Okechi, Ikechukwu K.; Aguayo, Federico; Torres, Anthony. (2022). Coefficient of Thermal Expansion of Concrete Produced with Recycled Concrete Aggregates. Journal of Civil Engineering and Construction, 11(2), 65-74.
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Abstract
This study presents a comparison between the coefficient of thermal expansion (CTE) of concrete produced with natural aggregate and that of concrete produced with recycled concrete aggregate. In order to achieve this, natural aggregate concrete (NAC) specimens were produced, tested, then crushed and sieved in the laboratory to obtain recycled concrete aggregates, which was then used in the production of recycled aggregate concrete (RAC) specimens. The RAC samples were then tested and compared to the NAC samples. The CTE testing was carried out using a AFTC2 CTE measurement system produced by Pine Instrument Company. In addition to CTE testing, the water absorption, specific gravity, and unit weight of the aggregates was determined. A vacuum impregnation procedure was used for the water absorption test. The recycled aggregate properties showed a significantly higher absorption capacity than that of the natural aggregates, while the unit weight and specific gravity of the recycled aggregate were lower than that of the natural aggregates. The average CTE results showed that both the NAC and the RAC samples expanded similarly. The results show that the CTE of RAC depends on the natural aggregate used in the NAC, which was recycled to produce the RAC. Also, there was no significant difference between the average CTE values of the RAC and that of NAC that could discredit the use of recycled aggregate in concrete.
Keywords
Coefficient of thermal expansion; Recycled concrete aggregate; Natural concrete aggregate.
Way, Thaisa. (2012). Richard Haag: New Eyes for Old. Sitelines: A Journal Of Place, 7(2), 6 – 8.
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Zhai, Wei; Yue, Haoyu; Deng, Yihan. (2022). Examining the Association between Urban Green Space and Viral Transmission of Covid-19 during the Early Outbreak. Applied Geography, 147.
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Abstract
Even though exposure to urban green spaces (UGS) has physical and mental health benefits during COVID-19, whether visiting UGS will exacerbate viral transmission and what types of counties would be more impacted remain to be answered. In this research, we adopted mobile phone data to measure the county-level UGS visi-tation across the United States. We developed a Bayesian model to estimate the effective production number of the pandemic. To consider the spatial dependency, we applied the geographically weighted panel regression to estimate the association between UGS visitation and viral transmission. We found that visitations to UGS may be positively correlated with the viral spread in Florida, Idaho, New Mexico, Texas, New York, Ohio, and Penn-sylvania. Especially noteworthy is that the spread of COVID-19 in the majority of counties is not associated with green space visitation. Further, we found that when people visit UGS, there may be a positive association be-tween median age and viral transmission in New Mexico, Colorado, and Missouri; a positive association between concentration of blacks and viral transmission in North Dakota, Minnesota, Wisconsin, Michigan, and Florida; and a positive association between poverty rate and viral transmission in Iowa, Missouri, Colorado, New Mexico, and the Northeast United States.
Keywords
Public Spaces; Viral Transmission; Covid-19; Extraterrestrial Beings; Covid-19 Pandemic; Smartphones; Cell Phones; Memes; Big Data; Urban Green Space; Geographical Information-system; Parks; Accessibility; Regression; Community; Stress; Health; Level
Celina Balderas Guzmán, PhD, is Assistant Professor in the Department of Landscape Architecture. Dr. Balderas’ research spans environmental planning, design, and science and focuses on climate adaptation to sea level rise on the coast and urban stormwater inland. On the coast, her work demonstrates specific ways that the climate adaptation actions of humans and adaptation of ecosystems are interdependent. Her work explores how these interdependencies can be maladaptive by shifting vulnerabilities to other humans or non-humans, or synergistic. Using ecological modeling, she has explored these interdependencies focusing on coastal wetlands as nature-based solutions. Her work informs cross-sectoral adaptation planning at a regional scale.
Inland, Dr. Balderas studies urban stormwater through a social-ecological lens. Using data science and case studies, her work investigates the relationship between stormwater pollution and the social, urban form, and land cover characteristics of watersheds. In past research, she developed new typologies of stormwater wetlands based on lab testing in collaboration with environmental engineers. The designs closely integrated hydraulic performance, ecological potential, and recreational opportunities into one form.
Her research has been funded by major institutions such as the National Science Foundation, National Socio-Environmental Synthesis Center, UC Berkeley, and the MIT Abdul Latif Jameel Water and Food Systems Lab. She has a PhD in the Department of Landscape Architecture and Environmental Planning from the University of California, Berkeley. Previously, she obtained masters degrees in urban planning and urban design, as well as an undergraduate degree in architecture all from MIT.
Narjes Abbasabadi, Ph.D., is an Assistant Professor in the Department of Architecture at the University of Washington. Dr. Abbasabadi also leads the Sustainable Intelligence Lab. Abbasabadi’s research centers on sustainability and computation in the built environment. Much of her work focuses on advancing design research efforts through developing data-driven methods, workflows, and tools that leverage the advances in digital technologies to enable augmented intelligence in performance-based and human-centered design. With an emphasis on multi-scale exploration, her research investigates urban building energy flows, human systems, and environmental and health impacts across scales—from the scale of building to the scale of neighborhood and city.
Abbasabadi’s research has been published in premier journals, including Applied Energy, Building and Environment, Energy and Buildings, Environmental Research, and Sustainable Cities and Society. She received honors and awards, including “ARCC Dissertation Award Honorable Mention” (Architectural Research Centers Consortium (ARCC), 2020), “Best Ph.D. Program Dissertation Award” (IIT CoA, 2019), and 2nd place in the U.S. Department of Energy (DOE)’s Race to Zero Design Competition (DOE, 2018). In 2018, she organized the 3rd IIT International Symposium on Buildings, Cities, and Performance. She served as editor of the third issue of Prometheus Journal, which received the 2020 Haskell Award from AIA New York, Center for Architecture.
Prior to joining the University of Washington, she taught at the University of Texas at Arlington and the Illinois Institute of Technology. She also has practiced with several firms and institutions and led design research projects such as developing design codes and prototypes for low-carbon buildings. Most recently, she practiced as an architect with Adrian Smith + Gordon Gill Architecture (AS+GG), where she has been involved in major projects, including the 2020 World Expo. Abbasabadi holds a Ph.D. in Architecture from the Illinois Institute of Technology and Master’s and Bachelor’s degrees in Architecture from Tehran Azad University.
Hutyra, Lucy R.; Yoon, Byungman; Hepinstall-Cymerman, Jeffrey; Alberti, Marina. (2011). Carbon Consequences of Land Cover Change and Expansion of Urban Lands: A Case Study in the Seattle Metropolitan Region. Landscape And Urban Planning, 103(1), 83 – 93.
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Abstract
Understanding the role humans play in modifying ecosystems through changing land cover is central to addressing our current and emerging environmental challenges. In particular, the consequences of urban growth and land cover change on terrestrial carbon budgets is a growing issue for our rapidly urbanizing planet. Using the lowland Seattle Statistical Metropolitan Area (MSA) region as a case study, this paper explores the consequences of the past land cover changes on vegetative carbon stocks with a combination of direct field measurements and a time series of remote sensing data. Between 1986 and 2007, the amount of urban land cover within the lowland Seattle MSA more than doubled, from 1316 km(2) to 2798 km(2), respectively. Virtually all of the urban expansion was at the expense of forests with the forested area declining from 4472 km(2) in 1986 to 2878 km(2) in 2007. The annual mean rate of urban land cover expansion was 1 +/- 0.6% year(-1). We estimate that the impact of these regional land cover changes on aboveground carbon stocks was an average loss of 1.2 Mg C ha(-1) yr(-1) in vegetative carbon stocks. These carbon losses from urban expansion correspond to nearly 15% of the lowland regional fossil fuel emissions making it an important, albeit typically overlooked, term in regional carbon emissions budgets. As we plan for future urban growth and strive for more ecologically sustainable cities, it is critical that we understand the past patterns and consequences of urban development to inform future land development and conservation strategies. (C) 2011 Elsevier B.V. All rights reserved.
Keywords
Sprawl; Growth; Carbon Cycle; Emissions; Land Cover; Urbanization; Seattle; Vegetation; Carbon; Carbon Sinks; Case Studies; Cities; Ecosystems; Forests; Fossil Fuels; Humans; Land Use; Planning; Remote Sensing; Time Series Analysis
James, Peter; Hart, Jaime E.; Hipp, J. Aaron; Mitchell, Jonathan A.; Kerr, Jacqueline; Hurvitz, Philip M.; Glanz, Karen; Laden, Francine. (2017). GPS-Based Exposure to Greenness and Walkability and Accelerometry-Based Physical Activity. Cancer Epidemiology Biomarkers & Prevention, 26(4), 525 – 532.
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Abstract
Background: Physical inactivity is a risk factor for cancer that may be influenced by environmental factors. Indeed, dense and well-connected built environments and environments with natural vegetation may create opportunities for higher routine physical activity. However, studies have focused primarily on residential environments to define exposure and self-reported methods to estimate physical activity. This study explores the momentary association between minute-level global positioning systems (GPS)-based greenness exposure and time-matched objectively measured physical activity. Methods: Adult women were recruited from sites across the United States. Participants wore a GPS device and accelerometer on the hip for 7 days to assess location and physical activity at minutelevel epochs. GPS records were linked to 250mresolution satellitebased vegetation data and Census Block Group-level U.S. Environmental Protection Agency (EPA) Smart Location Database walkability data. Minute-level generalized additive mixed models were conducted to test for associations between GPS measures and accelerometer count data, accounting for repeated measures within participant and allowing for deviations fromlinearity using splines. Results: Among 360 adult women (mean age of 55.3 +/- 10.2 years), we observed positive nonlinear relationships between physical activity and both greenness and walkability. In exploratory analyses, the relationships between environmental factors and physical activity were strongest among those who were white, had higher incomes, and who were middle-aged. Conclusions: Our results indicate that higher levels of physical activity occurred in areas with higher greenness and higher walkability. Impact: Findings suggest that planning and design policies should focus on these environments to optimize opportunities for physical activity. (C) 2017 AACR.
Keywords
Built Environments; Health Research; Breast-cancer; Obesity; Neighborhood; Validation; Validity; Walking; Risk; Energetics
Taufen, Anne; Yocom, Ken. (2021). Transitions In Urban Waterfronts: Imagining, Contesting, And Sustaining The Aquatic/terrestrial Interface. Sustainability, 13(1).
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Abstract
Urban waterfronts represent hybrid locations of ecological, economic, and social zones of transition and dispersal, spatially reified between land and water. Yet, through advancements in technology and the emergence of globally linked economies, the structure and function of urban waterfronts as economic and industrial drivers is becoming increasingly complex. As cities seek to redevelop their waterfronts in response to these changes, recent research and scholarship has focused on understanding the ecological, social, and economic benefits derived from urban waterfronts. This research reveals that their benefits are unevenly distributed among local and regional populations as sites of accumulated inequity and inaccessibility that are generative for only a relatively small percentage of the people living in a metropolitan area. Set within this paradoxical nexus, this paper frames a call to scientists, planners, academics, and waterfront activists to expand urban waterfront research from an indicator and benefits model to incorporate three conceptual tools for better understanding key dimensions of waterfront reclamation within the context of green infrastructure research: urban hybridity, functional performance and hierarchies of access. We explore these key dimensions in relation to the waterfront redevelopment of Tacoma, Washington, USA. By acknowledging the hybridity of urban waterfronts, we illustrate that their relative performance and accessibility require ongoing empirical study and practical intervention. Our theoretical explorations plot some of the potential areas of investigation for examining the structural and functional transitions of urban waterfronts as critical locations for green infrastructure development for the 21st century.
Keywords
Place Attachment; Community Participation; Cities; Justice; Indicators; Challenges; Resilience; Governance; Space; Urban Waterfronts; Complexity; Urban Hybridity; Functional Performance; Hierarchies Of Access; Public Access; Stormwater Management; Infrastructure; Reclamation; Green Aspects; Waterfront Development; Urban Areas; Terrestrial Environments; Waterfronts; Economics; Hierarchies; Redevelopment; Regulation; Dispersal; Economic Activity; Shorelines; Regions; Terrestrial Ecosystems; Sustainable Development; Structure-function Relationships; Ports; Rivers; Metropolitan Areas; Urbanization; United States--us
Kondo, Michelle C.; Rivera, Rebeca; Rullman, Stan, Jr. (2012). Protecting the Idyll but Not the Environment: Second Homes, Amenity Migration and Rural Exclusion in Washington State. Landscape And Urban Planning, 106(2), 174 – 182.
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Abstract
Researchers are beginning to take notice of amenity migration processes and their impacts in exurban areas of the U.S. Our research explores second-home owners as contributors to processes of amenity migration. Using a mixed-method approach combining spatial data and interview analyses, we investigate both the structural and behavioral aspects of amenity migration in San Juan and Okanogan counties of Washington State. Results indicate that second-home owners' desire for privacy and escape is reflected in patterns of spatial isolation among second homes in the study area. These patterns have potentially significant ecological effects. Second-home owners also seek to protect their investments by supporting regulations which support their version of a rural idyll. Therefore, policy-makers should be wary of strategies to promote regulations which promote aesthetic rather than social and ecological function. (C) 2012 Elsevier B.V. All rights reserved.
Keywords
Land-use; Colorado Mountains; Political Ecology; Landscape Change; United-states; Gentrification; Residents; Attitudes; Growth; West; Amenity Migration; Second Homes; Mixed-method Research
Nilon, Charles H.; Aronson, Myla F. J.; Cilliers, Sarel S.; Dobbs, Cynnamon; Frazee, Lauren J.; Goddard, Mark A.; O’Neill, Karen M.; Roberts, Debra; Stander, Emilie K.; Werner, Peter; Winter, Marten; Yocom, Ken P. (2017). Planning For The Future Of Urban Biodiversity: A Global Review Of City-scale Initiatives. Bioscience, 67(4), 331 – 341.
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Abstract
Cities represent considerable opportunities for forwarding global biodiversity and sustainability goals. We developed key attributes for conserving biodiversity and for ecosystem services that should be included in urban-planning documents and reviewed 135 plans from 40 cities globally. The most common attributes in city plans were goals for habitat conservation, air and water quality, cultural ecosystem services, and ecological connectivity. Few plans included quantitative targets. This lack of measurable targets may render plans unsuccessful for an actionable approach to local biodiversity conservation. Although most cities include both biodiversity and ecosystem services, each city tends to focus on one or the other. Comprehensive planning for biodiversity should include the full range of attributes identified, but few cities do this, and the majority that do are mandated by local, regional, or federal governments to plan specifically for biodiversity conservation. This research provides planning recommendations for protecting urban biodiversity based on ecological knowledge.
Keywords
Sustainability; Urban Planning; Urban Biodiversity; Urban Ecology (biology); Water Quality; Air Quality; Biodiversity Conservation; Ecosystem Services; Governance; Policy Regulation; Green Infrastructure; Climate-change; Human Health; Cities; Opportunities; Metaanalysis; Framework; Richness