Matching Items (172)
Description
This dissertation details an attempt to experimentally evaluate the Giroud et al. (1995) concentration factors for geomembranes loaded in tension perpendicular to a seam by laboratory measurement. Field observations of the performance of geomembrane liner systems indicates that tears occur at average strains well below the yield criteria. These observations have been attributed, in part, to localized strain concentrations in the geomembrane loaded in tension in a direction perpendicular to the seam. Giroud et al. (1995) has presented theoretical strain concentration factors for geomembrane seams loaded in tension when the seam is perpendicular to the applied tensile strain. However, these factors have never been verified. This dissertation was prepared in fulfillment of the requirements for graduation from Barrett, the Honors College at Arizona State University. The work described herein was sponsored by the National Science Foundation as a part of a larger research project entitled "NEESR: Performance Based Design of Geomembrane Liner Systems Subject to Extreme Loading." The work is motivated by geomembrane tears observed at the Chiquita Canyon landfill following the 1994 Northridge earthquake. Numerical analysis of the strains in the Chiquita Canyon landfill liner induced by the earthquake indicated that the tensile strains, were well below the yield strain of the geomembrane material. In order to explain why the membrane did fail, strain concentration factors due to bending at seams perpendicular to the load in the model proposed by Giroud et al. (1995) had to be applied to the geomembrane (Arab, 2011). Due to the localized nature of seam strain concentrations, digital image correlation (DIC) was used. The high resolution attained with DIC had a sufficient resolution to capture the localized strain concentrations. High density polyethylene (HDPE) geomembrane samples prepared by a leading geomembrane manufacturer were used in the testing described herein. The samples included both extrusion fillet and dual hot wedge fusion seams. The samples were loaded in tension in a standard triaxial test apparatus. to the seams in the samples including both extrusion fillet and dual hot wedge seams. DIC was used to capture the deformation field and strain fields were subsequently created by computer analysis.
ContributorsAndresen, Jake Austin (Author) / Kavazanjian, Edward (Thesis director) / Gutierrez, Angel (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
As the demand for natural resources increases with population growth, importance has been placed on environmental issues due to increasing pressure on land, water, air, and raw materials. In order to sustain the environment and natural resources, sustainable engineering and earth systems engineering and management (ESEM) is vital for future populations. The Aral Sea and the Florida Everglades are both regions that are heavily impacted by human design decisions. Comparing and analyzing the implications and outcomes of these human design decisions allows conclusions to be made regarding how earth systems engineering and management can be best accomplished. The Aral Sea, located in central Asia between Kazakhstan and Uzbekistan, is a case study of an ecosystem that has collapsed under the pressure of agricultural expansion. This has caused extensive economic, health, agricultural, and environmental impacts. The Everglades in southern Florida is a case study where the ecosystem has evolved from its original state, rather than collapsed, due to human settlement and water resource demand. In order to determine effective sustainable engineering approaches, the case studies will be evaluated using ESEM principles. These principles are used as guidance in executing better practice of sustainable engineering. When comparing the two case studies, it appears that the Everglades is an adequate representation of effective ESEM approaches, while the Aral Sea is not reflective of effective approaches. When practicing ESEM, it is critical that the principles be applied as a whole rather than individually. While the ESEM principles do not guarantee success, they offer an effective guide to dealing with the complexity and uncertainty in many of today's systems.
ContributorsRidley, Brooke Nicole (Author) / Allenby, Brad (Thesis director) / Parrish, Kristen (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
Popular culture has a longstanding tendency for being affected by, and reversely affecting, politics. Films, in particular, can exist as either purse “escapism” or heady pathways for political commentary. During the Second World War, governments in both the United States and Great Britain used film as a vessel for their own messages, but after the war ended, the two nations allowed their respective film industries more free expression in commenting on wartime and post-war politics. Film also provided particularly vivid political commentary during, and in the years immediately following, the Cold War. Though film has a longstanding history of being a force for political commentary, the medium’s specific engagement with the Cold War holds particular significance because works produced by the two nations’ film industries paralleled the social trend toward political activism at the time. While films produced in the UK and the United States in the 1960s addressed a wide range of contentious political issues, a huge body of work was spurred on by one of the most pressing political tensions of the time: namely, the Cold War.
The United States and Great Britain were major, allied forces during the Cold War. Despite their allied positions, they had unique politico-social perspectives that greatly reflected their immediate involvement in the conflict, in addition to their respective political histories and engagement in previous wars. As the Cold War threat was a large and, in many ways, incomprehensible one, each country took certain elements of the Cold War situation and used those elements to reflect their varied political social positions to a more popular audience and the culture it consumed.
In turn, filmmakers in both countries used their mediums to make overarching political commentaries on the Cold War situation. This analysis looks at five films from those countries during the 1960s, and explores how each representation offered different, often conflicting, perspectives on how to “manage” Cold War tensions, while simultaneously reflecting their conflicted culture and political decisions. The films analyzed reveal that each country focused on contrasting perceptions about the source of the threat posed by Soviet forces, thus becoming tools to further promote their distinct political stances. While the specifics of that commentary changed with each filmmaker, they generally paralleled each country’s perspective on the overall Cold War atmosphere. The British message represented the Cold War as a very internal battle—one that involved the threat within UK borders via the infiltration of spies the tools of espionage. In contrast, the American films suggest that the Cold War threat was largely an internal one, a struggle best combatted by increasing weaponry that would help control the threat before it reached American borders.
The United States and Great Britain were major, allied forces during the Cold War. Despite their allied positions, they had unique politico-social perspectives that greatly reflected their immediate involvement in the conflict, in addition to their respective political histories and engagement in previous wars. As the Cold War threat was a large and, in many ways, incomprehensible one, each country took certain elements of the Cold War situation and used those elements to reflect their varied political social positions to a more popular audience and the culture it consumed.
In turn, filmmakers in both countries used their mediums to make overarching political commentaries on the Cold War situation. This analysis looks at five films from those countries during the 1960s, and explores how each representation offered different, often conflicting, perspectives on how to “manage” Cold War tensions, while simultaneously reflecting their conflicted culture and political decisions. The films analyzed reveal that each country focused on contrasting perceptions about the source of the threat posed by Soviet forces, thus becoming tools to further promote their distinct political stances. While the specifics of that commentary changed with each filmmaker, they generally paralleled each country’s perspective on the overall Cold War atmosphere. The British message represented the Cold War as a very internal battle—one that involved the threat within UK borders via the infiltration of spies the tools of espionage. In contrast, the American films suggest that the Cold War threat was largely an internal one, a struggle best combatted by increasing weaponry that would help control the threat before it reached American borders.
ContributorsNelson, Taylor Lynn (Author) / Miller, April (Thesis director) / O'Flaherty, Katherine (Committee member) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This dissertation investigates the potential for stimulating ureolytic and denitrifying microbes concurrently (i.e., stimulating a ureolytic, denitrifying microbial community) for a more efficient microbially induced carbonate precipitation (MICP) process. Three sand columns were run for a treatment period of six weeks with a continuous flow of nutrient solution containing calcium nitrate, calcium acetate, calcium chloride, magnesium sulfate, tryptic soy broth and trace metals. The first and third columns served as control columns, within which only denitrification processes were at work. The first column was used for periodic sampling to measure the pH, ion concentrations, and total nitrogen over time. The third column was used to measure compressional (P-) and shear (S-) wave velocities to monitor cementation and desaturation over time. The second column was subject to initial conditions identical to the other two columns except that urea was added to the nutrient solution to stimulate ureolysis and was also subject to sampling. This was done to determine whether the use of the combined MICP processes resulted in increased efficiency of precipitation. Results from ion chromatography analysis, acid digestion and scanning electron microscope imaging did not show an increase in the amount of carbonate precipitated for the second column, possibly due to nitrite inhibition and abiotic hydrolysis of the urea from sterilization of the nutrient solution through autoclaving. However, the stimulation of denitrification and ureolysis in combination was achieved, and the amount of carbonate precipitation per mol of nitrate reduced increased, which in a sense increased the efficiency of the system. Ultimately, more experimentation is needed to determine if this combination is beneficial for MICP.
ContributorsOchsenbein, Amelia Dell (Author) / Kavazanjian, Edward (Thesis director) / O'Donnell, Sean (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Recurring incidents between pedestrians, bicycles, and vehicles at the intersection of Rural Road and Spence Avenue led to a team of students conducting their own investigation into the current conditions and analyzing a handful of alternatives. An extension of an industry-standard technique was used to build a control case which alternatives would be compared to. Four alternatives were identified, and the two that could be modeled in simulation software were both found to be technically feasible in the preliminary analysis.
ContributorsFellows, Christopher Lee (Author) / Lou, Yingyan (Thesis director) / Zhou, Xuesong (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The storm events of summer 2014 proved to be some of the highest on record for Maricopa County. Flash flooding has been an ongoing issue within Arizona during the monsoon season due to the remnants of hurricanes that result in short, high intensity storms. The proximity of these intense storm events and their corresponding flooding structures is imperative in reducing the impact of these events on the community. The analysis of the maximum precipitation events for Tempe, Scottsdale, Phoenix, Mesa, Chandler, Goodyear, Peoria, Avondale and Glendale during the summer of 2014 proved that there were many events that had a calculated recurrence of 100 years or greater. The storm event with the most precipitation events with a recurrence of 100 years or greater was September 8, 2014. This storm event also produced a streamflow response that had the highest recorded streamflow at gages near the events with a 100 year recurrence. These intervals represent a larger amount of rain during a precipitation event and this correlation suggests that short burst of extreme weather was not a trend in this data. Rather, high storm events occurred over the span of 24 hours. The most frequent response of the stream gage to this rain event was a streamflow event that has a recurrence of 2-5 years. This suggests that the channels and flooding structures used to contain the rain events were effective in reducing the amount of water and therefore effectively managing the flooding response. An analysis of newspaper commentary and an interview with a representative from the Flood Control District of Maricopa County (FCDMC) indicated that there is a disconnect between public perception and the structure of FCDMC. Through this analysis a better understanding of the FCDMC as well as the impact of severe storm events in Maricopa County was found.
ContributorsBrancati, Olivia Anne (Author) / Vivoni, Enrique (Thesis director) / White, Dave (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Accidental wetlands have been created on the bed of the Salt River and are fed by storm-water outfalls discharging at various sections of the Phoenix Metropolitan Area. Water discharges from these outfalls throughout the year, during both dry conditions (base flow) and during rain events (storm flow). In this study, DOC content and composition was studied during these two flow conditions, in the outfalls and along the wetland flow path. The importance of DOC lies in its role in transporting carbon via water movement, between different parts of a landscape, and therefore between pools in the ecosystem. Urbanization has influenced content and composition of DOC entering the accidental urban wetland via outfalls as they represent watersheds from different areas in Phoenix. First, DOC load exhibited higher quantities during stormflow compared to baseflow conditions. Second, DOC load and fluorescence analysis outcomes concluded the outfalls are different from each other. The inputs of water on the north side of the channel represent City of Phoenix watersheds were similar to each other and had high DOC load. The northern outfalls are both different in load and composition from the outfall pipe on the southern bank of the wetland as it represents South Mountain watershed. Fluorescence analysis results also concluded compositional changes occurred along the wetland flow path during both stormflow and baseflow conditions. In this study, it was explored how urbanization and the associated changes in hydrology and geomorphology have affected a desert wetland's carbon content.
ContributorsBone, Stephanie Rosalia (Author) / Hartnett, Hilairy (Thesis director) / Palta, Monica (Committee member) / Mascaro, Giuseppe (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Teaching methods in the present day are beginning to transition from the traditional lecture style to the flipped learning style. The flipped classroom, also known as an engaged learning classroom, follows the model where students are presented with lecture material prior to attending class. Instead of being lectured in class, they work on applications of the material with the help of their peers and the instructional staff. One component that many engaged learning environments have in common is lecture videos for the students to view prior to attending class. An undergraduate civil engineering course at Arizona State University is modeled using an engaged learning environment; however, it does not provide lecture videos for the students. Many students in this course are seeing an engaged learning environment for the first time and need guidance on how to prepare for the course, how to approach course material, and how to interpret feedback, in addition to getting help in the technical concepts. This project aims to create supplemental lecture videos based on the concepts that students in the class identified as needing more information, as well as topics that will help students make this transition to an engaged learning environment. A series of sixteen videos were created and posted for the students to view prior to attending recitation periods. The feedback from the students regarding the videos was studied and implementation techniques for future semesters were tested.
ContributorsFlys, Victoria Pilar (Author) / Hjelmstad, Keith (Thesis director) / Baisley, Amie (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
This paper features analysis of interdisciplinary collaboration, based on the results from the Kolbe A™ Index of students in the Nano Ethics at Play (NEAP) class, a four week course in Spring 2015. The Kolbe A™ is a system which describes the Conative Strengths of each student, or their natural drive and instinct. NEAP utilized the LEGO® SERIOUS PLAY® (LSP) method, which uses abstract LEGO models to describe answers to a proposed question in school or work environments. The models could be described piece by piece to provide clear explanations without allowing disciplinary jargon, which is why the class contained students from eleven different majors (Engineering (Civil, Biomedical, & Electrical), Business (Marketing & Supply Chain Management), Architectural Studies, Sustainability, Anthropology, Communications, Philosophy, & Psychology).
The proposed hypotheses was based on the four different Kolbe A™ strengths, or Action Modes: Fact Finder, Follow Through, Quick Start, and Implementor. Hypotheses were made about class participation and official class twitter use, using #ASUsp, for each Kolbe type. The results proved these hypotheses incorrect, indicating a lack of correlation between Kolbe A™ types and playing. The report also includes qualitative results such as Twitter Keywords and a Sentiment calculation for each week of the course. The class had many positive outcomes, including growth in the ability to collaborate by students, further understanding of how to integrate Twitter use into the classroom, and more knowledge about the effectiveness of LSP.
The proposed hypotheses was based on the four different Kolbe A™ strengths, or Action Modes: Fact Finder, Follow Through, Quick Start, and Implementor. Hypotheses were made about class participation and official class twitter use, using #ASUsp, for each Kolbe type. The results proved these hypotheses incorrect, indicating a lack of correlation between Kolbe A™ types and playing. The report also includes qualitative results such as Twitter Keywords and a Sentiment calculation for each week of the course. The class had many positive outcomes, including growth in the ability to collaborate by students, further understanding of how to integrate Twitter use into the classroom, and more knowledge about the effectiveness of LSP.
ContributorsStevens, Jenna Marie (Author) / Seager, Thomas (Thesis director) / Jenses, Camilla (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Herberger Institute for Design and the Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
The current EPA regulation for total chromium in drinking water is the MCL standard of 0.1 milligrams per liter or 100 parts per billion (ppb) to avoid dermatological effects. With a toxicology study released in 2008 by the Department of Health and Human Services noting that hexavalent chromium is carcinogenic, the EPA is currently reviewing this MCL standard. During this review, the EPA provides monitoring guidance that requires quarterly sampling of surface water for hexavalent chromium. However, these samples monitor the instant in time that they were taken, and do not account for varying concentrations that are time-dependent. This research seeks to develop a method for monitoring hexavalent chromium in water. Using ion exchange technology, passive samplers were developed and installed at the Chandler Water Treatment Plant for a week-long monitoring event. Results show that passive samplers using ion exchange technology provide an accurate assessment of the average concentration of total chromium within the water treatment plant's effluent with 90.3% recovery of Cr(VI) in SIR-100 resin and 62.6% recovery in SIR-700.
ContributorsLesan, Dylan Scott (Author) / Westerhoff, Paul (Thesis director) / Supowit, Samuel (Committee member) / Bowen, Alexandra (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2014-05