Alam, M. S., & Abbasabadi, N. (2026). A CFD-Integrated Parametric Framework for Evaluating Passive Carbon-Capture Enclosure Performance. Architecture, 6(2), 65. https://doi.org/10.3390/architecture6020065
View Publication
Abstract
Integrating direct air carbon capture (DAC) into buildings offers a promising pathway for reducing atmospheric CO2, yet the role of architectural design in enhancing passive carbon-capture performance remains underexplored. This study presents a computational framework developed to optimize architectural design and enclosure geometry for enhanced passive airflow, using mass-flow rate as a proxy for the comparative assessment of carbon absorption potential. Implemented within Rhino3D and Grasshopper using Ladybug and Eddy3D, the workflow integrates weather data and CFD simulation to compute segmented mass-flow rates through stacked capture trays. The framework simplifies traditionally complex CFD processes by introducing a custom segmented mass-flow calculation approach that enables comparative performance assessment during early-stage design. Results confirm the validity of the proposed workflow, revealing that façade rotation can modify total mass flow by up to 96.5%; seasonal wind variability can cause airflow to range from approximately 8.5 kg/s in January to 169.5 kg/s in May in Seattle. Spatial configuration can alter airflow by up to an order of magnitude and introduce substantial spatial heterogeneity within capture zones. This research establishes a performance-driven design framework that enables architectural geometry to actively enhance passive carbon-capture integration, positioning building design as a measurable contributor to climate mitigation strategies. Ultimately, this work bridges architectural design and carbon-capture engineering, supporting interdisciplinary approaches to scalable, climate-responsive building systems.
Keywords
direct air capture; computational fluid dynamics; carbon-positive solutions; climate-responsive architecture; sustainable design; nature-based solutions; design computation
Akerele, D. D. (2026). CBR performance of lime-stabilized and geotextile lateritic soils under soaked and unsoaked conditions. Journal of Infrastructure Preservation and Resilience, 7(1). https://doi.org/10.1186/s43065-026-00190-2
View Publication
Abstract
Lateritic soils are commonly used in pavement subgrades in tropical regions, but their performance can be limited by plasticity, moisture sensitivity, and low bearing capacity. This study evaluates the plasticity, compaction, and California Bearing Ratio (CBR) response of three lateritic soils treated with hydrated lime and woven geotextile reinforcement under unsoaked and selected soaked conditions. Lime contents of 0%, 4%, 5%, and 6% by dry soil mass were investigated, and selected geotextile placements were introduced within compacted CBR specimens. The results show that moderate lime dosages substantially improved the unsoaked CBR of Samples A and B, with peak lime-only values of 62.92% at 4% lime for Sample A and 72.85% at 5% lime for Sample B. In contrast, Sample C, which had the highest fines content and plasticity index, showed limited improvement with the tested lime contents and remained a poor-performing material. Geotextile reinforcement improved CBR when compared with untreated no-geotextile soil, especially in several 0% lime configurations. However, at the optimum lime contents for Samples A and B, geotextile-reinforced specimens did not exceed the corresponding same-lime no-geotextile controls. These findings indicate that lime stabilization and geotextile reinforcement should not be assumed to provide additive strength gains. Instead, reinforcement effectiveness depends on soil type, lime dosage, curing and conditioning history, geotextile placement, and the soil-geotextile system’s ability to mobilize tensile resistance during penetration. The study is therefore presented as a descriptive laboratory CBR investigation, with limitations arising from incomplete replicate-level records, differing curing histories among specimen groups, and a selected rather than a full factorial soaked test matrix.
The Center for Timber Innovation in the Built Environment at the University of Washington advances the understanding and adoption of mass timber as a sustainable, carbon-smart building material. Through interdisciplinary research, hands-on learning, and community partnerships, CTIBE drives innovation that supports both resilient communities and the natural systems that sustain them.
With Washington’s forests at a crossroads, responsibly managed second- and third-growth softwoods can provide affordable, climate-smart solutions for our state’s growing housing and infrastructure needs.
Profs. H.W. Chris Lee, Rachel Berney, and Lingzi Wu hosted a successful stakeholder kick-off meeting for the WSDOT-funded Shore Power: Bremerton Transportation Center eMobility Project. The meeting drew strong participation from Washington State Ferries, Kitsap Transit, the City of Bremerton, Kitsap County, Puget Sound Energy, the Port of Bremerton, and the U.S. Navy. Agencies engaged in productive discussions on mobility challenges, electrification opportunities, and multimodal planning needs at the Bremerton Transportation Center. This collaborative launch sets a strong foundation for…
Amudjie, J., Chan, A. P. C., Darko, A., Debrah, C., & Agyekum, K. (2025). CircularBIM: Future needs at the convergence of building information modelling and the circular economy. Automation in Construction, 176, 106250. doi:10.1016/j.autcon.2025.106250
View Publication
Abstract
The progressions of industrial revolutions have enabled diverse digital technologies in architecture, engineering, construction and operation (AECO), with Building Information Modelling (BIM) gaining notable attention. Concurrently, the circular economy (CE) has emerged as a crucial strategy for addressing socio-economic issues such as waste, resource depletion, and climate change. However, limitations within BIM or CE implementations have led to these persisting socio-economic challenges. This paper presents a comprehensive state-of-the-art review on the convergence of BIM and CE (hereafter, CircularBIM), utilizing a mixed-method approach (bibliometric and systematic review techniques), analysing 89 relevant studies. Key research trends identified include life cycle assessments, deconstruction, BIM-based systems, waste management, and energy efficiency. This paper suggests future research should integrate recommender systems for CircularBIM, employ real-time performance integrated CircularBIM directory, increase expert studies and broaden parameters integration for CircularBIM. Ultimately, this paper aims to enhance CircularBIM implementation in the AECO sector, providing insights for all stakeholders.
Keywords
Building information modelling; Carbon emissions; CircularBIM; Circular economy; PRISMA; Review
Darko Amos, Weerasinghe Lichini Nikesha Kumari, Chan Albert Ping Chuen, & Wu Lingzi. (2025). Partial Least Squares Structural Equation Modeling of Challenges to Existing Residential Building Net Zero Carbon Retrofitting. Journal of Construction Engineering and Management, 151(8), 05025005. doi:10.1061/JCEMD4.COENG-16471
View Publication
Abstract
Residential buildings play a significant role in global energy usage and carbon emissions. In Hong Kong, they contribute to 27% of energy usage and associated carbon emissions. Retrofitting residential buildings to net zero carbon (NZC) is an efficient way to lower carbon emissions and prevent climate change. However, the widespread adoption of NZC retrofitting in the industry has been limited by several challenges, which have rarely been addressed in research. This study intended to evaluate the linkages among various challenges while assessing their impacts on NZC retrofitting of existing residential buildings. Data were collected through a questionnaire survey with 123 residential building occupants in Hong Kong, whose perspectives are largely ignored in existing building retrofit research. Partial least squares structural equation modeling (PLS-SEM) was used to analyze the data. Outcomes indicated that technical and social challenges have a considerable negative effect on residential building NZC retrofitting. In addition, this study highlights the connections between challenge categories and presents a predictive model illustrating the relationships between challenges and residential building NZC retrofitting. Theoretically, the outcomes of this study provide new insights into the relationships between residential building NZC retrofitting challenges and their interactive effects, revealing that the challenges influence one another and do not exist in isolation. Practically, the findings could be useful to policymakers and practitioners seeking to promote NZC retrofitting by enabling the development of effective policies and strategies to mitigate the identified challenges.
Assistant Professor in the Department of Construction Management Dr. Amos Darko has been named to the editorial board of the American Society of Civil Engineers (ASCE) Journal of Construction Engineering and Management as an Assistant Specialty Editor for the Sustainable Construction area. This appointment serves as an important recognition of Dr. Darko’s expertise and research in sustainable construction. Dr. Darko will play a key role in reviewing submitted manuscripts to this area of the journal. We congratulate Dr. Darko on…
Ababio, B.K., Lu, W., Darko, A. and Agyekum, K. (2025), “A cross-economy examination of circular procurement implementation in construction: key drawbacks and strategies toward a sustainable built environment”, Smart and Sustainable Built Environment, Vol. ahead-of-print No. ahead-of-print. https://doi.org/10.1108/SASBE-09-2024-0349
View Publication
Abstract
Purpose
Circular procurement (CP) systems have become essential in the face of resource scarcity, environmental degradation and the need for cost savings. However, its widespread adoption for construction projects has been notably slow. This study sets out to examine the barriers to CP implementation and explore potential solutions to accelerate its uptake within the global construction industry.
Design/methodology/approach
The study employs a quantitative approach to examine perspectives of 132 procurement experts from a split sample of two geo-economic contexts: developed and developing economies. It determines, categorizes and evaluates the barriers and strategies associated with CP implementation using descriptive statistics, principal components and comparative agreement analysis.
Findings
The findings revealed major impediments at different system levels including inadequate leadership and commitment for circular practices, little knowledge of CP opportunities, linear construction business setup and weak policies on circularity. These drawbacks were prevalent among experts from both geo-economic contexts. However, other barriers like cultural and industry behaviors were not commonly considered significant. Some effective strategies recommended by industry professionals were centered around organizational dynamics, industry nudging and financing, skill and cultural adaptation, and innovation and development mechanisms. The cross-economy comparison highlighted varying degrees of consensus in the significance of the strategies, indicative that approaches to dealing with challenges vary across economies.
Originality/value
This study, the first of its kind in the construction sector, offers insights into CP implementation dynamics, i.e. challenges and strategies relevant to different geoeconomic contexts. The comparative approach between developed and developing economies adds a unique dimension to the understanding of the peculiarities of CP adoptions and what strategies may apply.
Keywords
Circular procurement (CP); barriers; strategies; construction sector; geoeconomic context; comparative analyses
Linyan Chen, Amos Darko, Fan Zhang, Albert P.C. Chan, Qiang Yang,Can large language models replace human experts? Effectiveness and limitations in building energy retrofit challenges assessment,Building and Environment,Volume 276,2025,112891, ISSN 0360-1323,
https://doi.org/10.1016/j.buildenv.2025.112891.
View Publication
Abstract
Retrofitting existing buildings is essential to improve energy efficiency and achieve carbon neutrality in the fight against global climate change. Large language models (LLMs) have recently attracted significant attention for their ability to process data efficiently. While LLMs have emerged as useful tools for various tasks, their potential to replace human experts in assessing building energy retrofit challenges remains unexplored. This research explores the potential of replacing human experts with LLMs by evaluating four mainstream LLM chatbots and comparing their performance against a human expert benchmark through semantic similarity and text correlation metrics. It answers the research question: can LLMs replace human experts in assessing the challenges to building energy retrofits? Prompt engineering techniques, including zero-shot and chain-of-thought (CoT) prompting, were employed to guide LLM responses. Results show that LLMs perform well in identifying challenges but are less reliable in ranking them. CoT prompting improves challenge ranking accuracy but does not enhance challenge identification. Incorporating domain-specific knowledge in prompts significantly enhances LLM performance, whereas prompts designed to simulate experts have notable limitations in improving LLM performance. Furthermore, there are no significant performance differences among LLMs, including their advanced versions. While LLMs can streamline the initial identification of building energy retrofit challenges, they cannot fully replace expert judgment in ranking challenges due to their lack of tacit knowledge. This research provides valuable insight into the capabilities and limitations of LLMs in the challenge assessment, offering practical guidance for industry practitioners seeking to integrate LLMs into their building energy efficiency practices.
Keywords
Large language model; Building energy retrofit; Challenges assessment; Prompt engineering; Generative artificial intelligence
Akerele, D. D., Aguayo, F., & Wu, L. (2025). Portland Limestone Cement in Concrete Pavement and Bridge Decks: Performance Evaluation and Future Directions. Buildings, 15(5), 660. https://doi.org/10.3390/buildings15050660
View Publication
Abstract
With the rising demand for sustainable infrastructure, addressing the limitations of Ordinary Portland Cement (OPC) is crucial, particularly for exposed structures such as pavements and bridge decks. Portland limestone cement (PLC) is a sustainable alternative that delivers environmental benefits and comparable performance. This study used a systematic review and meta-analysis with a random-effects model to evaluate PLC’s strength development, durability, and sustainability. The findings indicate that PLC generally matches or surpasses OPC in terms of compressive strength, freeze–thaw resistance, and sulfate durability. However, its setting time and early-age cracking require further optimization, especially in cold climates. Additionally, this study highlights the fire performance advantages of PLC and its enhanced chloride resistance. The analysis identified critical research gaps, including long-term field performance and regional adaptation to extreme environmental conditions. These findings contribute to a deeper understanding of PLC’s role in sustainable construction and offer future research directions on hybrid cements and admixture compatibility.
Keywords
Portland limestone cement (PLC); type 1L cement; concrete pavement; bridge deck; sustainability; low-carbon; CO2 reduction