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- All Subjects: Civil Engineering
- All Subjects: Urban Heat Islands
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Description
Concrete stands at the forefront of the construction industry as one of the most useful building materials. Economic and efficient improvements in concrete strengthening and manufacturing are widely sought to continuously improve the performance of the material. Fiber reinforcement is a significant technique in strengthening precast concrete, but manufacturing limitations are common which has led to reliance on steel reinforcement. Two-dimensional textile reinforcement has emerged as a strong and efficient alternative to both fiber and steel reinforced concrete with pultrusion manufacturing shown as one of the most effective methods of precasting concrete. The intention of this thesis project is to detail the components, functions, and outcomes shown in the development of an automated pultrusion system for manufacturing textile reinforced concrete (TRC). Using a preexisting, manual pultrusion system and current-day manufacturing techniques as a basis, the automated pultrusion system was designed as a series of five stations that centered on textile impregnation, system driving, and final pressing. The system was then constructed in the Arizona State University Structures Lab over the course of the spring and summer of 2015. After fabricating each station, a computer VI was coded in LabVIEW software to automatically drive the system. Upon completing construction of the system, plate and angled structural sections were then manufactured to verify the adequacy of the technique. Pultruded TRC plates were tested in tension and flexure while full-scale structural sections were tested in tension and compression. Ultimately, the automated pultrusion system was successful in establishing an efficient and consistent manufacturing process for continuous TRC sections.
ContributorsBauchmoyer, Jacob Macgregor (Author) / Mobasher, Barzin (Thesis director) / Neithalath, Narayanan (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / The Design School (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
It is the intent of this research to determine the feasibility of utilizing industrial byproducts in cementitious systems in lieu of Portland Cement to reduce global CO2 emissions. Class C and Class F Fly Ash (CFA and FFA, respectively) derived from industrial coal combustion were selected as the replacement materials for this study. Sodium sulfate and calcium oxide were used as activators. In Part 1 of this study, focus was placed on high volume replacement of OPC using sodium sulfate as the activator. Despite improvements in heat generation for both CFA and FFA systems in the presence of sulfate, sodium sulfate was found to have adverse effects on the compressive strength of CFA mortars. In the CFA mixes, strength improved significantly with sulfate addition, but began to decrease in strength around 14 days due to expansive ettringite formation. Conversely, the addition of sulfate led to improved strength for FFA mixes such that the 28 day strength was comparable to that of the CFA mixes with no observable strength loss. Maximum compressive strengths achieved for the high volume replacement mixes was around 40 MPa, which is considerably lower than the baseline OPC mix used for comparison. In Part 2 of the study, temperature dependency and calcium oxide addition were studied for sodium sulfate activated systems composed of 100% Class F fly ash. In the presence of sulfate, added calcium increased reactivity and compressive strength at early ages, particularly at elevated temperatures. It is believed that sulfate and calcium react with alumina from fly ash to form ettringite, while heat overcomes the activation energy barrier of fly ash. The greatest strengths were obtained for mixes containing the maximum allowed quantity of calcium oxide (5%) and sodium sulfate (3%), and were around 12 MPa. This is a very low compressive strength relative to OPC and would therefore be an inadequate substitute for OPC needs.
ContributorsTweedley, Shannon Elizabeth (Author) / Neithalath, Narayanan (Thesis director) / Mamlouk, Michael (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor) / School of Sustainable Engineering and the Built Environment (Contributor)
Created2014-05
Description
The School of Sustainable Engineering and the Built Environment (SSEBE) used to have a shake table where FSE 100 professors would use students' model structures to demonstrate how failure occurs during an earthquake. The SSEBE has wanted to build a shake table ever since the original table was no longer available to them. My creative project is to design and build a shake table for FSE 100 use. This paper will go through the steps I took to design and construct my shake table as well as suggestions to anyone else who would want to build a shake table. The design of the shake table that was constructed was modeled after Quanser's Shake Table II. The pieces from the shake table were purchased from McMaster-Carr and was assembled at the TechShop in Chandler, Arizona. An educational component was added to this project to go along with the shake table. The project will be for the use of a FSE 100 classes. This project is very similar to the American Society of Civil Engineers, Pacific Southwest Conference's seismic competition. The main difference is that FSE 100 students will not be making a thirty story model but only a five story model. This shake table will make Arizona State University's engineering program competitive with other top universities that use and implement shake table analysis in their civil engineering courses.
ContributorsLockhart, Laura E. (Author) / Ward, Kristen (Thesis director) / Hjelmstad, Keith (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The growing urban heat island (UHI) phenomenon is having detrimental effects on urban populations and the environment, and therefore, must be addressed. The purpose of this research is to investigate possible strategies that could be utilized to reduce the effects of the urban heat island for the city of Phoenix. Current strategies, case studies, and the ENVI-Met modeling software were used to finalize conclusions and suggestions to further progress Phoenix's goals in combating its urban heat island. Results from the studies found that there is much potential in reducing daytime and evening temperatures through improving infrastructure by means of increased vegetation in the forms of green roofs and walls, reducing anthropogenic heat release, improving artificial surface coverage, and implementing lasting policies for further development. Results from the ENVI-met microclimate program shows areas for further research in urban heat island mitigation strategies.
ContributorsShqalsi, Ema (Author) / Pijawka, David (Thesis director) / Middel, Ariane (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
As inhabitants of a desert, a sustainable water source has always been and will continue to be a crucial component in developing the cities Arizonans call home. Phoenix and the surrounding municipalities make up a large metropolitan area that continues to grow in spatial size and population. However, as climate change becomes more of an evident challenge, Arizona is forced to plan and make decisions regarding its ability to safely and efficiently maintain its livelihood and/or growth. With the effects of climate change in mind, Arizona will need to continue to innovatively and proactively address issues of water management and the effects of urban heat island (UHI). The objective of this thesis was to study the socioeconomic impacts of four extreme scenarios of the future Phoenix metropolitan area. Each of the scenarios showcased a different hypothetical extreme and uniquely impacted factors related to water management and UHI. The four scenarios were a green city, desert city, expanded city into desert land, and expanded city into agricultural land. These four scenarios were designed to emphasize different aspects of the urban water-energy-population nexus, as the future of the Phoenix metropolitan area is dynamic. Primarily, the Green City and Desert City served as contrasting viewpoints on UHI and water sustainability. The Expanded Cities showed the influence of population growth and land use on water sustainability. The socioeconomic impacts of the four scenarios were then analyzed. The quantitative data of the report was completed using the online user interface of WaterSim 5.0 (a program created by the Decision Center for a Desert City (DCDC) at Arizona State University). The different scenarios were modeled in the program by adjusting various demand and supply oriented factors. The qualitative portion as well as additional quantitative data was acquired through an extensive literature review. It was found that changing land use has direct water use implications; agricultural land overtaken for municipal uses can sustain a population for longer. Though, removing agricultural lands has both social and economic implications, and can actually cause the elimination of an emergency source. Moreover, it was found that outdoor water use and reclaimed wastewater can impact water sustainability. Practices that decrease outdoor water use and increase wastewater reclamation are currently occurring; however, these practices could be augmented. Both practices require changes in the publics' opinions on water use, nevertheless, the technology and policy exists and can be intensified to become more water sustainable. While the scenarios studied were hypothetical cases of the future of the Phoenix metropolitan area, they identified important circumscribing measures and practices that influence the Valley's water resources.
ContributorsVon Gnechten, Rachel Marie (Author) / Wang, Zhihua (Thesis director) / White, Dave (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12