This summer, U of M researchers are bringing bridge girders into their lab to help MnDOT evaluate a repair method that could ultimately reduce traffic interruptions caused by infrastructure repairs.
The salting of bridge and roadway surfaces during Minnesota winters can create highly corrosive conditions that result in damage to bridges. Such was the case with the Trunk Highway 169 Nine Mile Creek Bridge near Edina and Minnetonka, where leaking expansion joints caused corrosion to elements responsible for the strength of bridge girders: shear reinforcement, prestressing strands, and the surrounding concrete. MnDOT repaired the damaged girder ends in 2013 by encasing them using a system of steel dowels, additional shear reinforcement, and sprayed concrete. MnDOT was able to make the repairs without traffic interruption.
Now, the bridge is being replaced, and U of M professor Carol Shield and her team of researchers are evaluating the effectiveness of the 2013 repair. The researchers’ goal is to determine if the repair strengthened the corrosion-damaged girders to a level similar to noncorroded girders. If proven effective, MnDOT could use this type of repair to lengthen the useful life of existing bridges and save travelers time and frustration caused by repair-related traffic delays.
Do you work for a local transportation agency in Minnesota? Do you or your maintenance staff need funding to develop a new idea, tool, material, or process related to operations, construction, or maintenance?
The Local Operational Research Assistance (OPERA) Program is here to help! Funding for OPERA projects is now available, and it’s easy to submit a proposal. The maximum funding per project is $20,000, and submissions are due Friday, May 12, 2017.
Transportation funding continues to be a contentious issue in Minnesota: Are we spending enough, too little, too much? One way to help answer that question is to compare spending with other states.
“A simple comparison, however, may not accurately reflect the real level of transportation funding across the states,” says Jerry Zhao, an associate professor in the Humphrey School of Public Affairs. “States face different levels of demand and costs due to different geographic, demographic, or labor market conditions.”
To better understand the factors that influence the transportation funding level, Zhao and Professor Wen Wang at Rutgers University developed a cost-adjusted approach to systematically compare highway expenses among states. They found that while Minnesota spends more than average on highways, its spending level actually ranks low in cost-adjusted measures.
Have you or one of your co-workers recently built an innovative gadget or developed an improved way to do a job? Show off your creativity and help other transportation agencies solve problems by submitting an entry to the Build a Better Mousetrap Competition!
The Minnesota Local Technical Assistance Program (LTAP), housed at CTS, is participating in the 2017 contest, sponsored by the Federal Highway Administration’s Local Technical Assistance Program and Tribal Technical Assistance Program.
U of M researchers have received funding from MnDOT’s Transportation Research Innovation Group and the Minnesota Local Road Research Board (LRRB) for 15 new projects beginning this summer.
Researchers will tackle a number of big transportation questions: How should our transportation agencies prepare for connected vehicle technology? Are unseen factors affecting safety at rural intersections? Can Twin Cities roadsides be used to grow habitat for endangered bumble bees?
Posted in Bridges and structures
, Intelligent Transportation Systems (ITS)
, Traffic operations
, Transportation research
, Urban transportation
In Minnesota, the combination of traffic and extreme weather can turn small pavement problems into big potholes. To make progress in the seemingly unending task of pothole repair, U of M researchers are designing durable patches and repairs that are quick to apply and less costly for maintenance budgets.
In a new report, researchers present two improved options for pothole repair that are ideally suited to Minnesota’s cold and wet conditions. The first approach is a fast-setting, taconite-based compound, which was found to be especially well-suited for rigid and relatively deep repairs in concrete pavements. The second approach uses a vehicle-based microwave heating system with taconite materials for in-place pothole and pavement repair; this technology proved very effective for repairing potholes in asphalt pavement at all temperatures, including very cold temperatures.
Southwest Minnesota has the highest average wind speeds in the state—bad news for MnDOT snowplow operators who often drive in low-visibility conditions to clear roads.
That’s why District 7 is piloting a snowplow driver-assist system (DAS) developed by U of M researchers to combat the blowing snow and fog that often cause zero visibility. The DAS helps snowplow operators see road alignments and features such as turn lanes, guardrails, and road markings.
The DAS was developed and refined over the past 20 years under multiple research projects funded by MnDOT and the USDOT’s University Transportation Center program. Professor Max Donath, director of the U’s Roadway Safety Institute, led the work.