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Spring research seminars begin February 6

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The spring series of CTS research seminars kicks off next Thursday, February 6. This year's topics will include bridge scour monitoring technology, roundabout signing and striping, and transit-oriented jobs-housing balance.

Seminars will be held from 3 to 4 p.m. each Thursday during February (except Feb. 20) on the U of M campus in Minneapolis. You can either attend in person or watch the live webcast of each seminar.

Additional information is available on the CTS website.

Seminar schedule:

I-35W 'smart' bridge stands the tests of time

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For the past year, researchers at the University of Minnesota have studied how the I-35W St. Anthony Falls Bridge, which spans the Mississippi River near downtown Minneapolis, is aging.

The researchers are monitoring nearly 500 sensors installed during construction of the bridge for strain, load distribution, vibrations, temperature, and the overall movement of the bridge.

As the bridge ages, the concrete naturally shortens due to a process called "shrinkage." The concrete will also "creep," meaning that it will continue to deform with time due to the permanent gravity and post-tensioning loads.

The research team is in the process of refining models to better predict the behavior of the bridge over time—data they plan to use as a baseline for detecting damage or potential problems in the structure. The award-winning bridge, which opened in 2008 after nearly 11 months of construction, is designed to last 100 years.

In conjunction with predicting the long-term structural behavior of the bridge, the research team has continued to monitor the sensors for behaviors related to temperature and time. This includes expansion joint movement, strains, and the dynamic modes of vibration.

The research team also is developing a unique prototype monitoring system that provides warnings to MnDOT Metro Maintenance personnel if problems arise in the expansion joints. They focused on the expansion joints first because those joints are easiest to incorporate into maintenance and inspection routines.

Once the monitoring framework for the expansion joint movement is finalized, the prototype also may be extended to evaluate other sensor data.

Read the full article in the November issue of Catalyst.

New bridge technology featured at demo in Luverne

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GRS.jpgIt’s an unlikely spot for a fancy new bridge. But the farmers who’ve been driving a two-mile detour for the past 20 years are quite pleased. Smack in the middle of the farm fields and prairie that blanket windy Rock County just east of Luverne in the far southwestern corner of Minnesota, you can find the state’s first Geosynthetic Reinforced Soil Integrated Bridge System (GRS-IBS).

The Federal Highway Administration (FHWA) teamed up with MnDOT and Rock County to build the bridge between snowstorms this past spring as a way to introduce the technology to wary public works officials in the state and to conduct further testing. A daylong showcase event in June, which included a tour of the project site, drew around 40 participants from five states, mostly engineers. The event was the third demo nationally of GRS-IBS as part of the FHWA’s Every Day Counts initiative.

The method uses alternating layers of granular fill and sheets of geotextile reinforcement.

There are now more than 100 of these bridge systems around the country. The GRS-IBS technology uses alternating layers of compacted granular fill material and fabric sheets of geotextile reinforcement to provide support for the bridge instead of conventional supports. The simple construction method can lower costs, slash construction time, improve durability, and increase worker safety.

“We’ve always had this location on our list of projects to do, but we never had the funding to do it,” said Rock County Engineer Mark Sehr. “With the assistance of Federal Highway and the Minnesota DOT, we were able to fund this project and, therefore, we’ll get one of our roadways open that’s been closed for a number of years.”

And if everything works out as planned, there’ll be no bump between the bridge and approaching roadway caused by uneven settlement. Eliminating that characteristic of conventional bridge systems is a key feature of the new technology.

Watch video highlights of the demo


Imagine replacing the derivatives of crude oil needed to produce conventional asphalt with renewable, cost-competitive, regionally produced, and high-performing materials derived from non-food biomass such as switchgrass, hybrid poplar, or cornstover. The idea portends a whole new world of possibilities and likely could stand the traditional petroleum-based economy on its head.

Researchers at Iowa State University are doing just that, producing bio-oil and bio-char through a process called fast pyrolysis. New bio-oil fractionation technologies also developed at ISU separate the bio-oil into different fractions—some of which appear to be ideal materials for asphalt.

In addition to developing thermoplastic elastomers (polymers) from vegetable oils—which offer many transportation-related applications—ISU researchers are examining and exploring the "bioeconomy," from all phases of the production process to product development and diversification opportunities.

Such collaborative opportunities involving transportation and the bioeconomy were featured during a half-day TERRA Innovation Series event in August at Iowa State University in Ames, Iowa.

A bioeconomy makes use of biorenewable resources, including biomass, for the production of chemicals, fuels, materials, and energy to sustain economic growth and prosperity. Iowa State's bioeconomy research is cross-disciplinary and includes research groups from the areas of agriculture, plant sciences, agricultural engineering, agricultural economics, mechanical engineering, chemical and biological engineering, civil engineering, and numerous others.

Read the full article in the October issue of TERRA E-News.

A conversation with the new head of civil engineering

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Joe Labuz

Earlier this year Professor Joe Labuz accepted a five-year appointment as head of the Department of Civil Engineering. Labuz served as interim department head since July 2012 and as a member of the faculty since 1987. He has conducted more than 20 transportation-related research projects in the areas of pavements, soils, and structures and has also served students as the director of both undergraduate and graduate studies. Below he shares his vision and directions for the department.


I am very much looking forward to my tenure for a number of reasons: the faculty are among the world leaders in their fields; our students more than ever are focused on developing skills that can be used to serve society; and the college is committed to supporting and rewarding cutting-edge research and quality instruction.

I should first acknowledge the previous head, Professor Roberto Ballarini. Through his leadership, the department experienced growth in research expenditures and student satisfaction. His vision was one of excellence in all that we do.

I will try to continue his legacy of excellence, while striving for my vision of building—building progressive educational programs in civil engineering, environmental engineering, and geoengineering; building research thrusts that are aligned with regional and state priorities; and building a vibrant, cohesive department where faculty and students are recognized nationally and internationally for distinguished academic achievement.


One of my first priorities is to build a state-of-the-art measurements laboratory for hands-on learning and instruction. Just as numerical modeling has become a common thread of engineering analysis and design, so too should sensing be a component of our core programs.

New degree program

Furthermore, the department is proposing a new degree program, the first in Minnesota: bachelor of environmental engineering (BEnvE). This reflects the extensive interests of our faculty and students in forwarding environmental issues within a civil and geoengineering paradigm. Our interests span from clean energy to water treatment, from hazardous waste to groundwater remediation, to name a few. The introduction of this program aligns us with many other leading civil engineering departments nationwide.

Name change

Perhaps the most exciting news is the name change to Department of Civil, Environmental, and Geo- Engineering. The proposed name will better reflect the character of the department and readily identify our degree programs. Note that the name will be unique in the U.S. The name change, when approved by the Regents, will be official on July 1, 2014.


On the research side, several initiatives are focused on issues important to the region and nation. Measurement and analysis of transportation infrastructure, environmental restoration of lakes and streams, and renewable energy such as wind and biofuels have substantial funding in the department, and resources such as faculty hires and laboratory space are being dedicated to these thrust areas.

CE building and labs

Finally, the building itself is being renovated and some laboratories are being remodeled, as is the second floor student lounge, through the generous support of WSB & Associates and the College of Science & Engineering. The unique underground structure received the 1983 outstanding civil engineering achievement award from ASCE. I look forward to inviting the community to visit sometime in December 2013 to celebrate the 30-year anniversary.

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Center for Transportation Studies

University of Minnesota

200 Transportation & Safety Building

511 Washington Ave SE

Minneapolis, MN 55455

Phone: 612-626-1077

Fax: 612-625-6381


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