For more than 50 years, the Local Road Research Board (LRRB) has brought important developments to transportation engineers throughout Minnesota. Those developments range from new ways to determine pavement strength to innovative methods for engaging the public. Today, the LRRB remains true to its important mission: supporting and sharing the latest transportation research applications with the state’s city and county engineers.

Hot Topics

Traffic Sign Replacement Research

Traffic sign replacement is a tricky business. Waiting too long might endanger lives and expose an agency to a lawsuit. But replacing traffic signs prematurely could cost a single city tens of thousands of dollars per year. If fully implemented, new recommendations developed by MnDOT and the Local Road Research Board (LRRB) could save public agencies as much as $41 million over three years by helping them better manage their signs and meet new federal requirements on retroreflectivity without replacing signs prematurely. A recent LRRB study, which consulted other states’ research and examined signs in the field, determined that the life of the modern sign in Minnesota is at least 20 years, and signs may retain their retroreflectivity for 30 years or more. A test deck at the MnROAD facility will track the condition of Minnesota signs over the next decades — and perhaps push the recommended replacement cycle longer.
To read the full article on the Crossroads blog, click here.
For further details, see the full Report, Technical Summary, or
Traffic Sign Maintenance Handbook
March 12, 2015

New LRRB At-A-Glance

Check out the latest At-A-Glance report detailing LRRB's accomplishments during fiscal 2014. The publication includes research highlights, budget summary, categorized lists of projects, staff contact info, and descriptions of new videos and research syntheses.
FY2014 At-A-Glance
FY2013 At-A-Glance
FY2012 At-A-Glance
January 30, 2015

Pedestrian Crossing: Uncontrolled Locations

A new guidebook has been developed to help Minnesota transportation agencies evaluate their uncontrolled pedestrian crossings and determine appropriate treatment options. Funded by the Minnesota Local Road Research Board, the guidebook – Pedestrian Crossings: Uncontrolled Locations – is intended to offer agencies a consistent methodology for evaluating uncontrolled pedestrian crossing locations on their roadways. The book recommends when to install marked crosswalks and other enhancements at uncontrolled locations based on a number of factors, including average daily vehicle count, number of pedestrians, number of lanes and average vehicle speed.
Click here to read the full article.
Click here to access the guide, data collection worksheets and the full research report.
December 24, 2014