Browsing by Author "Costello, Seosamh B."

Now showing 1 - 4 of 4
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    Evaluation of Alternative Truck Lane Management Strategies Along a Section of I-81
    Rakha, Hesham A. (Virginia Tech. Virginia Tech Transportation Institute, 2010-05)
    I-81 is one of the top eight truck routes in the U.S. In the state of Virginia, I-81 traverses 325.51 miles from Tennessee in the south to the West Virginia border in the north and passes through 12 counties. The highway was designed for a 15 percent truck volume, however trucks now account for somewhere between 20 to 40 percent of the total traffic volume. In 2001, the Virginia Department of Transportation (VDOT) developed a list of key improvements for I-81. The improvements include: developing the corridor as a multi-modal facility, incorporating a high degree of efficiency and safety for all users, which may include the physical separation of commercial and passenger vehicles; considering transit or other higher occupancy travel in and around growing urban areas, and using Intelligent Transportation Systems (ITSs) as short-, mid-, and long-term solutions to improving transportation flow and management (VDOT 2004). In 2003, a U.S. house transportation bill included $1.5 billion in federal funding for dedicated truck lanes. According to Representative Don Young (Alaska), author of the bill and a strong proponent of truck-only lanes; Separate lanes for trucks will move freight more efficiently and make our highways significantly safer.
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    Life cycle cost analysis to identify the need for drainage renewal in maintenance of road asset: Case Studies from a New Zealand road network
    Mia, Mohammad N. U.; Henning, Theunis F. P.; Costello, Seosamh B.; McKegg, Campbell (2015-06-04)
    This paper presents life cycle cost analysis case studies of drainage improvements in pavement renewal sections. The methodology used was developed by the New Zealand Transport Agency (NZTA) and utilizes Net Present Value (NPV) and Economic Indicator (EI) as the tools for economic justification. Case studies on a number of renewal sites were conducted from a road network managed under a Performance Specified Maintenance Contract (PSMC) in New Zealand (NZ). Due to the contractual nature of a PSMC, that is a lump sum to manage the network for 10 years, the contractors are at risk of expensive maintenance and renewal costs from premature failure. Consequently, they have to be proactive in balancing investment for asset renewal, preventive and reactive maintenance on the road network. The majority of the network comprises of chipseal roads without any comprehensive drainage measures being present. The renewal sites selected for the case study range from flat rolling ground to rugged hilly terrain. There are side hills, natural streams, and bush areas beside the sites, thus making them particularly vulnerable to moisture induced failure. The outcome of the study is encouraging and indicates a positive gain in economic efficiency from the investment in drainage improvement. This study is the first step towards managing drainage on a road network in a more holistic manner, by identifying the costs and benefits of undertaking the appropriate investment.
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    Microscopic Analysis of Traffic Flow in Inclement Weather
    Rakha, Hesham A.; Krechmer, Daniel; Cordahi, Gustave; Zohdy, Ismail H.; Sadek, Shereef; Arafeh, Mohamadreza (United States. Federal Highway Administration, 2009-11)
    Weather causes a variety of impacts on the transportation system. An Oak Ridge National Laboratory study estimated the delay experienced by American drivers due to snow, ice, and fog in 1999 at 46 million hours. While severe winter storms, hurricanes, or flooding can result in major stoppages or evacuations of transportation systems and cost millions of dollars, the day-to-day weather events such as rain, fog, snow, and freezing rain can have a serious impact on the mobility and safety of the transportation system users. Despite the documented impacts of adverse weather on transportation, the linkages between inclement weather conditions and traffic flow in existing analysis tools remain tenuous. This is primarily a result of limitations on the data used in research activities. The scope of this research included use of empirical data, where available, to estimate weather impacts on three categories of sub models related to driver behavior, longitudinal vehicle motion models (acceleration, deceleration and car-following models), lane-changing models and gap acceptance models. Empirical data were used to estimate impacts of adverse weather on longitudinal and gap acceptance models but no suitable datasets were identified for lane changing models. Existing commercial microsimulation software packages were then reviewed to identify whether and how weather-related factors could be utilized in these models. The various sub models used in these packages to estimate longitudinal motion, lane-changing and gap acceptance models were evaluated. The research found that for the most part, weather-related factors could be incorporated into these models, although the techniques vary by package and by type of model. Additional empirical research is needed to provide confidence in weather-related adjustment factors, particularly as relates to ice and snow. This report concludes with some recommendations of future research related to weather and traffic flow. Additional work is proposed related to human factors and microscopic traffic modeling.
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    Task 1 Report for the National Highway Traffic Safety Administration: Identification and trade study analysis of alternative rear signaling systems
    Lee, Suzanne E.; Wierwille, Walter W.; Klauer, Charlie (United States. Federal Highway Administration, 2002-03)
    Rear-end crashes are the most frequently occurring type of collision, accounting for approximately 29% of all crashes and resulting in a substantial number of injuries and fatalities each year. Rear-end collisions in which the lead vehicle is stopped or moving very slowly prior to the crash account for the majority of these accidents. Over the years several initiatives have addressed the problem of rear-end crashes, with limited success. The most public of these ventures was the center high-mounted stop lamp (CHMSL), which was required to be present on automobiles beginning with model year 1986. The long-term effectiveness of the CHMSL has leveled off at about a 4% effectiveness in preventing rear-end crashes, which means there is still much room for improvement. The goal of this research effort is to develop and test a small number of enhanced rear-lighting concepts that have the potential to reduce the number of rear-end collisions. These are to include problems with stopped vehicles. This report encompasses the first task of the research effort. Task 1 involved investigating all previous efforts to develop enhanced rear-lighting systems, determining the causes of rear-end crashes, and developing a short list of rear-lighting alternatives to be tested in future research efforts under this project. The literature review revealed that numerous rear-lighting systems have been proposed over the past 30 years. Focus groups conducted with law enforcement officers found that the most common cause of rear-end crashes is driver inattention and distraction, with following too closely as the next most common cause. A review of several crash database analyses revealed similar results, as did a study in which drivers of striking vehicles were interviewed. The final subtask was to conduct a trade study to suggest two to three rear-lighting concepts for further study. An expert panel consisting of twelve rear-lighting experts was assembled. The trade study was conducted electronically (email) via a series of three questionnaires. This process resulted in the recommendation of three rear-lighting configurations for further refinement. Algorithms for the activation and deactivation of these systems were also developed during Task 1.