A new method of testing low-temperature cracking in asphalt pavement shows promise for design, quality control and quality assurance. Test results produced by the new method, which is faster and less expensive than the previous method, match well with results from the older method.
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Urban Rapid Transit Reduces Traffic on Nearby Roads
Light rail transit and bus rapid transit in the Twin Cities provide urban residents with fast, safe and reliable transportation. These transitways have the potential to attract more riders and further reduce automobile traffic, relieving the growth of congestion on nearby roads as people decide to be transitway passengers rather than motorists.
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Strategies for Recruiting and Retaining Minnesota’s Transportation Workforce
Across the transportation industry, public and private employers are experiencing workforce shortages and an uncertain future. As older employees retire and younger workers fill their roles, organizations must naturally adjust to accommodate their changing workforce. In the transportation industry, shifting demographics have also brought new attitudes regarding technical jobs. The result is that fewer engineers and other highly skilled professionals are entering the field, and keeping those who do is becoming increasingly difficult. To address this changing landscape, transportation agencies of all sizes must be prepared to meet the challenges ahead or risk falling behind.
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Evaluating the Impact of J-Band on Pavement Service Life and Crack Resistance
Potholes and other pavement failures in asphalt typically occur at the seams between lanes, where the mixture loses density during compaction because the edges are not confined like they would be with cement concrete forms. Researchers found that spraying J-Band, a void-reducing asphalt membrane (VRAM), in a band along longitudinal joints before asphalt layers are applied increased bond strength, lowered permeability and air void levels, and improved crack resistance.
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Investigating Asphalt Pavement Stripping Under Seal Coats
A recent Local Road Research Board (LRRB) study confirmed that increased freeze-thaw activity during Minnesota winters leads to delamination of seal coats from underlying pavements. Researchers identified optimal seal coat mix combinations and site conditions that may ensure effective seal coating of asphalt pavements in cities and counties around Minnesota.
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Evaluating “Hot Shots”: Winter Roads Treatment of Hardest Icy Spots
A new six-part video series, “Hot Shots for Cold Climates” explores treating Minnesota’s iciest roadways, with safety and environmental impact in mind.
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Local Guidance for Bicycle Facility Design
A quick reference guide is now available to help local agency planners and designers select the best bicycling facilities for their system. This guide walks local agencies through the selection and design process, and directs users to specific places within design manuals for details on facility questions.
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Assessing Bridge Barriers for Today’s Vehicle Needs
In a recent study of inspection reports, design documents and other data to evaluate the safety performance of bridge barriers, investigators found that the most commonly used barrier designs meet newer safety requirements and keep Minnesota drivers safe.
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Smartphone App Gives Crossing Guidance to the Visually Impaired
In a recent research project, MnDOT sought to validate a smartphone app designed to guide pedestrians who are blind or visually impaired through signalized and unsignalized intersections. The project succeeded in showing the app’s effectiveness in tests at six intersections in Stillwater, Minnesota.
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Low-Volume Road Runoff Analyses Suggest Optimal Treatments
Assisted by many county agency staff, researchers collected and analyzed runoff from low-volume rural roads over two years to determine how their contaminants compared to those of high-volume roadways. Results documented that runoff from low-volume roads has a lower contaminant concentration and that ditches and swales can be used to effectively treat rural road runoff.
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