All posts by mndotresearch

Quantifying the Benefits of Improved Compaction

Compaction is the final and most critical step in asphalt pavement construction. National research conducted several years ago indicated that a slightly more compact pavement than typical could help roads last longer. To understand the relationship between pavement density and long-term performance, MnDOT has built a database with performance data from samples collected soon after they were constructed more than a decade ago. The agency hopes to eventually have enough data to determine the right amount of compaction. 

Continue reading Quantifying the Benefits of Improved Compaction

Quantifying the Effect of Geogrids in Asphalt Pavement Foundation Layers

Geogrid inserted between the layers of asphalt pavement during construction can increase the strength and durability of the finished road. To help engineers decide whether to use geogrids in road construction projects, researchers calculated just how much strength and durability geogrid material can add to an asphalt pavement and integrated the findings into MnDOT’s design software.

Continue reading Quantifying the Effect of Geogrids in Asphalt Pavement Foundation Layers

Innovative Materials and Technologies for Sustainable Pavement Infrastructure

In search of enhanced pavement damage detection practices, researchers investigated two innovative additives to asphalt binders: graphite nanoplatelets and taconite concentrates. They also examined the ability of microwave energy to restore subsurface cracking.

Continue reading Innovative Materials and Technologies for Sustainable Pavement Infrastructure

Investigating Pavement Segments With Long-Term Poor Ratings

Researchers investigated pavement segments within MnDOT’s pavement management system that had received a poor ride quality level rating for more than five years. Their investigations showed that for most segments, the true pavement conditions differed from listed ratings due to the pavement segments’ unique characteristics.

Continue reading Investigating Pavement Segments With Long-Term Poor Ratings

Effect of Real-Time Winter Road Condition Messages on Driver Behavior

To help make roads as safe as possible in winter, MnDOT uses dynamic message signs (DMS) to display weather advisories to drivers. Using DMS to display real-time road condition information could further enhance safety by potentially resulting in reduced driving speeds and safer following distances. Roadside pavement sensors can provide real-time road condition data for these warning messages, alerting drivers to conditions ahead.

Continue reading Effect of Real-Time Winter Road Condition Messages on Driver Behavior

How Did COVID-19 Affect Driver Safety?

The COVID-19 pandemic resulted in fewer drivers on Minnesota’s roads in 2020 than in the previous year. Emptier roadways seem like they should be safer, but many states measured increases in speeding. For example, California issued twice as many speeding tickets, Iowa reported a 65% increase in driving 25 mph or more over the speed limit, and Ohio experienced the highest number of traffic fatalities since 2007. Clearly, some drivers were taking advantage of empty streets to speed. The pandemic also strained police forces, resulting in less enforcement.

Continue reading How Did COVID-19 Affect Driver Safety?

Evaluating Improved Specifications for Retightening Anchor Rods on Support Poles

In this follow-up study, researchers checked the effectiveness of revised specifications for tightening anchor rods on sign and signal support poles. The revised specifications will ensure correct tightening procedures, which will result in better installations and maintenance.

Continue reading Evaluating Improved Specifications for Retightening Anchor Rods on Support Poles

Using Noise Barriers and Snow Fencing to Capture Solar Energy

During the past decade, MnDOT has been developing solar projects and actively pursuing cost-effective energy-efficiency measures. Among the potentially effective innovations the agency has considered is adding solar panels to noise barriers and snow fences, transforming these single-function installations to multifunction installations. The electricity generated from this practice could offset installation costs and eventually generate revenue for other purposes. 

Continue reading Using Noise Barriers and Snow Fencing to Capture Solar Energy

New Resource for Manhole and Catch Basin Installation

Finding resources that address manhole and catch basin issues occurring in Minnesota can be challenging. In a recent project, researchers surveyed 83 municipalities and interviewed other engineers and product representatives to gather data about manhole and catch basin installation and maintenance practices. The resulting report provides current information for municipal engineers about these essential installations.

Continue reading New Resource for Manhole and Catch Basin Installation