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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

Guide for Rural Intersection Safety Technologies

A new guidebook is intended to help engineers select and deploy LED stop signs and ICWS at STOP-controlled intersections. In addition to the complete guidebook, products include a six-page quick guide and an appendix of example plans for conflict warning systems and LED stop signs. View informational flyer for more information.
August 4, 2016

Effects of Implements of Husbandry on Local Roads

The LRRB has produced a brochure that provides background information on the history of implements of husbandry; summarizes neighboring states’ weight restrictions; and provides links to recent research data on the damaging effects that large machinery has on pavements.
Print brochure
Online brochure
August 4, 2016

Flashing Yellow Arrow Tutorial Video

The Local Road Research Board recently developed a spreadsheet tool to assist local agencies determine which hours of the day to consider using flashing yellow arrow (FYA) phasing. An instructional video has now been published to help agencies understand the methodology used to develop the spreadsheet, as well as how to use it. The instructor walks users through an example intersection and describes the inputs needed and how to interpret the results. The spreadsheet and video are tools to assist engineers with decision making regarding FYAs, but engineering judgment should be used to make the final decision.
Tutorial Video
View Report
Technical Summary
Download Spreadsheet Tool
Spreadsheet Instructions
View Flyer
July 27, 2016