Tag Archives: roadway safety

Roadway Safety Institute seminar series begins September 10

The Roadway Safety Institute will kick off its safety-focused seminar series on September 10 in Minneapolis with a presentation on the Minnesota Strategic Highway Safety Plan by Brad Estochen, MnDOT state traffic safety engineer.

Seminars will be held Thursdays from 3–4 p.m. throughout the fall semester on the U of M’s east bank campus. The free seminars, which will also be streamed live on the web, will feature the latest work of Institute researchers and other industry experts.

Detailed information about seminar topics and speakers will be available soon on the Institute website, or you can subscribe to receive e-mail updates from the Institute.

Hope to see you there!

Seminar Schedule

September 10 — Minnesota Strategic Highway Safety Plan
Brad Estochen, State Traffic Safety Engineer, Minnesota Department of Transportation

September 17 — Characterizing Uncertainty in Left-Turn Crash Reconstructions Using Event Data Recorder Data
Gary Davis, Professor, Department of Civil, Environmental, and Geo- Engineering, University of Minnesota

September 24 — Transportation Incidents, Events, and Disasters
Dan Work, Assistant Professor, Department of Civil Engineering, University of Illinois at Urbana-Champaign

October 1 — Low-Cost Centimeter-Accurate Mobile Positioning
Todd Humphreys, Assistant Professor, Department of Aerospace Engineering and Engineering Mechanics, University of Texas at Austin

October 8 — Title TBD
Linda Boyle, Professor, Department of Civil and Environmental Engineering, University of Washington

October 15 — Speaker TBD

October 22 — Automated Identification and Extraction of Horizontal Curve Information from GIS Roadway Maps: Improving Safety on All Roadways
David Noyce, Professor, Department of Civil and Environmental Engineering, University of Wisconsin–Madison

November 5 — Novel Collision Avoidance System for Bicycles
Rajesh Rajamani, Professor, Department of Mechanical Engineering, University of Minnesota

November 12 — Assessing Roadway Safety Risks in American Indian Reservations
Kathy Quick, Assistant Professor, and Guillermo Narvaez, Research Associate, Humphrey School of Public Affairs, University of Minnesota

November 19 — Pedestrian Safety, Pedestrian Behavior, and Intersection Design and Control
Per Garder, Professor, Department of Civil and Environmental Engineering, University of Maine

December 3 — Title TBD
Don Fisher, Professor, Department of Mechanical and Industrial Engineering, University of Massachusetts Amherst

December 10 — A Positioning and Mapping Methodology Using Bluetooth and Smartphone Technologies to Support Situation Awareness and Wayfinding for the Visually Impaired
Chen-Fu Liao, Educational Systems Manager, Minnesota Traffic Observatory, University of Minnesota

Six effective low-cost safety improvements for roads

For the past 10 years, Minnesota and 37 other states have pooled their resources to test the effectiveness of roadway safety improvement strategies. The project, appropriately titled “Evaluation of Low-Cost Safety Improvements,” evaluates key strategies laid out in a national guidebook aimed at reducing the number of annual highway deaths.

Participating states say the project, which has now been extended a total of eight times beyond its original scope, has been a resounding success. MnDOT Safety Engineer Brad Estochen said the pooled-fund study has provided state DOTs much-needed evidence to gain support for implementing new safety improvements.

“Some states want to do a certain strategy, but don’t have the institutional support,” Estochen said. “Through the collaboration of the Peer Exchange, they have national results they can point to.”

We asked Estochen, MnDOT’s technical liaison for the pooled fund, to name his top strategies to come out of the study.

Traffic calming measures

Roadway

One phase of the study used simulated driving scenes to examine methods of traffic calming (i.e., getting drivers to slow down) in  rural towns. The research found that drivers were most impacted by chicanes — extra curves in the road — and the presence of parked cars on the street. An alternative strategy, curb extensions (also called “bulb-outs”), was found to offer only a small potential safety benefit or no benefit at all.

(Read more about this phase of the study.)

Nighttime visibility improvements

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Researchers also looked at ways of improving nighttime driver visibility on rural roads. Edge lines and post-mounted delineators were selected as the best alternatives for improving curve visibility at night, with curve detection improving 12 percent to 70 percent due to enhanced edge lines. The results are significant, since horizontal curve sections of two-lane rural roads are a major source of roadway fatalities.

(Read more about this phase of the study.)

Flashing beacons at stop-controlled intersections

One way to make drivers aware that they’re approaching a stop sign is to add a flashing beacon to the intersection. Researchers installed various configurations of flashing beacons at more than 100 sites in North and South Carolina and examined the crash data before and after installation.

Courtesy of K-Kystems
Courtesy of K-Kystems

Results indicate that standard flashing beacons, as well as some “actuated” beacons (i.e. those that only turn on when traffic is approaching the intersection), are not only effective at reducing crashes, but also economically justifiable based on cost-benefit calculations.This research helped pave the way for more widespread adoption of Minnesota’s Rural Intersection Conflict Warning Systems (RICWS).

(Read more about this phase of the study.)

Edgeline rumble strips

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Edgeline rumble strips on curves were shown to significantly improve safety in the third phase of the study, which tested a variety of techniques.

Whereas rumble strips are traditionally ground into centerline or on the shoulder, Kentucky and Florida experimented with placing rumble strips right along the white edgeline of curved sections of road. This method was shown to reduce overall crashes by 29 percent.

(Watch the FHWA website for updates on this phase of the study.)

Red light enforcement devices

Red light indicator
In Florida, crashes due to people running the red light fell by 33 percent thanks to a small light that turns on when the signal turns red. This little light bulb, which is placed on top of a signal, allows for a police officer to sit at the other end of the intersection rather than pursue a car right through the intersection. Not only is it safer, but motorists are also more likely to obey the signal if they know police might be watching on  the other side.

Researchers are also still collecting data on the other techniques studied in phase three, including surface friction treatments on curves and ramps and larger curve warning signs (called chevrons). Watch the FHWA website for updates.

Wider roads in rural areas

manufacturing

Could simply shifting the edge lines of a rural road reduce the number of accidental drive-offs?

Yes, according to this study, which evaluated the effectiveness of various lane-shoulder width configurations on rural, two-lane undivided roads using data from Pennsylvania and Washington.

In general, results were consistent with previous research, showing crash reductions for wider paved widths, lanes and shoulders. For specific lane-shoulder combinations, the study found a general safety benefit associated with wider lanes and narrower shoulders for a fixed pavement width; however, there are exceptions. The report has a chart that shows the optimal lane-shoulder combinations for different sizes of roads.

In theory, there should be no additional cost for these strategies, as an edgeline can be re-striped as part of an existing resurfacing project.