Engineering Commons^™

Evaluating The Safety Effects Of Signal Improvements, Ashley Lynn Dowell

Theses and Dissertations

As a result of high crash frequencies on roadways, transportation safety has become a high priority for the United States Department of Transportation and the Utah Department of Transportation. A large percentage of fatal and injury crashes on roadways occur at intersections and traffic signals have been implemented to reduce these severe crashes. There is a need to evaluate the effectiveness of the traffic signal improvements through the development of Crash Modification Factors (CMFs). Recent research has shown that traditional safety evaluation methods have been inadequate in developing CMFs. In recent years, Bayesian statistical methods have been utilized in traffic …

Understanding The Economics Of Transportation In Utah, Jeremy E. Searle

Theses and Dissertations

Understanding the economic impacts of transportation projects in Utah is essential for decision makers, officials, and stakeholders as they determine the best course of action for the state. Economic impacts can guide decisions of future projects and help explain past economic fluctuations. This study develops a process that can be used to identify the economic impacts of transportation projects in Utah and quantify the relationship between transportation and these impacts. Accomplishing the objectives of this study are a product of: 1) performing a comprehensive literature review, 2) collecting data and establishing analysis methods, 3) completing a statistical analysis and breakdown …

Analyzing The Effectiveness Of Safety Measures Using Bayesian Methods, Daniel J. Thurgood

Theses and Dissertations

Recent research has shown that traditional safety evaluation methods have been inadequate in accurately determining the effectiveness of roadway safety measures. In recent years, advanced statistical methods have been utilized in traffic safety studies to more accurately determine the effectiveness of roadway safety measures. These methods, particularly hierarchical Bayesian statistical techniques, have the capabilities to account for the shortcomings of traditional methods. Hierarchical Bayesian modeling is a powerful tool for expressing rich statistical models that more fully reflect a given problem than a simpler model could. This paper uses a hierarchical Bayesian model to analyze the effectiveness of two types …

Median Crossover Crashes In The Vicinity Of Interchanges On Utah Interstates, Katherine Elaine Winters

Theses and Dissertations

While not accounting for a significant proportion of overall crashes, median crossover crashes in the state of Utah do account for a significant proportion of interstate fatalities. Due to the seriousness of median crossover crashes in the state of Utah, the need exists to evaluate the impact of median crossover crashes in the state, to identify locations where median crossover crashes may be occurring at particularly high rates, and to identify methods to help mitigate these crashes. Previous research has noted that median crossover crash rates appear to increase in the vicinity of interchanges. The purpose of this research, therefore, …

A Safety Analysis Of Fatigue And Drowsy Driving In The State Of Utah, Hunter T. Young

Theses and Dissertations

Fatigue and drowsy driving in the state of Utah has been a causal factor in thousands of crashes over the years and poses a serious threat to public safety. Consequently, the purpose of this research was to evaluate the impact of drowsy driving in the state, to identify locations where fatigue and drowsy driving may be contributing factors to current crashes, and to identify methods to help mitigate these crashes. A 3-year drowsy driving crash rate spanning the years 2002 – 2004 was used to determine which segments of Utah highway are most prone to drowsy driving crashes. Drowsy driving …

A Prioritization Process For Access Management Implementation In Utah, Kordel T. Braley

Theses and Dissertations

Appropriate access management techniques can improve the safety and efficiency of arterial roads. In order to determine which roads can most benefit by the implementation of access management techniques, a prioritization process was developed to recommend various access management treatments such as limiting access points, installing raised medians, and ensuring adequate signal spacing along corridors. To serve as the basis for the performance index, a database was created including identifying features, characteristics, and crash history for 175 arterial road segments on Utah state routes. Stepwise linear regression was applied to the data collected to determine which characteristics of the roads …

Assessing The Economic Impacts Of Transportation Improvement Projects, Andrew L. Stewart

Theses and Dissertations

In that a transportation system can influence an economy for good or bad a system that enhances economic vitality becomes a crucial element in maintaining or developing economic prosperity. To provide a methodology to include economic development impacts of transportation improvement projects in the decision making process and the tools and alternatives available are here explored. Primary contributions of this document are results of a literature review, transportation professional and decision maker survey, economic modeling tool evaluation, and development of approach alternatives. The following thesis introduces the purpose and need for the given research, the procedure that was followed, the …

Coordinated Regional And City Planning Using A Genetic Algorithm, Michael B. Lowry

Theses and Dissertations

Improved methods of planning are needed to deal with today's issues of traffic congestion, sprawl, and loss of greenspace. Past research and recent legislation call for new methods that will consider a regional perspective. Regional planning is challenged with two difficult questions:

1.Is it possible to achieve regional goals without infringing upon the local autonomy of city planners?

2.Is it possible to objectively analyze the thousands, even millions, of land use and transportation plans to find the best design?

Metropolitan regions across the country have made great efforts to answer the first question. Unfortunately, effective methods for harmonizing the goals …