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Description
Today, we use resources faster than they can be replaced. Construction consumes more resources than any other industry and has one of the largest waste streams. Resource consumption and waste generation are expected to grow as the global population increases. The circular economy (CE) is based on the concept of a closed-loop cycle (CLC) and proposes a solution that, in theory, can eliminate the environmental impacts caused by construction and demolition (C&D) waste and increase the efficiency of resources’ use. In a CLC, building materials are reused, remanufactured, recycled, and reintegrated into other buildings (or into other sectors) without creating any waste.
Designing out waste is the core principle of the CE. Design for disassembly or design for deconstruction (DfD) is the practice of planning the future deconstruction of a building and the reuse of its materials. Concepts like DfD, CE, and product-service systems (PSS) can work together to promote CLC in the built environment. PSS are business models based on stewardship instead of ownership. CE combines DfD, PSS, materials’ durability, and materials’ reuse in multiple life cycles to promote a low-carbon, regenerative economy. CE prioritizes reuse over recycling. Dealing with resource scarcity demands us to think beyond the incremental changes from recycling waste; it demands an urgent, systemic, and radical change in the way we design, build, and procure construction materials.
This dissertation aims to answer three research questions: 1) How can researchers estimate the environmental benefits of reusing building components, 2) What variables are susceptible to affect the environmental impact assessment of reuse, and 3) What are the barriers and opportunities for DfD and materials’ reuse in the current design practice in the United States.
The first part of this study investigated how different life cycle assessment (LCA) methods (i.e., hybrid LCA and process-based LCA), assumptions (e.g., reuse rates, transportation distances, number of reuses), and LCA timelines can affect the results of a closed-loop LCA. The second part of this study built on interviews with architects in the United States to understand why DfD is not part of the current design practice in the country.
Designing out waste is the core principle of the CE. Design for disassembly or design for deconstruction (DfD) is the practice of planning the future deconstruction of a building and the reuse of its materials. Concepts like DfD, CE, and product-service systems (PSS) can work together to promote CLC in the built environment. PSS are business models based on stewardship instead of ownership. CE combines DfD, PSS, materials’ durability, and materials’ reuse in multiple life cycles to promote a low-carbon, regenerative economy. CE prioritizes reuse over recycling. Dealing with resource scarcity demands us to think beyond the incremental changes from recycling waste; it demands an urgent, systemic, and radical change in the way we design, build, and procure construction materials.
This dissertation aims to answer three research questions: 1) How can researchers estimate the environmental benefits of reusing building components, 2) What variables are susceptible to affect the environmental impact assessment of reuse, and 3) What are the barriers and opportunities for DfD and materials’ reuse in the current design practice in the United States.
The first part of this study investigated how different life cycle assessment (LCA) methods (i.e., hybrid LCA and process-based LCA), assumptions (e.g., reuse rates, transportation distances, number of reuses), and LCA timelines can affect the results of a closed-loop LCA. The second part of this study built on interviews with architects in the United States to understand why DfD is not part of the current design practice in the country.
ContributorsCruz Rios, Fernanda (Author) / Grau, David (Committee member) / Chong, Oswald (Committee member) / Parrish, Kristen (Committee member) / Arizona State University (Publisher)
Created2018
Description
Engineering education has long sought to incorporate greater diversity into engineering programs to prepare the profession to meet the engineering challenges of society. Increasing or retaining the conative diversity of engineering programs may help extend other kinds of diversity in the profession as well (Marburger, 2004). One measure of conation is the Kolbe ATM index.
Kolbe ATM is an index developed by Kathy Kolbe to measure the conative traits on an individual. The index assigns each individual a value in four categories, or Action Modes, that indicates their level of insistence on a scale of 1 to 10 in that Action Mode (Kolbe, 2004). The four Action Modes are:
• Fact Finder – handling of information or facts
• Follow Thru – need to pattern or organize
• Quick Start – management of risk or uncertainty
• Implementor – interaction with space or tangibles
The Kolbe A (TM) index assigns each individual a value that indicates their level of insistence with 1-3 representing resistant, preventing problems in a particular Action Mode; 4-6 indicating accommodation, flexibility in a particular Action Mode; and 7-10 indicating insistence in an Action Mode, initiating solutions in that Action Mode (Kolbe, 2004).
To promote retention of conative diversity, this study examines conative diversity in two engineering student populations, a predominately freshmen population at Chandler Gilbert Community College and a predominately junior population at Arizona State University. Students in both population took a survey that asked them to self-report their GPA, satisfaction with required courses in their major, Kolbe ATM conative index, and how much their conative traits help them in each of the classes on the survey. The classes in the survey included two junior level classes at ASU, Engineering Business Practices and Structural Analysis; as well as four freshmen engineering classes, Physics Lecture, Physics Lab, English Composition, and Calculus I.
This study finds that student satisfaction has no meaningful correlation with student GPA.
The study also finds that engineering programs have a dearth of resistant Fact Finders from the freshmen level on and losses resistant Follow Thrus and insistent Quick Starts as time progresses. Students whose conative indices align well with the structure of the engineering program tend to consider their conative traits helpful to them in their engineering studies. Students whose conative indices misalign with the structure of the program report that they consider their strengths less helpful to them in their engineering studies.
This study recommends further research into the relationship between satisfaction with major and conation and into perceived helpfulness of conative traits by students. Educators should continue to use Kolbe A (TM) in the classroom and perform further research on the impacts of conation on diversity in engineering programs.
Kolbe ATM is an index developed by Kathy Kolbe to measure the conative traits on an individual. The index assigns each individual a value in four categories, or Action Modes, that indicates their level of insistence on a scale of 1 to 10 in that Action Mode (Kolbe, 2004). The four Action Modes are:
• Fact Finder – handling of information or facts
• Follow Thru – need to pattern or organize
• Quick Start – management of risk or uncertainty
• Implementor – interaction with space or tangibles
The Kolbe A (TM) index assigns each individual a value that indicates their level of insistence with 1-3 representing resistant, preventing problems in a particular Action Mode; 4-6 indicating accommodation, flexibility in a particular Action Mode; and 7-10 indicating insistence in an Action Mode, initiating solutions in that Action Mode (Kolbe, 2004).
To promote retention of conative diversity, this study examines conative diversity in two engineering student populations, a predominately freshmen population at Chandler Gilbert Community College and a predominately junior population at Arizona State University. Students in both population took a survey that asked them to self-report their GPA, satisfaction with required courses in their major, Kolbe ATM conative index, and how much their conative traits help them in each of the classes on the survey. The classes in the survey included two junior level classes at ASU, Engineering Business Practices and Structural Analysis; as well as four freshmen engineering classes, Physics Lecture, Physics Lab, English Composition, and Calculus I.
This study finds that student satisfaction has no meaningful correlation with student GPA.
The study also finds that engineering programs have a dearth of resistant Fact Finders from the freshmen level on and losses resistant Follow Thrus and insistent Quick Starts as time progresses. Students whose conative indices align well with the structure of the engineering program tend to consider their conative traits helpful to them in their engineering studies. Students whose conative indices misalign with the structure of the program report that they consider their strengths less helpful to them in their engineering studies.
This study recommends further research into the relationship between satisfaction with major and conation and into perceived helpfulness of conative traits by students. Educators should continue to use Kolbe A (TM) in the classroom and perform further research on the impacts of conation on diversity in engineering programs.
ContributorsSmith, Logan Farren (Author) / Seager, Thomas P. (Thesis director) / Adams, Elizabeth A. (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2015-05
Description
Transit-oriented developments (TODs) are a promising strategy to increase public transit use and, as a result, reduce personal car travel. By using TOD infill to increase urban population density and encourage transportation mode-shifting, the potential exists to reduce life-cycle per capita energy use and environmental impacts of the interdependent infrastructure systems. This project specifically examined the Gold Line of light rail and Orange Line of bus rapid transit in Los Angeles, CA.
ContributorsNahlik, Matthew John (Author) / Chester, Mikhail (Thesis director) / Pendyala, Ram (Committee member) / Pincetl, Stephanie (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor)
Created2013-05
Description
Engineers spend several years studying intense technical details of the processes that shape our world, yet few are exposed to classes addressing social behaviors or issues. Engineering culture creates specific barriers to addressing social science issues, such as unconscious bias, within engineering classrooms. I developed a curriculum that uses optical illusions, Legos, and the instructor's vulnerability to tackle unconscious bias in a way that addresses the barriers in engineering culture that prevent engineers from learning social science issues. Unconscious bias has documented long-term negative impacts on success and personal development, even in engineering environments. Creating a module in engineering education that addresses unconscious bias with the aim of reducing the negative effects of bias would benefit developing engineers by improving product development and team diversity. Engineering culture fosters disengagement with social issues through three pillars: depoliticization, technical/social dualism, and meritocracy. The developed curriculum uses optical illusions and Legos as proxies to start discussions about unconscious bias. The proxies allow engineers to explore their own biases without running into one of the pillars of disengagement that limits the engineer's willingness to discuss social issues. The curriculum was implemented in the Fall of 2017 in an upper-division engineering classroom as a professional communication module. The module received qualitatively positive feedback from fellow instructors and students. The curriculum was only implemented once by the author, but future implementations should be done with a different instructor and using quantitative data to measure if the learning objectives were achieved. Appendix A of the paper contains a lesson plan of the module that could be implemented by other instructors.
ContributorsLauber, Emily Anne (Author) / Wernimont, Jacqueline (Thesis director) / Mertz, Benjamin (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Productivity in the construction industry is an essential measure of production efficiency and economic progress, quantified by craft laborers' time spent directly adding value to a project. In order to better understand craft labor productivity as an aspect of lean construction, an activity analysis was conducted at the Arizona State University Palo Verde Main engineering dormitory construction site in December of 2016. The objective of this analysis on craft labor productivity in construction projects was to gather data regarding the efficiency of craft labor workers, make conclusions about the effects of time of day and other site-specific factors on labor productivity, as well as suggest improvements to implement in the construction process. Analysis suggests that supporting tasks, such as traveling or materials handling, constitute the majority of craft labors' efforts on the job site with the highest percentages occurring at the beginning and end of the work day. Direct work and delays were approximately equal at about 20% each hour with the highest peak occurring at lunchtime between 10:00 am and 11:00 am. The top suggestion to improve construction productivity would be to perform an extensive site utilization analysis due to the confined nature of this job site. Despite the limitations of an activity analysis to provide a complete prospective of all the factors that can affect craft labor productivity as well as the small number of days of data acquisition, this analysis provides a basic overview of the productivity at the Palo Verde Main construction site. Through this research, construction managers can more effectively generate site plans and schedules to increase labor productivity.
ContributorsFord, Emily Lucile (Author) / Grau, David (Thesis director) / Chong, Oswald (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The performance of the Alpha Sprayed Polyurethane Foam (SPF) roofing system is perceived as not an economical option when compared to a 20-year modified bitumen roofing system. Today, the majority of roofs are being replaced, rather than newly installed. The coating manufacturer, Neogard, implemented the Alpha roofing program to identify the best contractors in the industry and to measure their roof performance. The Alpha roof system has shown consistent high performance on over 230 million square feet of surveyed roof. The author proposes to identify if the Alpha roof system is renewable, has proven performance that competes with the traditional modified roofing system, and is a more economical option by evaluating an Alpha roof system installation and the performance of a 29-year-old Alpha roof system. The Dallas Independent School District utilized the Alpha program for William Lipscomb Elementary School in 2016. Dallas Fort Worth Urethane installed the Alpha SPF roof system with high customer satisfaction ratings. This roofing installation showed the value of the Alpha roof system by saving over 20% on costs for the installation and will save approximately 69% of costs on the recoating of the roof in 20 years. The Casa View Elementary School roof system was installed with a Neogard Permathane roof system in 1987. This roof was hail tested with ten drops from 17 feet 9 inches of 1-3/4-inch steel ball (9 out of 10 passed) and four drops from 17 feet 9 inches with a 3-inch diameter steel ball (2 out of 4 passed). The analysis of the passing and failing core samples show that the thickness of the top and base Alpha SPF coating is one of the major differences in a roof passing or failing the FM-SH hail test. Over the 40-year service life, the main difference of purchasing a 61,000 square feet Alpha SPF roof versus modified bitumen roof are savings of approximately $1,067,500. Past hail tests on Alpha SPF roof systems show its cost effectiveness with high customer satisfaction (9.8 out of 10), an over 40-year service life after a $6.00/SF recoat and savings of over $1M for DISD.
ContributorsZulanas, Charles J., IV (Author) / Kashiwagi, Dean T. (Thesis advisor) / Kashiwagi, Jacob S (Thesis advisor) / Chong, Oswald (Committee member) / Arizona State University (Publisher)
Created2017
Description
The solar energy sector has been growing rapidly over the past decade. Growth in renewable electricity generation using photovoltaic (PV) systems is accompanied by an increased awareness of the fault conditions developing during the operational lifetime of these systems. While the annual energy losses caused by faults in PV systems could reach up to 18.9% of their total capacity, emerging technologies and models are driving for greater efficiency to assure the reliability of a product under its actual application. The objectives of this dissertation consist of (1) reviewing the state of the art and practice of prognostics and health management for the Direct Current (DC) side of photovoltaic systems; (2) assessing the corrosion of the driven posts supporting PV structures in utility scale plants; and (3) assessing the probabilistic risk associated with the failure of polymeric materials that are used in tracker and fixed tilt systems.
As photovoltaic systems age under relatively harsh and changing environmental conditions, several potential fault conditions can develop during the operational lifetime including corrosion of supporting structures and failures of polymeric materials. The ability to accurately predict the remaining useful life of photovoltaic systems is critical for plants ‘continuous operation. This research contributes to the body of knowledge of PV systems reliability by: (1) developing a meta-model of the expected service life of mounting structures; (2) creating decision frameworks and tools to support practitioners in mitigating risks; (3) and supporting material selection for fielded and future photovoltaic systems. The newly developed frameworks were validated by a global solar company.
As photovoltaic systems age under relatively harsh and changing environmental conditions, several potential fault conditions can develop during the operational lifetime including corrosion of supporting structures and failures of polymeric materials. The ability to accurately predict the remaining useful life of photovoltaic systems is critical for plants ‘continuous operation. This research contributes to the body of knowledge of PV systems reliability by: (1) developing a meta-model of the expected service life of mounting structures; (2) creating decision frameworks and tools to support practitioners in mitigating risks; (3) and supporting material selection for fielded and future photovoltaic systems. The newly developed frameworks were validated by a global solar company.
ContributorsChokor, Abbas (Author) / El Asmar, Mounir (Thesis advisor) / Chong, Oswald (Committee member) / Ernzen, James (Committee member) / Arizona State University (Publisher)
Created2017
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
Women have evolved in the engineering profession over the decades. However, there is still a lot more room for female presence in the industry as women currently make up about 12-15% of working engineers. Based on many studies and surveys, it is clear that female confidence in their own performance and a feeling of belonging in the industry has evolved for the better. The studies and surveys also show that women still lack a certain confidence to get their engineering degree and then to pursue a career in engineering once they receive their degree. Research shows that the main cause for this is due to the stereotype that engineering is a masculine profession. Men and women both have this mindset because it has become a societal norm that most people go along with and do not even realize it. Unfortunately, it is very hard to overcome and change a societal norm, therefore, something needs to be done in order to fix this mindset. (Crawford). Based on studies and research, there are many ways the stereotype is being combatted. Social media has become a huge component in advocating for female engineers. Men and women are helping to fight the status quo by supporting female engineers and lobbying against people who think women do not belong in the industry. Industry professionals are teaming up with schools to figure out ways to make STEM programs more exciting for all young kids, but especially girls. They are also working to provide more mentors and role models for young girls in order to cheer them on and make them more confident in their abilities when learning and applying the STEM curriculum, as studies have proven that providing young girls with mentors can really help foster more female engineers in the long run. (Crawford). With all of the positive support and promotions of female engineers in the past few years, it is evident that women can certainly progress at a much faster pace than in previous decades.
ContributorsAcosta, Jazlyn (Co-author) / Venne, Hunter (Co-author) / Ward, Kristen (Thesis director) / Lou, Yingyan (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Construction industry performance (schedule, budget, and customer satisfaction) has not improved over the last 20 years. This investigation proposes that academic/industry research using actual project data may have more impact on improving industry performance than traditional survey-based research. The authors utilize the CIB and CIB W117 platforms to proliferate the concept of academic/industry test results to increase the impact on the construction industry. The authors propose to use the existing journal and then share the journal papers on an online platform (ResearchGate.net) ensuring a faster proliferation of the key academic/industry test results into the academic research community. The mechanism of the academic/industry test results will have more of an impact on industry practices than the traditional publication systems, which concentrate on literature reviews and surveys to collect industry opinions and analyze the information to change industry practices. The proliferation of industry research results will create transparency in the construction industry and the academic research community.
ContributorsGastelum, David (Author) / Kashiwagi, Dean T. (Thesis advisor) / Chong, Oswald (Committee member) / Badger, William (Committee member) / Arizona State University (Publisher)
Created2017