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ABC is a paradigm shift in the project planning and procurement approach where the need to minimize mobility impacts which occur due to onsite construction activities are elevated to a higher priority.

This article is adapted from a memo from the Department of Transportation and the Department of Justice about the requirement to provide curb ramps.

This publication identifies and provides design guidelines for bridge scour and stream instability countermeasures that have been implemented by various State departments of transportation (DOTs) in the United States. Countermeasure experience, selection, and design guidance are consolidated from other FHWA publications in this document to support a comprehensive analysis of scour and stream instability problems and provide a range of solutions to those problems.

This checklist is one of a series created to guide State and local highway maintenance and inspection staff in the use of innovative pavement preventive maintenance processes. The series is provided through the joint efforts of the Pavement Preservation Program of the Federal Highway Administration (FHWA), and the Foundation for Pavement Preservation (FP2).

The chip seal is constructed by spraying the asphalt emulsion onto the asphalt pavement, then spreading chips of aggregate into the emulsion, embedding the chips with pneumatic and rubbertired rollers, and finally sweeping to remove the excess chips. Sometimes, the process is repeated—a double seal, with emulsion, sprayed again and the second layer of chips added. The process seals fine cracks in the underlying pavement surface, reducing pavement deterioration by preventing water from intruding into the base and subgrade.

Reference manual for a workshop on the construction of pavement drainage systems for both rigid and flexible pavements. Includes examples of specifications used by several states. Covers permeable bases and longitudinal edge drain systems.

The purpose of this TechBrief is to help clarify the roles, responsibilities, and activities related to construction QA on DB projects. The specific topics discussed include QA, QC, and acceptance. Related topics such as independent assurance (IA), dispute resolution, personnel qualification, laboratory qualification, and warranties are also discussed. Some RFP and contract documents for DB projects have incorrectly assigned responsibility for acceptance to the design-builder, which is not in accordance with 23 CFR 637. Additionally, because the DB project delivery method is often used on large, complex, fast-paced projects, it presents some unique challenges that merit discussion.

The purpose of this TechBrief is to summarize a comprehensive investigation of current construction QA practices from both SHA and LPA perspectives undertaken in 2012 and to present recommendations from this analysis.

As a low-cost remedy to address crashes at unsignalized intersections on two-lane rural roads, the Federal Highway Administration (FHWA) developed and evaluated a treatment to reduce approach speeds by narrowing lanes using rumble strips in the median and on the right-lane edge. This narrowing was applied for about 150 ft on the major road approach of two-way stop-controlled (TWSC) intersections on high-speed rural roads. Eight experimental sites were retrofitted between 2007 and 2008 in Missouri, Kentucky, Pennsylvania, Florida, and Maryland. Following the acquisition of at least 2 years of post-implementation crash data, pre-and post-implementation crash analysis was conducted to compare the performance of the new treatments. Results showed a 32 percent reduction in total crashes and a 34 percent reduction in fatal/injury crashes.

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 article describes the different steps involved in a preventive maintenance plan, and what you can do to ensure the proper maintenance of both a vehicle and the wheelchair lift or other related equipment.

A guardrail is a longitudinal, roadside barrier system that is installed to prevent errant vehicles from impacting roadside obstacles. By redirecting a vehicle departing the roadway, a guardrail keeps it away from more serious hazards, both constructed (e.g., sign structures, culvert inlets, utility poles) and natural (e.g., trees, rock outcrop). Guardrail prevents vehicles from descending a steep roadside embankment or veering into the roadway median and oncoming traffic. In some cases, guardrail is installed for reasons other than to safeguard motorists against obstacles (e.g., road closure barricades and barriers protecting pedestrians or sensitive areas). When a vehicle impacts a guardrail, its driver and passengers encounter some risk. Guardrail does not eliminate the possibility of injuries or fatalities. A road engineer’s primary goal is to provide an adequate clear zone free of any obstacles and areas of concern. The only circumstance under which a guardrail should be installed is if it presents a lower risk to vehicles than unshielded roadside obstacles. Always consider alternatives to guardrail installation before deciding to install guardrail (e.g., removal or relocation of the obstacles). Where it is not practical to provide a full clear zone, the use of guardrail or another roadside barrier offers an attractive option as it significantly increases the safety of vehicles departing the roadway.

A guardrail is a longitudinal, roadside barrier system that is installed to prevent errant vehicles from impacting roadside obstacles. By redirecting a vehicle departing the roadway, a guardrail keeps it away from more serious hazards, both constructed (e.g., sign structures, culvert inlets, utility poles) and natural (e.g., trees, rock outcrop). Guardrail prevents vehicles from descending a steep roadside embankment or veering into the roadway median and oncoming traffic. In some cases, guardrail is installed for reasons other than to safeguard motorists against obstacles (e.g., road closure barricades and barriers protecting pedestrians or sensitive areas). When a vehicle impacts a guardrail, its driver and passengers encounter some risk. Guardrail does not eliminate the possibility of injuries or fatalities. A road engineer’s primary goal is to provide an adequate clear zone free of any obstacles and areas of concern. The only circumstance under which a guardrail should be installed is if it presents a lower risk to vehicles than unshielded roadside obstacles. Always consider alternatives to guardrail installation before deciding to install guardrail (e.g., removal or relocation of the obstacles). Where it is not practical to provide a full clear zone, the use of guardrail or another roadside barrier offers an attractive option as it significantly increases the safety of vehicles departing the roadway.

A guardrail is a longitudinal, roadside barrier system that is installed to prevent errant vehicles from impacting roadside obstacles. By redirecting a vehicle departing the roadway, a guardrail keeps it away from more serious hazards, both constructed (e.g., sign structures, culvert inlets, utility poles)and natural (e.g., trees, rock outcrops). Guardrail prevents vehicles from descending a steep roadside embankment or veering into the roadway median and oncoming traffic. In some cases, guardrail is installed for reasons other than to safeguard motorists against obstacles (e.g., road closure barricades and barriers protecting pedestrians or sensitive areas).

The purpose of this guide is to provide assistance to local officials and supervisors responsible for the maintenance and safety of rural roads. It provides a convenient reference to help address safety concerns commonly encountered in the field related to guardrails and culvert and bridge handrails.

This digest was developed from research conducted under NCHRP Project 20-65, Task 40, “Construction Management Practices for Rural Projects— An Assessment.” The Guidebook suggests construction management practices for rural projects and focuses on practical tools and techniques that apply to small rural construction professionals. The principal authors of this digest were Matthew Hallowell, Daniel Tran, and Keith Molenaar of the University of Colorado under subcontract to ICF International.

Provides guidelines to evaluate and select hydraulic modifications to existing drainage infrastructures that will help mitigate potential impacts of highway runoff on receiving waters. The guidelines are directed specifically at roadway facilities in dense urban limitations, high pollutant loadings, hydrologic flashiness, hydraulic constraints, legacy contamination, utility conflicts, and other issues.

A chip seal is a very effective thin surface treatment process used by maintenance managers to preserve existing asphalt pavements. The Kansas Department of Transportation (KDOT) 2014 Chip Seal Manual is a guide that provides guidelines, background, and general information for the design, construction, and inspection of chip seals. This manual is intended for use by KDOT field engineers, laboratory personnel, construction inspectors, and contractor estimators, supervisors, operators, and workers to provide procedures for the design of chip seals.

The NCHRP report presents prototype best management practices (BMPs) for the removal of dissolved metals in stormwater runoff. Three conceptual configurations are presented in detail: two vault system configurations for urban and rural settings, and an inlet scupper with media for bridge deck drainage systems. The report also includes standard protocols to accurately measure the levels of dissolved metals in stormwater.

This web page has links to the most recent versions of PASER surface evaluation and rating manuals. The site has links for Brick and Block, Asphalt Pavement, Concrete Pavement, Gravel Roads, Unimproved Roads, and Sealcoat.

Roadside barriers are critical safety devices as they shield motorist from what might be a more severe crash when leaving the roadway. Therefore, when damaged it is imperative it be repaired so that they can perform this function. The purpose of this guide is to provide highway and maintenance personnel with up-to-date information on how to identify systems and repair damaged W-beam guardrail. Various types of damage are described and guidance is provided on the need and procedure for appropriate repairs.