Journal Article Archives - Page 3 of 66

Rapid Assessment of Sulfate Resistance in Mortar and Concrete

Mousavinezhad, S., Toledo, W. K., Newtson, C. M., & Aguayo, F. (2024). Rapid Assessment of Sulfate Resistance in Mortar and Concrete. Materials, 17(19), 4678-. https://doi.org/10.3390/ma17194678

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Abstract

Extensive research has been conducted on the sulfate attack of concrete structures; however, the need to adopt the use of more sustainable materials is driving a need for a quicker test method to assess sulfate resistance. This work presents accelerated methods that can reduce the time required for assessing the sulfate resistance of mixtures by 70%. Class F fly ash has historically been used in concrete mixtures to improve sulfate resistance. However, environmental considerations and the evolving energy industry have decreased its availability, requiring the identification of economically viable and environmentally friendly alternatives to fly ash. Another challenge in addressing sulfate attack durability issues in concrete is that the standard sulfate attack test (ASTM C1012) is time-consuming and designed for only standard mortars (not concrete mixtures). To expedite the testing process, accelerated testing methods for both mortar and concrete mixtures were adopted from previous work to further the development of the accelerated tests and to assess the feasibility of testing the sulfate resistance of mortar and concrete mixtures rapidly. This study also established criteria for interpreting sulfate resistance for each of the test methods used in this work. A total of 14 mortar mixtures and four concrete mixtures using two types of Portland cement (Type I and Type I/II) and various supplementary cementitious materials (SCMs) were evaluated in this study. The accelerated testing methods significantly reduced the evaluation time from 12 months to 21 days for mortar mixtures and from 6 months to 56 days for concrete mixtures. The proposed interpretation method for mortar accelerated test results showed acceptable consistency with the ACI 318-19 interpretations for ASTM C1012 results. The interpretation methods proposed for the two concrete sulfate attack tests demonstrated excellent consistency with the ASTM C1012 results from mortar mixtures with the same cementitious materials combinations. Metakaolin was shown to improve sulfate resistance for both mortar and concrete mixtures, while silica fume and natural pozzolan had a limited impact. Using 15% metakaolin in mortar or concrete mixtures with Type I/II cement provided the best sulfate resistance.

Keywords

accelerated test method; concrete; metakaolin; mortar; natural pozzolan; sulfate attack

Innovative communication strategies for promoting urban wildlife habitat conservation

Waller, M., Cove, M. V., Daniels, J. C., & Yocom, K. P. (2025). Innovative communication strategies for promoting urban wildlife habitat conservation. Landscape and Urban Planning, 253, 105229-. https://doi.org/10.1016/j.landurbplan.2024.105229

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Abstract

The emerging recognition of the importance of urban habitat and wildlife for increasing biodiversity, driven partly by responses to climate change and urbanization, presents critical opportunities for urban biodiversity conservation and species recovery. However, effectively communicating these benefits to the public and policymakers remains a challenge for scientists and landscape architects with public perceptions, often shaped by diverse socio-cultural factors, serving as obstacles for garnering support. Our research explores innovative communication strategies through an intersectional analysis of planning and design communications and theory in museology and presents a structured approach in the use of charismatic species within interpretive studies to enhance public empathy and the potential for action. This research offers a valuable foundation for planning and design professionals, guiding their efforts to promote urban wildlife habitat and bridge the gaps between scientific knowledge and public advocacy.

Keywords

Urban wildlife habitat; Biodiversity conservation; Communication strategies

Advancing Active Transportation Through Mobility Justice and Centering Community

Baquero, B. I., Berney, R., Romano, E. F. T., Hicks, O., Getch, R., Hall, C., Mooney, S. J., Rosenberg, D., Shannon, K. L., Saelens, B. E., & Hoerster, K. D. (2024). Advancing Active Transportation Through Mobility Justice and Centering Community. Health Equity, 8(1), 72–730. https://doi.org/10.1089/heq.2024.0087

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Abstract

Objectives: We established a community–academic–policy partnership to examine mobility challenges and opportunities by centering members of a diverse South Seattle neighborhood.
Methods: Three participatory research methods were used: (a) 30- to 60-min qualitative interviews with community leaders (n = 12) and members (n = 16); (b) a photovoice with youth (n = 10); and (c) mobility audits. We also engaged extensively in community dissemination and advocacy.
Results: Four major themes emerged: experiences with the built environment; conflicting views on promoting active transportation; experiences of danger, violence, and racism while moving in the community; and pride and connections within the community. Mobility audit findings reinforced many community member messages about needed infrastructure changes. Participants consistently expressed the need for neighborhood and city-wide structural improvements to support transportation and mobility, including enhanced public transportation; better lighting, crosswalks, sidewalks, pavement, and curb cuts; and maintenance of a neighborhood mixed-use trail. Participants shared the importance of community connection while walking, rolling, or using public transit and wanted to maintain this experience.
Conclusions: Collectively, findings identified ways to increase nonmotorized transportation and public transit access, safety, and resilience, centering solutions on communities of color. We disseminated and amplified community recommendations to advance mobility justice in South Seattle via a community forum, developing a website, holding meetings with local leaders, and writing through print and electronic media. A key, novel strength of our project was the addition of community organizations, community–academic partners, and government leaders from the project’s inception. Local leaders should engage in mobility justice-focused community engagement to advance equity.

No Stakeholder Is an Island in the Drive to This Transition: Circular Economy in the Built Environment

Adabre, M. A., Chan, A. P. C., Darko, A., Edwards, D. J., Yang, Y., & Issahaque, S. (2024). No Stakeholder Is an Island in the Drive to This Transition: Circular Economy in the Built Environment. Sustainability, 16(15), 6422-. https://doi.org/10.3390/su16156422

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Abstract

Ensuring optimum utilisation of the Earth’s finite resources engenders the circular economy (CE) concept which has attracted the attention of policymakers and practitioners worldwide. As a bifurcated strategy which involves both scientific knowledge, advanced technologies and behavioural changes, the CE transition is sociotechnical in nature. Yet, prolific studies focus on scientific knowledge and technologies alone, while studies on promoting CE practices or built environment stakeholders’ behaviour are limited. Using Stakeholder Theory, a comprehensive literature review on CE drivers was conducted. Through a questionnaire survey of professionals, key drivers identified were deployed to develop a 20-driver model for CE transition in the built environment. The model is relevant to policymakers and practitioners because it highlights essential drivers for optimum resource allocation. Moreover, the findings apprise policymakers of the drivers that pertain to key stakeholders (i.e., professional and higher educational institutions, society and clients, government and firms), thus stating the requirements for driving each stakeholder to achieve this sociotechnical transition.

Keywords

circular economy; sociotechnical transition; sustainability; drivers; stakeholder theory; waste reduction

Big data analytics in the AEC industry: scientometric review and synthesis of research activities

Ohene, E., Nani, G., Antwi-Afari, M. F., Darko, A., Addai, L. A., & Horvey, E. (2024). Big data analytics in the AEC industry: scientometric review and synthesis of research activities. Engineering, Construction, and Architectural Management. https://doi.org/10.1108/ECAM-01-2024-0144

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Abstract

Unlocking the potential of Big Data Analytics (BDA) has proven to be a transformative factor for the Architecture, Engineering and Construction (AEC) industry. This has prompted researchers to focus attention on BDA in the AEC industry (BDA-in-AECI) in recent years, leading to a proliferation of relevant research. However, an in-depth exploration of the literature on BDA-in-AECI remains scarce. As a result, this study seeks to systematically explore the state-of-the-art review on BDA-in-AECI and identify research trends and gaps in knowledge to guide future research.
This state-of-the-art review was conducted using a mixed-method systematic review. Relevant publications were retrieved from Scopus and then subjected to inclusion and exclusion criteria. A quantitative bibliometric analysis was conducted using VOSviewer software and Gephi to reveal the status quo of research in the domain. A further qualitative analysis was performed on carefully screened articles. Based on this mixed-method systematic review, knowledge gaps were identified and future research agendas of BDA-in-AECI were proposed.
The results show that BDA has been adopted to support AEC decision-making, safety and risk assessment, structural health monitoring, damage detection, waste management, project management and facilities management. BDA also plays a major role in achieving construction 4.0 and Industry 4.0. The study further revealed that data mining, cloud computing, predictive analytics, machine learning and artificial intelligence methods, such as deep learning, natural language processing and computer vision, are the key methods used for BDA-in-AECI. Moreover, several data acquisition platforms and technologies were identified, including building information modeling, Internet of Things (IoT), social networking and blockchain. Further studies are needed to examine the synergies between BDA and AI, BDA and Digital twin and BDA and blockchain in the AEC industry.
The study contributes to the BDA-in-AECI body of knowledge by providing a comprehensive scope of understanding and revealing areas for future research directions beneficial to the stakeholders in the AEC industry.

Keywords

Big data; Big data analytics; AEC; Bibliometric analysis; Systematic analysis

Urban landscape affects scaling of transportation carbon emissions across geographic scales

Jung, M. C., Wang, T., Kang, M., Dyson, K., Dawwas, E. B., & Alberti, M. (2024). Urban landscape affects scaling of transportation carbon emissions across geographic scales. Sustainable Cities and Society, 113, 105656-. https://doi.org/10.1016/j.scs.2024.105656

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Abstract

Understanding the carbon dynamics of the transportation sector is necessary to mitigate global climate change. While urban scaling laws have been used to understand the impact of urban population size on carbon efficiency, the instability of these scaling relationships raises additional questions. Here, we examined the scaling of on-road transportation carbon emissions across 378 US metropolitan statistical areas (MSAs) using diverse urban landscape patterns and spatial units, from the MSA level down to 1 km grid cells. Beginning with a baseline scaling model that uses only population size, we expanded the model to include landscape metrics at each spatial scale based on correlation results. We found that: (1) urban landscape characteristics provide insights into carbon mechanisms not fully captured by population size alone, (2) the impact of population size on on-road carbon emissions transitions from linear to sub-linear scaling relationships as the geographic scale of analysis decreases, and (3) clustered urban developments can form carbon-efficient landscapes, while fragmented urban areas tend to be carbon-inefficient. Based on empirical evidence, this research advocates for hierarchical spatial planning and supports the implementation of policy measures aligned with smart growth principles to mitigate carbon pollution.

Let’s Be Clear-Health Impact Assessments or Assessing Health Impacts?

Kim, J., Dannenberg, A., Haigh, F., & Harris-Roxas, B. (2024). Let’s Be Clear—Health Impact Assessments or Assessing Health Impacts? Public Health Reviews, 45, 1607722-. https://doi.org/10.3389/phrs.2024.1607722

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Abstract

The article discusses the distinction between studies that assess health impacts and those that are specifically associated with health impact assessments (HIAs). It highlights the misuse of the term HIA in scholarly literature, where studies that evaluate health impacts are often labeled as HIAs. The authors emphasize that HIAs are intended to support decision-making and provide recommendations, rather than simply describing or evaluating health impacts. They suggest the need for better documentation of HIA recommendations and their impacts, as well as the development of reporting guidelines for academic HIA literature.

Keywords

decision making; health impact assessment; health risk assessment; policy recommendations; stakeholder engagement

Evaluating carbonation resistance and microstructural behaviors of calcium sulfoaluminate cement concrete incorporating fly ash and limestone powder

Mohammed, T., Torres, A., Aguayo, F., & Okechi, I. K. (2024). Evaluating carbonation resistance and microstructural behaviors of calcium sulfoaluminate cement concrete incorporating fly ash and limestone powder. Construction & Building Materials, 442, 137551-. https://doi.org/10.1016/j.conbuildmat.2024.137551

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Abstract

This study investigates the effects of accelerated carbonation on calcium sulfoaluminate (CSA) cement concrete, focusing on mixtures enhanced with 20 % fly ash (FA), 20 % remediated fly ash (RF), 15 % limestone powder (LP), and a combination of 20 % FA with 15 % LP (35 %). The study further evaluates the mechanical properties including compressive strength, splitting tensile strength, elastic modulus, along with drying shrinkage and bulk resistivity. To delve into the microstructural characteristics of moist curing versus carbonation exposure on the CSA cement system, X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were employed, particularly analyzing phase assemblage changes. The results show that the addition of FA reduced the carbonation depth in concrete mixtures over time (105 days). However, LP and the combination of FA and LP presented mixed effects. The microstructural analysis highlighted ettringite as the predominant phase in samples moist cured for 3 days. In contrast, carbonation-cured samples were characterized by different calcium carbonate (CaCO3) polymorphs alongside aluminum hydroxide (Al(OH)3) and residual ye'elimite, with the formation of low-pH carbonic acid facilitating the conversion of ettringite into CaCO3. This study highlights the impact of different SCMs on the durability and microstructural characteristics of CSA cement concrete, underscoring the interplay between curing methods, effects of SCM, and carbonation processes.

Keywords

Calcium sulfoaluminate cement (CSA); Carbonation; Limestone powder; Fly Ash; Microstructural analysis

Applications of blockchain for construction project procurement

Kim, M., & Kim, Y.-W. (2024). Applications of blockchain for construction project procurement. Automation in Construction, 165, 105550-. https://doi.org/10.1016/j.autcon.2024.105550

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Abstract

Blockchain technology has shown potential in enhancing project performance by instilling trust in data sharing among stakeholders, thereby encouraging the stakeholders to ensure a strategic acquisition and resource management through procurement activities. However, despite the recent research efforts on blockchain in the construction sector, there is a lack of knowledge of the status quo in that barely any research investigated the synergy of blockchain and procurement by recognizing the inextricable linkage between procurement management and project delivery system. This paper conducts a systematic review of 54 articles to assess blockchain's potential in addressing issues inherent in the current organizational structures and collaborative efforts. Findings offer profound insight into the current landscape of procurement-specific blockchain research, highlighting areas needing attention. This paper identified opportunities in construction procurement by investigating the extent to which the technology is integrated into the current project management context emphasizing integration and collaboration.

Keywords

Blockchain; Procurement; Construction industry; Procurement process; Project delivery system; Literature review

“All roads lead to Rome?” Performance evaluation across different types of community land trusts based on a large-scale survey

Wang, R., & Spicer, J. (2024). “All roads lead to Rome?” Performance evaluation across different types of community land trusts based on a large-scale survey. Journal of Urban Affairs, 1–22. https://doi.org/10.1080/07352166.2024.2371400

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Abstract

Community land trusts (CLTs) seek to keep homes and other urban spaces permanently affordable and community controlled. As their number across the United States has increased, different iterations of the CLT model seem to have proliferated in practice, stoking scholarly debate as to their varying outcomes and benefits. There has, however, been little attempt to empirically measure the relationship between this institutional diversity and outcomes. Applying institutional theory to a national CLT dataset, we identify five main organizational sub-types of CLT: traditional CLTs, start-up CLTs, government-housed CLTs, nonprofits with a CLT/shared equity (SE) program, and adapted CLTs. Statistical tests confirm a high degree of similarity in operational scope, organizational capacity, and performance outcomes across the most prominent sub-types. The limited statistical differences which can be identified are consistent with known CLT and urban institutional development processes. Further studies might seek to determine how consequential such limited differences may be.

Keywords

Community land trust; permanently affordable housing; historical institutionalism; community control; shared equity housing