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Impacts of National Science Foundation Engineering Research Support on Society
by National Academies of Sciences, Engineering, and Medicine National Academy of Engineering Program Office Committee on Extraordinary Engineering Impacts on SocietyEngineering advances economic growth, enhances manufacturing capacity, enhances infrastructure resilience, improves healthcare, and strengthens national security. However, the impact of engineering research – and, by extension, engineering education – is often hidden from the public eye. Promoting comprehension of how engineering affects society is thus a crucial aspect of garnering and sustaining public backing of policies aimed at ensuring that technology continues to serve the greater good of humanity. One part of this effort is highlighting the pivotal role of federal support of engineering research. Such support furnishes researchers with the necessary resources to pursue ambitious projects, fostering exploration into fundamental questions, groundbreaking technology and engineered systems developments, and practical applications. Since its inception in 1950, the National Science Foundation (NSF)—an independent federal agency–has played a critical role in funding cutting-edge research, including in engineering. At the request of NSF, Impacts of National Science Foundation Engineering Research Support on Society explores how investment in engineering research and education has led to positive societal impacts, focusing on the stories of the people responsible for these impacts. This report presents clear, compelling narratives for the public about the sources and effects of engineering innovations and offer recommendations on how to bring this information to the attention of diverse audiences.
Guidelines for Evaluating Crashworthiness of Sign Supports and Breakaway Luminaire Poles
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Cing-Dao Steve Kan Fadi Tahan Dhafer Marzougui Mohammadreza Rajaee Riley Ruskamp Chen Fang Cody Stolle Ronald Faller Robert Bielenberg Mojdeh Asadollahi PajouhState departments of transportation employ numerous variations of luminaire and sign support systems that require evaluations for their crashworthiness. Guidelines for families of devices with similar crashworthy performance have the potential to reduce costs and promote compliance with the AASHTO Manual for Assessing Safety Hardware (MASH). NCHRP Research Report 1123: Guidelines for Evaluating Crashworthiness of Sign Supports and Breakaway Luminaire Poles, from TRB's National Cooperative Highway Research Program, presents research results and preliminary guidelines for evaluating families of devices for sign supports and breakaway poles under MASH. Supplemental to the report is NCHRP Web-Only Document 405: Evaluating Crashworthiness of Sign Supports and Breakaway Luminaire Poles: Appendices.
Active Traffic Management Strategies: A Planning and Evaluation Guide
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Maya Bouchet Lisa Burgess Srinivasa Sunkari Kevin Balke Ioannis Tsapakis Jeffrey Shelton Margaret Fowler Robert Brydia Beverly KuhnActive traffic management (ATM) is the ability to manage recurrent and nonrecurrent congestion, both dynamically and proactively, on transportation infrastructure based on real-time or predicted traffic conditions. Focusing on trip reliability, ATM strategies maximize the effectiveness and efficiency of a facility while increasing throughput and enhancing safety. NCHRP Research Report 1120: Active Traffic Management Strategies: A Planning and Evaluation Guide, from TRB's National Cooperative Highway Research Program, is designed to provide planning and evaluation guidelines to transportation agencies so they can easily identify the appropriate path forward with ATM strategies suited to their regional needs and characteristics. In addition to NCHRP Research Report 1120, an associated publication, NCHRP Web-Only Document 402: Developing a Planning and Evaluation Guide for Active Traffic Management Strategies, documents the research undertaken for the project.
Progress Toward Restoring the Everglades: The Tenth Biennial Review—2024
by National Academies of Sciences, Engineering, and Medicine Division on Earth and Life Studies Water Science and Technology Board Committee on Independent Scientific Review of Everglades Restoration ProgressThe Florida Everglades is a treasured ecosystem, but the water quality, quantity, flow, and distribution have been dramatically degraded by drainage and infrastructure development during the past century. A joint effort launched by the State and federal government in 2000, the Comprehensive Everglades Restoration Plan (CERP) seeks to reverse the decline of the ecosystem. The National Academies have provided a biennial review of CERP since 2004. This tenth biennial report in the series highlights significant recent restoration progress and offers guidance in three areas: applying Indigenous Knowledge in project planning, using modeling tools for understanding the effects of climate change on the CERP, and strengthening adaptive management for CERP decision making. Thanks to record state and federal investments in recent years, the pace of restoration implementation has reached historic levels and sizeable restoration benefits have been achieved. However, information on natural system restoration progress relative to CERP expectations continues to be difficult to find and interpret. The report recommends modeling tools be applied to anticipate the effects of climate change, including temperature and precipitation, on CERP outcomes and to inform planning and management. Moving forward, consistent and meaningful engagement between CERP agencies and tribal nations is necessary to create a partnership where Indigenous Knowledge can be considered and applied in restoration decision-making. Building expertise and a culture of adaptive management can help ensure continued restoration progress amid uncertainties and improve restoration outcomes through the incorporation of new information.
Bus Operator Barrier Design: Guidelines and Considerations
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Transit Cooperative Research Program Christy Campoll Tarah Crowder Aditi Manke Erin Mabry Joshua Skole Scott Tidwell Andrew KrumThe nation was reminded of the importance of security barriers for transit bus operators by the fatal attack on a Tampa, Florida bus operator in 2019. The need for security barriers was reinforced by a serious attack on another operator for that same system later that year. While these are two extreme examples, they are likely not unique, as many assaults against transit workers have been underreported in the past. Another important but more pernicious risk to bus operator health is viral and bacterial infection. TCRP Research Report 249: Bus Operator Barrier Design: Guidelines and Considerations, from TRB's Transit Cooperative Research Program, provides information and guidance for North American public transportation agencies, standards committees, and government and non-government policymaking organizations on designing, procuring, and installing bus operator barriers to prioritize the health and safety of essential operators and the public they serve.
Effective Low-Noise Rumble Strips
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Shannon McKenna Judith Rochat Carrie J. Janello Paul R. DonavanRumble strips are proven safety countermeasures for roadway departure crashes. They produce vibration and noise to alert drivers that they are drifting from the travel lane. Neighboring residents?contiguous to roadways with rumble strips?often complain about the noise generated by these appurtenances. This has prompted a need to simultaneously study noise mitigation and rumble strip design and application. NCHRP Research Report 1107: Effective Low-Noise Rumble Strips, from TRB’s National Cooperative Highway Research Program, proposes a rumble strip design that would minimize exterior noise on the outside of the vehicle yet generate sufficient auditory and vibratory response on the inside of the vehicle to alert the operator of a roadway lane departure. Supplemental to the report are Appendices A, B, C, D, and E and a presentation.
Minimizing Utility Issues During Construction: A Guide
by Transportation Research Board National Academies of Sciences, Engineering, and Medicine National Cooperative Highway Research Program Jesse Cooper Harshit Shukla Jenny Naranjo Cesar QuirogaRoadways intersect utility facilities above and below ground. Facilities such as water, sewer, natural gas, fiber optic, and electric lines may be impacted by highway improvement projects and often require relocation. Issues and conflicts between highway features and utility facilities can arise and impede highway construction projects, causing construction delays, economic impacts, and safety concerns. NCHRP Research Report 1110: Minimizing Utility Issues During Construction: A Guide, from TRB’s National Cooperative Highway Research Program, provides practitioners with a guide to help mitigate utility conflicts using strategies such as improving pre-letting utility investigations, inspection procedures, and change order documentation. Supplemental to the report is NCHRP Web-Only Document 396: Strategies to Address Utility Issues During Highway Construction, a presentation, and an implementation plan.
Strategies to Address Utility Issues During Highway Construction
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Jesse Cooper Harshit Shukla Jenny NaranjoWhile considerable progress has been made to address utility issues before a project goes to letting, a substantial knowledge gap remains relative to the management of utility conflicts during construction. NCHRP Web-Only Document 396: Strategies to Address Utility Issues During Highway Construction, from TRB’s National Cooperative Highway Research Program, is a supplemental document to NCHRP Research Report 1110: Minimizing Utility Issues During Construction: A Guide.
Design of Piles for Downdrag
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Aaron Budge Amalesh Jana Armin W. Stuedlein Johnathan D. Blanchard Richard A. CoffmanMany bridges are constructed in areas where there is compressible soil or liquefiable soil, which necessitates the consideration of downdrag forces and associated settlement. Downdrag for static and seismic conditions has increasingly placed greater demands on existing and new foundations and also led to higher construction costs. NCHRP Research Report 1112: Design of Piles for Downdrag presents procedures for determining downdrag loads used in the design of bridge piles. The NCHRP Research Report 1112 appendices are available as NCHRP Web-Only Document 398: Pile Design for Downdrag: Examples and Supporting Materials.
Pile Design for Downdrag: Examples and Supporting Materials
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Aaron S. Budge Amalesh Jana Armin W. Stuedlein Johnathan D. Blanchard Richard A. CoffmanNCHRP Web-Only Document 398: Pile Design for Downdrag: Examples and Supporting Materials from TRB's National Cooperative Highway Research Program, provides appendices to NCHRP Research Report 1112: Design of Piles for Downdrag.
Mental Health, Wellness, and Resilience for Transit System Workers
by National Academies of Sciences, Engineering, and Medicine Transit Cooperative Research Program Koshy Koshy Lilly Derby Soumitra S. Bhuyan Samantha G. Farris Lori Zeller Sofie Rhoads Kyle Hearing Elias Frantz Orjuela Sandy BrennanTransit agency leadership must make a real and concerted effort to take the mental health and overall wellness of frontline workers more seriously. Leadership can play an important role by making a clear commitment and dedicating resources to address mental health, wellness, and resiliency at their agencies. Ultimately, this means that more funding and staff resources are needed to address barriers and to develop, implement, and support programs aimed at improving mental health, wellness, and resiliency. This includes staff dedicated to implementing and monitoring holistic wellness programs. TCRP Research Report 245: Mental Health, Wellness, and Resilience for Transit System Workers, from TRB’s Transit Cooperative Research Program, provides a detailed summary of common factors that influence the mental health, well-being, and resiliency of frontline transit workers and includes a range of solutions that transit agencies can implement to address them. Findings were determined using a mix of research methods, including multiple interviews and focus groups with frontline employees, transit agency management, and union leadership at two different points in the project. Supplemental to the report are a research brief and an implementation plan.
Transit Agencies Providing or Subsidizing Innovative Micromobility Projects: Legal Issues
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Transit Cooperative Research Program Matthew W. DausThe use of scooters, bicycles, e-bikes, and other forms of micromobility has accelerated due to the COVID-19 pandemic, urban congestion, and parking restrictions. Some transit agencies provide or subsidize micromobility to bridge the gap between transit stops and destinations beyond a comfortable walking distance. While bikes and scooters are not new, micromobility has only recently been used in public transit. TCRP Legal Research Digest 61: Transit Agencies Providing or Subsidizing Innovative Micromobility Projects: Legal Issues, from TRB's Transit Cooperative Research Program, presents practices for transit agencies to consider when implementing shared-use micromobility systems to provide and support public transit, including accessibility, safety, regulation, jurisdiction, service quality, theft, insurance, liability, security, tracking, licensing, permitting, franchising, billing, maintenance, environmental justice, and compliance with civil rights laws. It also provides examples of cities regulating bike and scooter share programs and transit agencies participating in such programs.
Creating Self-Directed Resiliency Plans for General Aviation Airports
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Airport Cooperative Research Program Mia Held Kim Fabend Mia Stephens Bridget Smith Lavanya Desai Alexis Lollar Amanda WittThere are nearly 3,000 general aviation (GA) airports that are important to the communities in which they operate and are key contributors to the successful network of the national airport system. GA airports are uniquely positioned assets in any community, and it is therefore essential for GA staff to understand, predict, and address shocks (such as airplane accidents, severe weather, and utility outages) and stressors (such as employment challenges, aging infrastructure, and climate change impacts) before they happen. ACRP Research Report 263: Creating Self-Directed Resiliency Plans for General Aviation Airports, from TRB’s Airport Cooperative Research Program, is a guide and toolkit that prepares GA airports to respond to, adapt to, and recover from all varieties of stressors and shocks while maintaining operations. Supplemental to the report are a flyer, an overview PowerPoint, and a set of associated tools and templates.
Implementing Machine Learning at State Departments of Transportation: A Guide
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Kaan Ozbay Kelly Bare Sherif Ishak Mecit Cetin Matthew Samach Haley TownsendWithin the last two decades, Machine Learning (ML), the main subfield of Artificial Intelligence (AI), has gained significant momentum across all sectors, driven by a confluence of factors: exponential growth in data generation, advancements in data storage and computing, and innovations in algorithmic techniques. Most notably and recently, the proliferation of deep learning (DL) methods and generative AI tools (GATs) such as ChatGPT are revolutionizing the business landscape. In an era where data is pouring in from new sources, the pace of data growth is exceeding the pace at which state and local Departments of Transportation (DOTs) are able to use it. NCHRP Research Report 1122: Implementing Machine Learning at State Departments of Transportation: A Guide, from TRB's National Cooperative Highway Research Program, serves as both an education and a decision-making tool to assist state DOTs and other transportation agencies in identifying promising ML applications; assessing costs, benefits, risks, and limitations of different approaches; and building a data-driven organization conducive to capitalizing on and expanding ML capabilities in a broad spectrum of transportation applications. Along with supplemental files, there is an associated publication, NCHRP Web-Only Document 404: Implementing and Leveraging Machine Learning at State Departments of Transportation, which documents the overall research effort.
Uncrewed Aerial Systems Applications for Bridge Inspections: Element-Level Bridge Data Collection
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Jeffrey Sams John Zuleger Ryan Stevens Matthew Hebdon Alicia McConnellInterest in and use of uncrewed aerial systems (UAS) have increased in the past 10 years. One application of considerable interest to transportation agencies and their private-sector partners is supplementing traditional highway bridge inspection data-collection tools. They have shown particular interest in performing safety inspections of bridge elements that are typically costly for bridge owners. By using UAS, the bridge superstructure and substructure can be assessed without requiring lanes of traffic to close or exposing inspectors to traffic. NCHRP Research Report 1114: Uncrewed Aerial Systems Applications for Bridge Inspections: Element-Level Bridge Data Collection, from TRB’s National Cooperative Highway Research Program, presents strategies for using UAS for collecting element-level data during bridge inspections. Supplemental to the report are a survey, rankings, implementation memo, and roadmap.
Visualization for Public Involvement
by Transportation Research Board National Academies of Sciences, Engineering, and Medicine National Cooperative Highway Research Program Pamela Lebeaux Robin ChristiansVisualization methods have long been integral to the public involvement process for transportation planning and project development. From well-established methods such as conceptual sketches or photo simulations to the latest immersive technologies, state departments of transportation (DOTs) recognize that visualizations can significantly increase public understanding of a project’s appearance and physical impacts. Emerging methods such as interactive three-dimensional environments, virtual reality, and augmented reality can dramatically enhance public understanding of transportation options and design concepts. NCHRP Synthesis 632: Visualization for Public Involvement, from TRB’s National Cooperative Highway Research Program, documents state DOT practices of visualization for public involvement throughout the life cycle of plans, programs, and projects.
Examination of Transit Agency Coordination with Electric Utilities
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Transit Cooperative Research Program Lisa JerramPublic transit agencies across the United States are transitioning conventional bus fleets to battery electric buses (BEBs). This transition requires large investments in charging infrastructure as well as new demands on the power grid, which provides opportunities for partnership with electric utilities to upgrade grid supply and energy loads, and also to reduce costs during peak load. TCRP Synthesis 175: Examination of Transit Agency Coordination with Electric Utilities, from TRB’s Transit Cooperative Research Program, provides practitioners and operational staff at public transit bus agencies and electric utilities with the state of current practices by agencies and utilities that are collaborating on BEB planning and deployments.
Understanding Airport Air Quality and Public Health Studies Related to Airports, Second Edition
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Airport Cooperative Research Program Margaret Zenke Cory Cook Lige Han Charlotte O’Donnell Maureen MullenThe communities surrounding airports have become increasingly aware of airport emissions and potential impacts of those emissions on local air quality and public health. Those concerns along with growth in airport operations have spurred the need for airport operators to more fully understand the potential for health impacts related to airport operations and to develop better information and methods to share this information with the public. ACRP Web-Only Document 62: Understanding Airport Air Quality and Public Health Studies Related to Airports, Second Edition, from TRB’s Airport Cooperative Research Program, evaluates and updates the existing body of knowledge on air quality and public health studies related to airports to help airport operators better understand and respond to airport-related air quality and public health concerns. Supplement to the document is an interactive version of Appendix A from the report that lists relevant peer-reviewed publications.
Law Enforcement Use of Probabilistic Genotyping, Forensic DNA Phenotyping, and Forensic Investigative Genetic Genealogy Technologies: Proceedings of a Workshop
by National Academies of Sciences, Engineering, and Medicine Division on Engineering and Physical Sciences Division of Behavioral and Social Sciences and Education Computer Science and Telecommunications Board Committee on Law and JusticeTo better understand key considerations around law enforcement use of advanced forensic DNA technologies, the Committee on Law and Justice and the Computer Science and Telecommunications Board at the National Academies of Sciences, Engineering, and Medicine held a workshop titled "Law Enforcement Use of Probabilistic Genotyping, Forensic DNA Phenotyping, and Forensic Investigative Genetic Genealogy Technologies." The workshop was organized in response to Executive Order 14074, issued in May 2022, and was held on March 13 and 14, 2024. The order focused on advancing effective, accountable policing, as well as criminal justice practices around algorithmic approaches to policing; it directed the National Academies to hold a workshop to explore the different approaches. The workshop focused on three specific advanced forensic DNA practices: probabilistic genotyping, forensic DNA phenotyping, and forensic investigative genetic genealogy. This publication summarizes the presentations and discussion of the workshop.
Considering Greenhouse Gas Emissions and Climate Change in Environmental Reviews: Conduct of Research Report
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Zamurs and Associates, LLC Inch And Meter Parametrix Georgetown Climate CenterMany state departments of transportation (DOTs) are working to incorporate the treatment of greenhouse gas (GHG) emissions, climate change effects, or both in project planning and environmental reviews. There is a wide range of experience, with some states working hard to integrate all of their activities (including environmental review) into a unified, agency-wide treatment of climate change while others are just beginning their efforts. NCHRP Web-Only Document 400: Considering Greenhouse Gas Emissions and Climate Change in Environmental Reviews: Conduct of Research Report supplements the resources and guidance for state DOTs on addressing climate change effects and GHG emissions provided by NCHRP WebResource 3: GHG Emissions and Climate Change in Environmental Reviews. Supplemental to NCHRP Web-Only Document 400 is a fact sheet that summarizes the essential findings of the project and provides an overview of the WebResource, as well as an implementation memo that identifies implementation pathways for the project.
Planning for Future Electric Vehicle Growth at Airports
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board Airport Cooperative Research Program Sara Kaplan Angela Archibeque Krista Robertson Maranda Thompson Kate Andrus Mia Stephens Grant Bennett Rex HazeltonBecause of the diversity of charging needs at airports and the varied policy environments in which airports operate, no single roadmap describes how to best install electric vehicle charging. Furthermore, an airport may use multiple approaches to owning and operating charging infrastructure. To help simplify this complex space, this planning guide categorizes charging into eight use cases. ACRP Web-Only Document 61: Planning for Future Electric Vehicle Growth at Airports, from TRB’s Airport Cooperative Research Program, is designed as a primer to help educate airport staff and practitioners on the technologies and processes associated with charging infrastructure. The guide was developed in Phase I of a project that will include additional products in Phase II.
Diagnostic Assessment and Countermeasure Selection: A Toolbox for Traffic Safety Practitioners
by John L. Campbell Transportation Research Board National Academies of Sciences, Engineering, and Medicine National Cooperative Highway Research Program Behavioral Traffic Safety Cooperative Research Program Ingrid B. Potts Darren J. Torbic Audra K. Fraser Chris Monk Liberty Hoekstra-AtwoodSuccessful safety management practices require a thorough understanding of factors contributing to motor vehicle crashes. Continuous advancements in data-driven safety analysis, as well as the countermeasures and technologies available to address crashes, create challenges in maintaining a safety workforce proficient in the state of the practice. In many cases, agencies continue to use approaches such as descriptive statistics and anecdotal information to perform the diagnostic assessment without a thorough understanding of the expectations for a given context or road type. NCHRP Research Report 1111/BTSCRP Research Report 12: Diagnostic Assessment and Countermeasure Selection: A Toolbox for Traffic Safety Practitioners, from TRB's National Cooperative Highway Research Program and Behavioral Traffic Safety Cooperative Research Program, presents a toolbox to help highway safety practitioners diagnose contributing factors leading to crashes for use in selecting appropriate countermeasures. Supplemental to the report are a Conduct of Research Report, an Implementation of Findings, and a presentation.
Resolving Construction Disputes: Review of State DOT Processes
by National Academies of Sciences, Engineering, and Medicine Transportation Research Board National Cooperative Highway Research Program Michael C. LoulakisCommercial disputes among owners, contractors, and subcontractors on construction projects are a fact of life, regardless of how hard parties might try to avoid them. Sometimes these disputes get resolved quickly at the project level, but sometimes the dispute is handled through litigation. NCHRP Legal Research Digest 92: Resolving Construction Disputes: Review of State DOT Processes, from TRB's National Cooperative Highway Research Program, aims to build a better understanding of what state departments of transportation (DOTs) are doing in terms of alternative dispute resolution (ADR) processes and reviews state DOT practices for construction disputes.
Pay and Working Conditions in the Long-Distance Truck and Bus Industries: Assessing for Effects on Driver Safety and Retention
by National Academies of Sciences, Engineering, and Medicine Division of Behavioral and Social Sciences and Education Transportation Research Board Committee on National Statistics Consensus and Advisory Studies Committee for a Study of the Impacts of Alternative Compensation Methods on Truck Driver Retention and Safety PerformanceFor-hire trucking—as opposed to in-house private carriers that transport the goods of their parent company—is a large and heterogeneous industry with considerable variability in carrier sizes, operational structures, and freight markets served. For this sector, the Federal Motor Carrier Safety Administration should explore opportunities for leveraging research and data collection that may be planned and programmed for other purposes to help regulators, researchers, and industry examine the potential effects of driver compensation and work conditions on the safe driving behavior and performance of long-distance for-hire truck drivers. This is among the recommendations in TRB Special Report 355: Pay and Work Conditions in the Long-Distance Truck and Bus Industries: Assessing for Effects on Driver Safety and Retention, from the Transportation Research Board of the National Academies of Sciences, Engineering, and Medicine. The report examines—in response to a request from the U.S. Congress—the impacts of various methods of driver compensation on safety and driver retention, including hourly pay, payment for detention time, and other payment methods used in the industry.
Bridge Railing Design Requirements
by Transportation Research Board Thomas P. Murphy National Cooperative Highway Research Program Mark Bloschock Marcus Galvan Ronald K. Faller Andrew E. Loken Scott K. Rosenbaugh Joshua S. Steelman Maria D. Lopez John M. HoltAs of January 1, 2020, all new and replacement bridge rails installed on the National Highway System are required to conform to the requirements stipulated in the AASHTO Manual for Assessing Safety Hardware [MASH], 2nd edition (2016). NCHRP Research Report 1109: Bridge Railing Design Requirements, from TRB's National Cooperative Highway Research Program, presents an update to bridge railing design requirements to ensure consistency with the state of knowledge. The update incorporates the recommendations from NCHRP Research Report 1024: Evaluation of Bridge Rail Systems to Confirm AASHTO MASH Compliance and NCHRP Research Report 1078: MASH Railing Load Requirements for Bridge Deck Overhang. An appendix to the report presents design examples for railings and deck overhangs.