Docs

“Access management” refers to the design, implementation and management of entry and exit points (i.e., driveways, entrances or exits) between roadways and adjacent properties. These entry and exit points can be managed by careful planning regarding their location, the types of turning movements allowed, and if appropriate, medians that provide or prohibit access to the driveways. Developing and implementing effective access management strategies that promote or improve safety requires considering the location of driveways in the context of current and future access needs, current and future intersection operations, and mobility for pedestrians and bicyclists.

This link contains materials for developing an ADA transition plan and links to two webinars by Minnesota LTAP on this topic.

This handbook serves as an illustrated guide to assist users in detecting and distinguishing ASR in the field on concrete roads and bridges from other types of damages.

Provides some information and perspective from stormwater managers who have seen such projects in their own communities, and things to think about as you consider alternative approaches.

This report summarizes the findings of a study identifying signing and marking strategies that resulting higher levels of comprehension and compliance in lane selection on the approach of roundabouts and examines the effects of these strategies on lane use after an approach lane has been selected.

The objectives of this study were 1) to identify the factors that contribute to accidents caused by failure to stop and failure to yield the right-of-way at rural two-way stop-controlled intersections on the state highway system, and 2) to determine what traffic control devices or other measures could be effective in reducing the frequency of these accidents.

This document provides guidance for American Disabilities Act required pedestrian access in work zones.

This safety brief from FHWA describes the systemic approach to road safety. Typically, systemic safety improvements are low-cost, require little maintenance, have documented crash reductions, address specific crash types or crash risk factors, and are implemented at multiple locations with the same characteristics.

This report describes the best practices used in developing cost estimates and provides guidance for overseeing the development of such estimates. It serves as a line of communication among different State and Federal agencies involved in the creation and oversight of cost estimates. Private parties, such as contractors and consultants, can also benefit from the product of this research. The final products of this report are a series of flowcharts and checklists designed to aid agency personnel in overseeing cost estimates at a program and project level and aid in developing and overseeing cost estimates at multiple stages of projects and programs.

This comprehensive plan lays out U.S. DOT’s multimodal strategy to promote collaboration and transparency, modernize the regulatory environment, and prepare the transportation system for the safe integration of automated vehicles. It illustrates how the Department’s work extends beyond government to meet the challenges of a modern transportation system by providing real-world examples of how the Department’s operating administrations collaborate to address the needs of emerging technology applications.

Provides background information on Kansas stormwater regulations related to road and bridge operations. Companion piece to the article in KUTC Newsletter, Fall 2008 issue, on the topic.

This report presents information about the use of the mechanistic-empirical procedure (MnPAVE) in designing hot-mix asphalt pavements in Minnesota. Researchers developed the MnPAVE software program using information from the Minnesota Road Research Project (Mn/ROAD) test facility and from 40-year-old test sections around Minnesota. MnPAVE procedures use Equivalent Standard Axle Loads (ESALs) to evaluate traffic loading, and the report includes methods to estimate these values for design purposes over a 20-year design life, as well as a procedure to measure vehicle type distributions. In addition, the report presents an evaluation of subgrade soils for each thickness design procedure, summarizes Minnesota Department of Transportation specifications that relate to embankment soil construction and to the construction of the pavement section materials, and recommends specific density or quality compaction using a control strip. It also includes best practices on setting up projects most effectively to follow specifications.

This manual is intended for practical use by trail maintenance managers. It will also be useful for policymakers who are tasked with anticipating and planning for maintenance budget and personnel needs.

This website will serve as your one-stop shop for FHWA’s implementation of the Bipartisan Infrastructure Law, including everything from fact sheets and funding notices to guidance, regulations, and presentations.

This video demonstrates how to patch damaged asphalt with more material and a motograder to smooth and compact it.

The CARMA Ecosystem has created six new message types to enable vehicle-to-everything (V2X) communication between vehicles and other entities for various CDA cooperation classes, as defined in SAE J3216,1 which enables true cooperative behavior.

Describes research on centerline rumble strips, including research conducted in Kansas, and potential advantages and disadvantages of using the strips.

This video introduces seven management practices that local government agencies may use to meet state and federal stormwater regulations. Based on a Minnesota Local Road Research Board guide to stormwater best management practices, the video shows examples of various BMPs as local engineers explain how they have used them to keep stormwater pollutants out of Minnesota lakes and streams.

This brochure provides practical tips for how to talk about road safety with local elected officials. It includes a link to a video on the topic, as well.

This fact sheet will provide general tips for building interest and buy-in for active transportation, advice and examples from other Kansas communities, and ideas for how to maintain and continue to grow momentum once community interest in active transportation has been established.

Provides helpful tips and community profiles on designing streets to meet the needs of all users and offers a flexible planning process to suit each community's situation.

An overview of the history of the US transportation system.

Examines the cost-effectiveness of transit in Kansas, based on current work by the National Center for Transit Research on the cost-effectiveness of transit nationwide.

This manual outlines the state of the art and recommended practice for designing and constructing geosynthetic reinforced soil (GRS) technology for the application of abutments and the Integrated Bridge System (IBS). It was developed to provide engineers with the necessary background knowledge of GRS technology and its fundamental characteristics as an alternative to other construction methods. This manual presents step-by-step guidance on the design of GRS-IBS using the Load and Resistance Factor Design methodology. Material specifications for standard GRS-IBS are also provided. Detailed construction guidance is presented along with methods for the inspection, performance monitoring, maintenance, and repair of GRS-IBS. Quality assurance and quality control procedures are also covered. The procedures presented are based on 40 years of State and Federal research and deployment efforts focused on GRS technology for bridge support

This manual has been developed to help Iowa highway engineers improve the design, construction, and testing of a pavement system's subgrade and subbase layers, thereby extending pavement life. It synthesizes current and previous research conducted in Iowa and other states into a practical geotechnical design guide and construction specifications. Topics covered include the important characteristics of Iowa soils, the key parameters and field properties of optimum foundations, embankment construction, geotechnical treatments, drainage systems, and field testing tools.

This guidebook provides information on the best practices in bus stop design, covering both urban and rural areas. It includes recommendations for designing stops with and without sidewalks, curb cuts, ramps, stairs, and shelters. Illustrations of recommended designs are included in the attached appendices.

This article provides some useful tips for basic bus stops, so they can become a safe, inviting, and functional part of the transportation program.

The primary objective of the study is to fill the gaps in the data available from the NTD database to determine the demand-response transit level of service. Also, this study aims to develop a standard method for determining the demand-response service level of coverage so that geographic areas/locations that do not have sufficient demand-response transit service can be identified. A survey questionnaire was developed to gather important information such as service span, service area, service type, and service eligibility from demand-response operators to determine the demand-response transit level of service. The survey was tested in two states, North Dakota and Florida, for its applicability in the rest of the country, and recommendations were provided for gathering additional service details for determining the national demand response transit level of service.

This report describes a Bayesian method for estimating accident rates at individual sites, which takes into account the fact that the total traffic count usually used to measure exposure is generally not known with certainty.

This publication is a companion to the technical assistance brief “Getting Started: Creating a Vision and Strategy for Community Transportation.” That preliminary document describes the process for building a foundation of values, needs, vision, strategy, and community commitment for transit, one that ensures that the transit system’s mission and goals are clearly stated and understood by all.

Left-turn movements at intersections, including driveways—especially movements that are made from lanes that are shared through traffic—cause delays and adversely impact safety. Although left-turn warrants have been updated, many agencies still use research performed by M. Harmelink from the mid-1960s. While most states use procedures that are based on Harmelink, a number of limitations of Harmelink’s procedure have been identified. Economic analysis can provide a useful method for combining traffic operations and safety benefits of left-turn lanes to identify situations in which left-turn lanes are and are not justified economically. This project used a benefit-cost approach to determine when a left-turn lane would be justified. The steps included simulation to determine delay savings from installing a left-turn lane, crash costs and crash reduction savings determined from safety performance functions and accident modification factors available in the Highway Safety Manual, and construction costs. Left-turn lane warrants were developed for rural two-lane highways, rural four-lane highways, and urban and suburban roadways. In addition, warrants for bypass lanes were developed for rural two-lane highways. A Design Guide on Left-Turn Accommodations at Unsignalized Intersections was developed that discusses left-turn lane designs, traffic control treatments, and case study examples.

Little is known about how driving performance and attention change over time with increased automation. The current study assessed the effect of varying levels of vehicle automation on driver performance over time. Participants gained experience with advanced driver assistance systems (ADAS) across four sessions in the driving simulator. The specific driver assistance system was manipulated between subjects and included cooperative adaptive cruise control (CACC), lane-keeping assist (LKA), a combination of CACC and LKA (CACC + LKA), and a control condition with no driving assistance features. Adaptation was assessed by measuring drivers' response to uneventful roadway conditions and unexpected critical events during both earlier and later exposure to the technology. Overall, the results of the current study paint an optimistic view of driver assistance technology. Participants who used the technology were able to do so in a way that benefited their driving performance and allowed them to direct more of their attention to the road ahead. Further, driver adaptation was not associated with impaired responses to emergency events. The results suggest that Level 1 driver assistance systems have the potential to benefit driver safety even after drivers have adapted to the technology following repeated use.

This report describes the results of the focus group portion of this research. The objective of the focus groups was to identify driver attitudes and behaviors related to intersection safety and to assess the likely impacts of new or existing infrastructure-based technologies/countermeasures.

This report presents the results of a project aimed at creating the prototype for a searchable (web-based) database of public transit investment projects and their associated (transit-driven) economic and land development outcomes. The purpose of this system is to provide transportation planners with a consistent base of data on actual, documented economic and land development impacts of completed transit-related investments, along with a narrative describing the form of impact and factors that affected it.

Effective erosion control requires an integrated approach, which considers government statutes and regulations, a broad knowledge of temporary and permanent erosion control methods; design, construction, and maintenance considerations; and new technology. All of those elements are included in this manual.

This study identified 58 roundabout corridors in the United States in 2011. There is diversity among these corridors in terms of length, roundabout spacing, number of lanes, surrounding land use, previous control (if not a new facility), and reasons for the selection of roundabouts.

Dynamic speed feedback sign (DSFS) systems are one method to reduce vehicle speeds and, consequently, crashes on curves. These systems show promise but they have not been fully evaluated on curves. The Center for Transportation Research and Education at Iowa State University conducted a national demonstration project to evaluate the effectiveness of two different DSFSs in reducing speed and crashes on curves at 22 total sites on rural two-lane roadways in seven States. The goal is to provide traffic safety engineers and other professionals with additional tools to manage speeds and crashes on rural horizontal curves more effectively.

A road diet involves narrowing or eliminating travel lanes on a roadway to make more room for pedestrians and bicyclists. (1) While there can be more than four travel lanes before treatment, road diets are often conversions of four-lane, undivided roads into three lanes—two through lanes plus a center turn lane (see figure 1 and figure 2). The fourth lane may be converted to a bicycle lane, sidewalk, and/or on-street parking. In other words, the existing cross-section is reallocated. This was the case with the two sets of treatments in the current study. Both involved conversions of four lanes to three at almost all sites.

In this research, two promising low-cost rural intersection countermeasures were selected and evaluated for their impact on safety: post-mounted beacons and retroreflective strips on stop signposts. The post-mounted beacons were set to activate only when an approaching vehicle’s speed surpassed a predetermined threshold.

This report documents a performance evaluation of the Federal Highway Administration’s Sign Management And Retroreflectivity Tracking System (SMARTS) van. The van’s purpose is to photograph, record the location, and measure the retroreflectivity of traffic signs while traveling at highway speeds. Alaska needs a cost-effective method of inventorying signs and measuring their reflectivity to manage its $20+ million investment in signs, to know what signs are missing or illegible, and to analyze its compliance with impending national standards for signs retroreflectivity. Testing consisted of evaluating signs with the van on one rural and one urban road segment, evaluating signs on the rural road segment with a handheld sign retroreflectivity meter, and analyzing the results. The report concludes that the van’s performance was not acceptable. Multiple readings on individual signs varied widely from one run to the next, the percentage of signs captured by the operators on a single pass was unacceptably low, and van readings did not correlate with those of a handheld meter (handheld meters are considered the most accurate measuring device).

This report provides background on deep mixing for U.S. transportation projects and provides further information on design and construction aspects. This report also includes guidelines required for U.S. transportation engineers to plan, design, construct, and monitor deep mixing projects for embankment and foundation support applications. Considerations for secondary associated applications such as excavation support and liquefaction mitigation are also discussed.

This report presents the results of the Federal Highway Administration's (FHWA) Office of Operations-sponsored Focus States Initiative (FSI) designed to advance the state-of-the-practice for traffic incident management (TIM) performance measurement. Through this effort, 11 Focus States1 identified several national-level TIM program objectives and related performance measures. During the process, the States successfully overcame institutional, operational, and technical barriers and defined three multi-agency, measurable TIM objectives and methods of measuring performance toward those objectives. All 11 Focus States committed to build on the momentum generated by the TIM FSI and to continue to work together to advance program-level performance measurement in their States as well as nationwide.

This report evaluates guardrail end terminals for use in the State of Alaska which has unique winter maintenance concerns. With significant snowfall levels and cold temperatures, Alaska needed to identify an end terminal that can withstand these conditions and can be readily repaired while acknowledging the limitations of frozen grounds. The study collects product data from seven different vendors and eight northern tier state Departments of Transportation. While the study tends to focus on winter repair and replacement, the study collects general information regarding the cost and installation of the terminal as well as product quality and compatibility.

Cable barriers are longitudinal roadside devices used to contain and/or redirect errant vehicles that depart the roadways. These barriers gradually redirect or arrest an impacting vehicle by stretching the cables, minimizing forces on the vehicle and its occupants. While cable barriers have been used on U.S. highways for more than 60 years, their use has been on the rise and is expected to increase in the future. This increase in use I attributed to cable barriers’ success rate in keeping vehicles from crossing the median or leaving the roadway, reduced impact severity, availability of new cable barrier technologies, low initial installation cost, and suitability for various median and roadside environments.

The Federal Highway Administration, in support of the Traffic Analysis and Simulation Pooled Fund Study, initiated this study to identify and address consistency in the selection and use of traffic analysis tools. This report offers recommendations on the management, planning, and conduct of traffic analysis that will promote greater traffic analysis tool consistency over the typical project development life cycle. It is directed toward professionals operating in State departments of transportation and other agencies responsible for transportation project development and delivery.

In this guide, T2 refers to a way that ideas, knowledge, practices, products, processes, or techniques are shared between and within organizations. As a purposeful action, T2 involves at least two parties, a source and a recipient, engaged in the sharing of knowledge about new practices, products, processes, or other elements of technology. T2 may be initiated by the source, the recipient, mutually by both, or by a third party acting to facilitate the sharing.

This guidebook is intended to help communities develop performance measures that can fully integrate pedestrian and bicycle planning in ongoing performance management activities. It highlights a broad range of ways that walking and bicycling investments, activity, and impacts can be measured and documents how these measures relate to goals identified in a community's planning process. It discusses how the measures can be tracked and what data are required, while also identifying examples of communities that are currently using the respective measures in their planning process. This report highlights resources for developing measures to facilitate high-quality performance-based planning.