Tag Archives: LRRB

NCITE Webinar: LRRB Mini-Roundabout Guidance

July 19, 2024 Julie Swiler Leave a comment

Tuesday, August 6, 10-11 a.m., free to attend

Increasingly, local agencies are opting for mini-roundabouts for some locations instead of traditional roundabouts, which typically require a larger footprint than a standard four-way intersection. Mini-roundabouts are characterized by a small diameter and fully traversable islands (central island and splitter islands).

Join the Apex Engineering Group for a presentation on the Local Road Research Board project, Mini-Roundabout FAQs. Project team members Michael Marti and Zach Heimer with SRF Consulting Group and Jon Pratt with the City of Detroit Lakes will discuss this new guidance.

The guidebook defines mini and compact roundabouts and provides selection criteria on when to use them as well as details regarding the center treatment. The FAQ format provides easy navigation to technical information.

Join the webinar

If you have difficulty accessing the meeting, use the meeting ID and passcode:

Meeting ID: 251 050 866 163
Passcode: tGP6ix

Materials and Construction, Research

New Project: Long-Term Field Performance Evaluation of Chip Seals

July 10, 2024 Malee Yang Leave a comment

Chip seals are an economical road surface treatment that MnDOT and counties use to enhance existing pavement performance and service life. A thin layer of asphalt emulsion sprayed on the pavement surface and mixed with aggregate chips can address minor pavement distresses and seal the pavement surface to reduce the impacts of further wear.

Continue reading →

Materials and Construction, Research

Finding High-Performing Aggregate Bases for Long-Lasting Pavement

May 1, 2024 mndotresearch Leave a comment

Two county roads provided a testing ground for three combinations of aggregate bases and asphalt binders. Results from more than two decades of research and monitoring of pavement test sections validated previous conclusions. A larger gradation aggregate base showed superior performance over the pavement life cycle when compared with the standard aggregate base. Additionally, sections constructed without transverse joints to allow natural thermal cracking outperformed sections with sawn and sealed joints.

Continue reading →

Policy and Planning, Research, Traffic and Safety

Effectively Alerting the Public About Local Road Closures

April 24, 2024 Malee Yang Leave a comment

Navigation apps can be valuable timesavers for drivers in Minnesota. To maximize their use, these apps need traffic information that is timely and accurate. While state highway closures are reported effectively, reporting road closures on local roads and highways is inconsistent. This project aimed to improve local road closure reporting by exploring the development of a streamlined reporting system and creating guidance for reporting local road closures to third-party navigation apps.

Continue reading →

Materials and Construction

New Project: Improving and Developing Pavement Design Inputs and Performance Functions for Cold Recycled Pavement Layers

March 28, 2024 Julie Swiler Leave a comment

Local agencies in Minnesota use cold recycling technologies for flexible pavement rehabilitation because of their economic and environmental benefits. The three main methods are cold in-place recycling (CIR), cold central plant recycling (CCPR), and stabilized full-depth reclamation (SFDR).

Continue reading →

Traffic and Safety

New Project: Development of a System to Report School Bus Stop Arm Violations

February 29, 2024 Julie Swiler 2 Comments

When a motorist ignores an extended school bus stop arm, it creates a direct and serious risk to children boarding and exiting a school bus. Capturing information about such incidents is a critical step in better understanding why they occur and how they can be prevented.

Continue reading →

Traffic and Safety

New Project: Evaluation of Static and Dynamic No Right Turn on Red Signs at Traffic Signals

February 15, 2024 Julie Swiler 1 Comment

Making signalized intersections safer for pedestrians can be achieved by reducing points of conflict between pedestrians and vehicles. One source of conflict occurs when a vehicle makes a right turn on red (RTOR) onto a street in which pedestrians are crossing. During this turn, the driver must cross the path of pedestrians while at the same time searching for gaps in conflicting vehicle flow.

Continue reading →

Maintenance Operations

Drainage 101: Understanding and Managing Drainage Issues

February 6, 2024 mndotresearch Leave a comment

Increased regulation and rising levels of precipitation have made stormwater management a more routine and time-consuming issue than in previous decades. A new resource provides guidance and best practices that will help city and county engineers, local officials and private property owners navigate the complex, often public-facing issues related to recurring drainage problems and stormwater management.

Continue reading →

Materials and Construction

Adapting Asphalt Mixtures for Tougher Rural Roads

January 25, 2024 mndotresearch 2 Comments

Seasonal and daily temperature variations, freeze-thaw cycles and other environmental factors lead to pavement distress on low-volume rural roads. Modifying asphalt mixtures could improve pavement resistance to these environmentally driven distresses. A comparison of the mechanical properties and performances of selected asphalt mixtures identified a mixture and method that hold considerable promise for improving performance and longevity on low-volume roads.

Continue reading →