Automobile transportation consumes a significant amount of non-reusable energy and emits emissions as by-products of fuel consumption. There has been much progress in the development of vehicle engine technology and alternative fuels to reduce the adverse impact of highway transportation on the environment. However, the research regarding the reduction of the adverse impact through highway design is still in its infancy. Furthermore, highway design manuals/guidebooks do not provide any information on environmentally-friendly designs. The primary objective of this research was to provide the tools and guidelines for a quantitative environmental evaluation in highway design. This research provided the results regarding the quantitative environmental impacts, by means of fuel consumption and emissions, of various highway geometric design conditions on the vertical grades as well as for horizontal and vertical crest curves that could be included in the highway design process. The researcher generated second-by-second speed profiles using the speed prediction models and non-uniform acceleration/deceleration models, and extracted the fuel consumption and emissions rates based on vehicle specific powers and speeds using recently developed motor vehicle emission simulator (MOVES). The generated speed profiles were matched with the extracted rates and aggregated during a trip on the grades and curves. In addition, the researcher conducted the environmental evaluation including a benefit-cost analysis with actual highway geometric data based on the proposed method and processes. The results demonstrated that fuel consumption and emissions could be significantly changed according to highway design conditions on grades and curves. Throughout the analyses, this research provides the guidelines and tools for environmental evaluations related to selected design features as a part of the highway development process. The provided guidelines and tools can reduce the uncertainty associated with the engineering judgment for environmentally-conscious highway design. Finally, this research shows the efficacy of environmentally-friendly design for sustainable (i.e., social, economical, and environmental) transportation.

The purpose of this study is the distribution, the emission factors, and the emission rates of the ventilation shafts of air pollutant concentration in the Hsuehshan tunnel, and analyze the correlation. The study, in the inside of Hsuehshan tunnel (the southern and the northern) and the three ventilation shafts, the real-world measure air pollutants(CO, NOx, NO, THC, NMHC and SO2) at the same time, and to analyze the concentration of air pollutants in the tunnel that is distribution of the time and spatial. In this study, the ventilation system is natural ventilation in the Hsuehshan tunnel, and the proportion of heavy vehicles in the period are less than 8%. The concentration of air pollutants in the tunnel, showing the exit higher than the entrance, the northern tunnel higher than the southern tunnel and the holidays higher than on weekdays concentration of distribution trends. The emissions and the concentration of air pollutants at the ventilation shaft No. 2 are the highest with the three shafts. All the ventilation shafts on holidays higher than weekdays were displayed on the trend of concentration distribution. The concentration of air pollutants in the tunnel are CO (12.04¡Ó1.85 ppm), THC (4.08¡Ó0.48 ppm), NMHC (2.21¡Ó0.46 ppm), NOx (1.58¡Ó0.23 ppm), NO (1.44¡Ó0.20 ppm) and SO2 (6.33¡Ó0.83 ppb). The results show that the emission factors of air pollutants in northern tunnel are higher than in southern tunnel by influence of slope. The emissions of ventilation shaft a sequence were CO, THC, and NOx. The concentrations(r¡×0.55 − 0.93) and the emission factors(r¡×0.60 − 0.96) of air pollutants are much related with traffic situation, and it shows that the air pollutants change with traffic condition. Comparison the emission factors between this study and past research in the Hsuehshan tunnel show that the air quality are becoming badly.

Thesis (Ph. D.)--Helsinki University of Technology, 2001. / Includes bibliographical references (p. 49-55). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 377-389). Available also in a digital version from Dissertation Abstracts.

Thesis (M.S.)--Florida State University, 2003. / Advisor: Renatus N. Mussa, Florida State University, Dept. of Civil Engineering. Title and description from dissertation home page (viewed Mar. 8, 2004). Includes bibliographical references.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Available via ProQuest Digital Dissertations. Title from first page of PDF file (viewed March 12, 2010). Includes bibliographical references (p. ). Also issued in print.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 328-349). Available also in a digital version from Dissertation Abstracts.

Risk assessment is an essential part of an effective transportation asset management program. The 2012 surface transportation bill, Moving Ahead for Progress in the 21st Century, requires state departments of transportation (DOTs) to establish risk- and performance-based asset management programs for the National Highway System. While the bill’s provisions include requirements only for pavement and bridge assets, they also recommend that DOTs consider other ancillary highway assets such as culverts and earth retaining structures, and hazards such as rockfalls and landslides. This research introduces an integrated risk framework with supporting algorithms to provide for the integration of ancillary assets and hazards into existing transportation asset management systems, and facilitate budget planning and resource allocation. The framework, Highway Assets Risk Management Decision-Support System (HARM-DSS), adopts a system-of systems perspective in defining and evaluating performance, and analyzing and addressing risk. The algorithms are developed using multi-criteria decision analysis (MCDA) and risk analysis methods; value functions are applied to scale performance attributes, and additive weighting to integrate multiple risk criteria. The methodology is applied at the corridor-level to analyze three different case studies using data with notable variability from New York, Minnesota and Oregon. The cases demonstrate the process for developing descriptive and visual information on multi-asset/hazard corridors, with sparse to medium data, in order to identify corridors that are vulnerable to failure, as well as exhibit high risk of failure within a transportation network. The results demonstrate that HARM-DSS can be applied across competing corridors or alternatives to produce descriptive and intuitive results that decision makers can use in budget planning and resource allocation. This research extends the risk-based thinking on transportation asset management, by moving it from a silo-ed to an integrated analytical platform that considers multiple non-homogenous assets and hazards simultaneously. It identifies data deficiencies and offers recommendations on the requisite data collection on asset inventory and condition to improve objectivity in the analytical process and confidence in the analysis results. In addition, it offers recommendations on the appropriate use of expert knowledge in supplementing existing data deficiencies in the interim. This work is potentially useful to decision makers involved in distributing resources to preserve the reliability and resiliency of transportation systems, as well as meet the existing performance- and risk-based Federal mandates for transportation asset management.

Using microsimulation software, with a focus on VISSIM, the analysis of different applications of merge concepts through delay and safety is presented in this thesis. In order to appropriately draw conclusions and usage trends of different merge concepts from the microsimulation software, early merge, late merge, and signal merge were first explored in a thorough literature review. While focusing primarily on delay, queues, and safety, this thesis essentially provides an introduction to determining the ideal merge concept on freeway work zones for varying roadway configurations, roadway conditions, and user demands, among other factors. In addition to delay and queuing analysis completed using VISSIM, the Federal Highway Administration’s Surrogate Safety Assessment Model (SSAM) was used to address the effects of implementing signal merge on rear-end and lane-change conflicts. Compiling the VISSIM microsimulation outputs and SSAM signal merge safety outputs, general conclusions and decisions were provided. While this thesis provides determinations of ideal merge concepts for a variety of cases, it is important for the next researcher to assess some of the assumptions that were made, to ensure that they would not significantly affect the results and analysis. / text

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