have deployed to reduce rural intersection crashes.
Continue reading Transverse Rumble Strips: Another Tool for Rural Road Safety?
The Minnesota Local Road Research Board (LRRB) has added pavement condition forecasting technology to an existing, web-based roadway inventory tool that will enable counties to generate low-cost maps and reports that help them prioritize their work by showing how roadway conditions will look under different construction scenarios for decades to come.
Continue reading Low-Cost Pavement Condition Forecasting Software Eases Local Road Planning
April 22 is Earth Day!
Climate change & the environment is one of five research strategic priorities that guide the work of the state transportation research program.
This includes research projects specific to endangered & threatened species, wetland protections, salt use and incursion, congestion impacts on air quality, and the impacts of road construction and maintenance activity on the environment.
Continue reading Earth Day 2020
Well-documented efforts undertaken two decades ago to mitigate corrosion of a Highway 394 reinforced concrete bridge have given researchers the perfect scenario for evaluating the treatments’ long-term effectiveness. The test results are mixed: State-of-the-art methods for electrochemical chloride extraction and fiber-reinforced polymer wrapping of bridge elements performed well in combination, but poorly in isolation.
Continue reading Methods to Mitigate Bridge Corrosion Show Mixed Results 20 Years Later