Research that could change the Way We Work

Some top picks from Transportation Research Board’s papers presented at its 90th annual meeting in D.C.

By Tom Kuennen, Contributing Editor

It is always a meeting filled with new ideas and stunning research breakthroughs in the transportation industry. This year was no exception. A lot of the research stood out. We have assembled this selection based on space and the works’ potential value to readers.

In daylight, lighted pavement markers resemble raised pavement markers as they define the adjacent three left-turn lanes in Sugarland, Texas.

Eurostyle wet-on-wet, two-lift PCC/PCC paving was tested in 2010 at the Minnesota Road Research Project (MnROAD), the world’s largest and most comprehensive outdoor pavement laboratory. This paving technique was discussed on these pages in 2008 (see Roadbuilders to Get Fresh Look at Two-Lift Concrete Paving, June 2008, pp. 22-29).

Now we know more about PCC/PCC paving in the United States. In a paper at the 90th annual meeting of the Transportation Research Board in Washington, D.C., held this January, research at MnROAD demonstrated that two-lift, PCC/PCC paving has potential benefits in terms of durability, and can be executed with existing concrete production and paving infrastructure in this country, but glitches must be resolved.

At night, lighted pavement markers provide positive guidance to drivers in the three adjacent left-turn lanes, reducing errors and lane-keeping violations.

That paper was one of more than 4,000 scheduled presentations and peer-reviewed papers on every facet of multimodal transportation construction, materials, policy and operations presented at the TRB meeting, and Better Roads was there.

Following is a brief wrap-up of some of the most interesting research for the readers of Better Roads. For more information, visit www.trb.org.

MnROAD Examines Two-Lift PCC/PCC Slipform Paving

Two-lift PCC/PCC paving will work in the United States, but practical issues will have to be worked out, say Derek Tompkins, associate director, Pavement Research Institute, University of Minnesota-Minneapolis; Mary Vancura, research associate, University of Minnesota; Shreenath Rao, senior engineer, Applied Research Associates, Champaign, Ill.; Lev Khazanovich, associate professor, Department of Civil Engineering, University of Minnesota; and Michael I. Darter, principal engineer, Applied Research Associates, in their paper, Construction of Sustainable Pavements: Two-Layer Concrete Pavements at the MnROAD Facility.

“Recent efforts under the Strategic Highway Research Program (SHRP 2) project R21, Composite Pavements, led to the design and construction of composite portland cement concrete pavement sections at the Minnesota road research facility,” the authors write. Part of the R21 work includes research into a composite pavement system featuring a thin portland cement concrete (PCC) layer immediately placed over another PCC layer.

“The goals of that research,” they write, “were to determine the behavior and identify critical material and performance parameters for PCC/PCC; develop and validate performance models and design procedures consistent with the Mechanistic-Empirical Pavement Design Guide; and recommend specifications, construction techniques and quality management procedures.”

Dynamic message sign installed 900 feet ahead of intersection displays allow travel movements for the three left-turn lanes, and alternate message reminding drivers to stay in their lane.