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.
CTS scholar Cathy French and three U of M students were honored by WTS Minnesota at the organization’s 2017 Scholarships and Recognitions Luncheon on April 27.
French, a CSE Distinguished Professor in the U’s Department of Civil, Environmental, and Geo- Engineering, received the 2017 Woman of the Year Award. The annual award recognizes women who are outstanding role models in transportation.
U of M students Maria Wardoku, Ella Rasp, and Claire Warren received scholarships that recognize women pursuing undergraduate and graduate degrees in transportation-related fields.
MnDOT is exploring the development of freeway “lids” at key locations on I-94 in the Twin Cities. To analyze the potential for private-sector investment and determine what steps might be needed to make lid projects a reality, MnDOT invited the Urban Land Institute (ULI) MN to conduct a Technical Assistance Panel with real estate experts and other specialists. The U’s Metropolitan Design Center (MDC) provided background and research for the panel.
A lid, also known as a cap or land bridge, is a structure built over a freeway trench to connect areas on either side. Lids may also support green space and development above the roadway and along adjacent embankments. Although lidding is not a new concept, it is gaining national attention as a way to restore communities damaged when freeways were first built in the 1960s.
According to MnDOT, roughly half of the 145 bridges on I-94 between the east side of Saint Paul and the north side of Minneapolis need work within the next 15 years. A shorter window applies in the area around the capitol to as far west as MN-280. In anticipation of the effort to rebuild so much infrastructure, the department wanted a deeper understanding of how attractive freeway lids and their surrounding areas would be to private developers and whether the investment they would attract would generate sufficient revenue to pay for them.
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
A new video showcasing our research and education highlights over the last year debuted in April at our Annual Meeting and Awards Luncheon. Highlights include research on accessibility, jobs and transit, the national freight economy, and bridge monitoring as well as our transportation summer camp for middle schoolers.
Recently, unmanned aircraft systems (UAS) have been making headlines for their wide-ranging applications—from aerial photography to package delivery for major retailers—and for their accompanying regulatory, safety, and privacy concerns.
In an October 15 Roadway Safety Institute seminar, Associate Professor Demoz Gebre-Egziabher of the U of M’s aerospace engineering and mechanics department reviewed some UAS-related opportunities and challenges. He also discussed some of the UAS research being conducted at the U of M’s Uninhabited Aerial Vehicle (UAV) Laboratories.
During the past decade, a number of major weather events have disrupted or damaged transportation networks. According to staff scientist Joe Casola with the Center for Climate and Energy Solutions, in some cases trends in the frequency or intensity of these events can be linked to longer-term changes in the climate, while in all cases the events demonstrate the vulnerabilities associated with our transportation infrastructure and services.
During the luncheon presentation of the annual CTS research conference, Casola outlined some of the climate trends that will continue to affect our nation’s transportation systems in the coming years. “The big picture is that carbon dioxide levels are on a steady march up, and with that the average temperature of the planet is warming,” Casola said. “For decision makers on the ground, the more important issue is the increased frequency of the extreme weather events that occur over days or weeks at the local and regional levels.”