Buildings

22 pages, 6303 KB

Open AccessArticle

Analysis of the Upper Limit of the Stability of High and Steep Slopes Supported by a Combination of Anti-Slip Piles and Reinforced Soil Under the Seismic Effect

by Wei Luo, Gequan Xiao, Zhi Tao, Jingyu Chen, Zhulong Gong and Haifeng Wang

Buildings 2025, 15(15), 2806; https://doi.org/10.3390/buildings15152806 - 7 Aug 2025

Viewed by 283

Abstract

The reinforcement effect of single-reinforced soil support under external loading has limitations, and it is difficult for it to meet engineering stability requirements. Therefore, the stability analysis of slopes supported by a combination of anti-slip piles and reinforced soil under the seismic loading [...] Read more.

The reinforcement effect of single-reinforced soil support under external loading has limitations, and it is difficult for it to meet engineering stability requirements. Therefore, the stability analysis of slopes supported by a combination of anti-slip piles and reinforced soil under the seismic loading effect needs an in-depth study. Based on the upper-bound theorem of limit analysis and the strength-reduction technique, this study establishes an upper-bound stability model for high–steep slopes that simultaneously considers seismic action and the combined reinforcement of anti-slide piles and reinforced soil. A closed-form safety factor is derived. The theoretical results are validated against published data, demonstrating satisfactory agreement. Finally, the MATLAB R2022a sequential quadratic programming method is used to optimize the objective function, and the Optum G2 2023 software is employed to analyze the factors influencing slope stability due to the interaction between anti-slide piles and geogrids. The research indicates that the horizontal seismic acceleration coefficient k_h exhibits a significant negative correlation with the safety factor F_s. Increases in the tensile strength T of the reinforcing materials, the number of layers n, and the length l all significantly improve the safety factor F_s of the reinforced-soil slope. Additionally, as l increases, the potential slip plane of the slope shifts backward. For slope support systems combining anti-slide piles and reinforced soil, when the length of the geogrid is the same, adding anti-slide piles can significantly improve the slope’s safety factor. As anti-slide piles move from the toe to the crest of the slope, the safety factor first decreases and then increases, indicating that the optimal reinforcement position for anti-slide piles should be in the middle to lower part of the slope body. The length of the anti-slip piles should exceed the lowest layer of the geogrid to more effectively utilize the blocking effect of the pile ends on the slip surface. The research findings can provide a theoretical basis and practical guidance for parameter optimization in high–steep slope support engineering. Full article

(This article belongs to the Section Building Structures)

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19 pages, 3585 KB

Open AccessArticle

The Effect of Xylitol as a Natural Admixture on the Properties of Alkali-Activated Slag/Fly Ash-Based Materials

by Jie Song, Haowei Hu and Weitong Yu

Buildings 2025, 15(15), 2805; https://doi.org/10.3390/buildings15152805 - 7 Aug 2025

Viewed by 300

Abstract

This study introduces xylitol, a natural compound, as a multifunctional additive to enhance the performance of alkali-activated slag/fly ash materials (AASFMs). A systematic investigation was conducted to elucidate xylitol’s mechanism in modifying AASFM properties, including fresh behavior, hydration kinetics, compressive strength, and autogenous [...] Read more.

This study introduces xylitol, a natural compound, as a multifunctional additive to enhance the performance of alkali-activated slag/fly ash materials (AASFMs). A systematic investigation was conducted to elucidate xylitol’s mechanism in modifying AASFM properties, including fresh behavior, hydration kinetics, compressive strength, and autogenous shrinkage. The experimental findings demonstrated that xylitol significantly delayed early-age hydration while promoting more extensive hydration at later stages. Specifically, the initial and final setting times of AASFM pastes were extended by 640% and 370%, respectively, and paste flowability increased by 30%. At a 0.2% dosage, xylitol markedly reduced porosity and refined the microstructure of AASFMs, leading to improved mechanical properties. The 3-day and 28-day compressive strengths were enhanced by 39.8% and 39.7%, respectively, while autogenous shrinkage was suppressed by 61.4%. These results demonstrate the multifunctional potential of xylitol in AASFMs, serving as an effective retarder, plasticizer, strength enhancer, and shrinkage reducer. Notably, the refined pore structure induced by xylitol may also mitigate the risks of the alkali–silica reaction, though further durability validation is warranted. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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24 pages, 4356 KB

Open AccessArticle

A Study on the Effects of Distinct Visual Elements and Their Combinations in Window Views on Stress and Emotional States

by Ping Zhang, Tao Yang, Yunque Bo, Wenqi Song, Wenyu Liu, Wei Ni, Wenjie Gao and Xiaoyan Qi

Buildings 2025, 15(15), 2804; https://doi.org/10.3390/buildings15152804 - 7 Aug 2025

Viewed by 370

Abstract

As people spend extended periods of time indoors, stress and negative emotions caused by work have become increasingly difficult to ignore. Observing window views is widely considered an effective method to alleviate stress and promote mental health. However, the specific visual elements within [...] Read more.

As people spend extended periods of time indoors, stress and negative emotions caused by work have become increasingly difficult to ignore. Observing window views is widely considered an effective method to alleviate stress and promote mental health. However, the specific visual elements within these views that contribute to stress reduction and the differential restorative benefits across varying compositions remain insufficiently understood. This study focuses on four major visual elements commonly seen through windows: sky, buildings, greenery, and roads. Using a horizontal layering approach, nine window views were created based on different proportions of these elements. Participants were exposed to these views, and their responses were evaluated through the positive and negative affect scale (PANAS), as well as electroencephalographic (EEG) data acquisition. The findings indicate that greenery exhibits the most pronounced positive effect on stress mitigation and the enhancement of positive affect, while the presence of roads is more likely to elicit negative emotional responses. Additionally, the visual richness and structural completeness of the window scenes are found to significantly impact restorative outcomes. These findings provide empirical insights for landscape and architectural design aimed at improving psychological well-being. Full article

(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)

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40 pages, 4862 KB

Open AccessReview

Exploring Purpose-Driven Methods and a Multifaceted Approach in Dam Health Monitoring Data Utilization

by Zhanchao Li, Ebrahim Yahya Khailah, Xingyang Liu and Jiaming Liang

Buildings 2025, 15(15), 2803; https://doi.org/10.3390/buildings15152803 - 7 Aug 2025

Viewed by 363

Abstract

Dam monitoring tracks environmental variables (water level, temperature) and structural responses (deformation, seepage, and stress) to assess safety and performance. Structural health monitoring (SHM) refers to the systematic observation and analysis of the structural condition over time, and it is essential in maintaining [...] Read more.

Dam monitoring tracks environmental variables (water level, temperature) and structural responses (deformation, seepage, and stress) to assess safety and performance. Structural health monitoring (SHM) refers to the systematic observation and analysis of the structural condition over time, and it is essential in maintaining the safety, functionality, and long-term performance of dams. This review examines monitoring data applications, covering structural health assessment methods, historical motivations, and key challenges. It discusses monitoring components, data acquisition processes, and sensor roles, stressing the need to integrate environmental, operational, and structural data for decision making. Key objectives include risk management, operational efficiency, safety evaluation, environmental impact assessment, and maintenance planning. Methodologies such as numerical modeling, statistical analysis, and machine learning are critically analyzed, highlighting their strengths and limitations and the demand for advanced predictive techniques. This paper also explores future trends in dam monitoring, offering insights for engineers and researchers to enhance infrastructure resilience. By synthesizing current practices and emerging innovations, this review aims to guide improvements in dam safety protocols, ensuring reliable and sustainable dam operations. The findings provide a foundation for the advancement of monitoring technologies and optimization of dam management strategies worldwide. Full article

(This article belongs to the Section Construction Management, and Computers & Digitization)

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26 pages, 5677 KB

Open AccessArticle

CFD Investigation on the Thermal Comfort for an Office Room

by Mazen M. Othayq

Buildings 2025, 15(15), 2802; https://doi.org/10.3390/buildings15152802 - 7 Aug 2025

Viewed by 262

Abstract

Heating, Ventilating, and Air Conditioning (HVAC) systems are important and essential for use in our daily comfort, either in homes, work, or transportation. And it is crucial to study the air movement coming from the inlet diffuser for a better design to enhance [...] Read more.

Heating, Ventilating, and Air Conditioning (HVAC) systems are important and essential for use in our daily comfort, either in homes, work, or transportation. And it is crucial to study the air movement coming from the inlet diffuser for a better design to enhance thermal comfort and energy consumption. The primary objective of the presented work is to investigate the thermal comfort within a faculty office occupied by two faculty members using the Computational Fluid Dynamics (CFD) methodology. First, an independent mesh study was performed to reduce the uncertainty related to the mesh size. In addition, the presented CFD approach was validated against available experimental data from the literature. Then, the effect of inlet air temperature and velocity on air movement and temperature distribution is investigated using Ansys Fluent. To be as reasonable as possible, the persons who occupy the office, lights, windows, tables, the door, and computers are accounted for in the CFD simulation. After that, the Predicted Mean Vote (PMV) was evaluated at three different locations inside the room, and the approximate total energy consumption was obtained for the presented cases. The CFD results showed that, for the presented cases, the sensation was neutral with the lowest energy consumption when the supply air velocity was 1 m/s and the temperature was 21 °C. Full article

(This article belongs to the Section Building Energy, Physics, Environment, and Systems)

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17 pages, 2354 KB

Open AccessArticle

Gender Differences: The Role of Built Environment and Commute in Subjective Well-Being

by Chen Gui, Yuze Cao, Fanyuan Yu, Yue Zhou and Chaoying Yin

Buildings 2025, 15(15), 2801; https://doi.org/10.3390/buildings15152801 - 7 Aug 2025

Viewed by 212

Abstract

The literature has shown extensive interest in exploring the factors of subjective well-being (SWB). However, most research has conducted cross-sectional analysis of the built environment (BE), commute, and SWB, and little is known about gender differences in their connections. Based on two periods [...] Read more.

The literature has shown extensive interest in exploring the factors of subjective well-being (SWB). However, most research has conducted cross-sectional analysis of the built environment (BE), commute, and SWB, and little is known about gender differences in their connections. Based on two periods of survey data of 4297 respondents from China, the study performs a cross-sectional and longitudinal examination of whether the BE and commute have effects on SWB, and how the effects differ between men and women. The results reveal that BE features, including destination accessibility and residential density, significantly affect SWB, with stronger impacts observed among men. Men benefit more from greater accessibility and are more negatively affected by higher residential density than women. In contrast, commute mode and duration influence SWB in similar ways for both genders. A shift from nonactive to active commuting improves well-being for men and women alike. Furthermore, certain life events produce gender-specific effects. For instance, childbirth increases SWB for men but decreases it for women. These findings highlight the importance of gender-sensitive planning in building inclusive urban and transportation environments that enhance population well-being. Full article

(This article belongs to the Special Issue New Trends in Built Environment and Mobility)

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27 pages, 6700 KB

Open AccessArticle

Experimental and Computational Analysis of Large-Amplitude Flutter in the Tacoma Narrows Bridge: Wind Tunnel Testing and Finite Element Time-Domain Simulation

by Bishang Zhang and Ledong Zhu

Buildings 2025, 15(15), 2800; https://doi.org/10.3390/buildings15152800 - 7 Aug 2025

Viewed by 259

Abstract

Nonlinear wind-induced vibrations and coupled static–dynamic instabilities pose significant challenges for long-span suspension bridges, especially under large-amplitude and high-angle-of-attack conditions. However, existing studies have yet to fully capture the mechanisms behind large-amplitude torsional flutter. To address this, wind tunnel experiments were performed on [...] Read more.

Nonlinear wind-induced vibrations and coupled static–dynamic instabilities pose significant challenges for long-span suspension bridges, especially under large-amplitude and high-angle-of-attack conditions. However, existing studies have yet to fully capture the mechanisms behind large-amplitude torsional flutter. To address this, wind tunnel experiments were performed on H-shaped bluff sections and closed box girders using a high-precision five-component piezoelectric balance combined with a custom support system. Complementing these experiments, a finite element time-domain simulation framework was developed, incorporating experimentally derived nonlinear flutter derivatives. Validation was achieved through aeroelastic testing of a 1:110-scale model of the original Tacoma Narrows Bridge and corresponding numerical simulations. The results revealed Hopf bifurcation phenomena in H-shaped bluff sections, indicated by amplitude-dependent flutter derivatives and equivalent damping coefficients. The simulation results showed less than a 10% deviation from experimental and historical wind speed–amplitude data, confirming the model’s accuracy. Failure analysis identified suspenders as the critical failure components in the Tacoma collapse. This work develops a comprehensive performance-based design framework that improves the safety, robustness, and resilience of long-span suspension bridges against complex nonlinear aerodynamic effects while enabling cost-effective, targeted reinforcement strategies to advance modern bridge engineering. Full article

(This article belongs to the Special Issue Advanced Structural Techniques for Seismic and Wind Resilience: Innovations in Safety and Performance)

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35 pages, 7791 KB

Open AccessArticle

Inspection Data-Driven Machine Learning Models for Predicting the Remaining Service Life of Deteriorating Bridge Decks

by Gitae Roh, Changsu Shim and Hyunhye Song

Buildings 2025, 15(15), 2799; https://doi.org/10.3390/buildings15152799 - 7 Aug 2025

Viewed by 317

Abstract

The bridge deck is more vulnerable to deterioration than other structural components. This is due to its direct exposure to environmental factors such as vehicular loads, chloride ingress, and freeze–thaw cycles. The resulting accelerated degradation often results in a serviceability life that is [...] Read more.

The bridge deck is more vulnerable to deterioration than other structural components. This is due to its direct exposure to environmental factors such as vehicular loads, chloride ingress, and freeze–thaw cycles. The resulting accelerated degradation often results in a serviceability life that is shorter than the intended design life. However, the absence of standardized condition assessment methods coupled with clear definitions of remaining service life has limited the establishment of rational guidelines for repair and strengthening. In a bid to address this lack, this study focuses on PSC-I type bridges in South Korea, utilizing long-term field inspection data to analyze environmental, structural, and material factors—including reinforcement corrosion, chloride diffusion, and freeze–thaw actions. Environmental zoning was applied based on regional conditions, while structural zoning was performed according to load characteristics, thereby allowing the classification of deck regions into moment zones and cantilever sections. Machine learning models were employed to identify dominant deterioration mechanisms, with the validity of the zoning classification being evaluated via model accuracy and SHAP value analysis. Additionally, a regression-based approach was proposed to estimate the remaining service life of the bridge deck for each corrosion phase, thereby providing a quantitative framework for durability assessment and maintenance planning. Full article

(This article belongs to the Special Issue Knowledge Management in the Building and Construction Industry)

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28 pages, 3313 KB

Open AccessArticle

Assessing Drivers, Barriers and Policy Interventions for Implementing Digitalization in the Construction Industry of Pakistan

by Waqas Arshad Tanoli

Buildings 2025, 15(15), 2798; https://doi.org/10.3390/buildings15152798 - 7 Aug 2025

Viewed by 354

Abstract

Digitalization is rapidly reshaping the global construction industry; however, its adoption in developing countries, such as Pakistan, remains limited and uneven. Hence, this study investigates and evaluates the current status of digital technology integration in Pakistan’s construction industry, with a primary focus on [...] Read more.

Digitalization is rapidly reshaping the global construction industry; however, its adoption in developing countries, such as Pakistan, remains limited and uneven. Hence, this study investigates and evaluates the current status of digital technology integration in Pakistan’s construction industry, with a primary focus on key tools, implementation challenges, and necessary policy interventions. Using a three-phase mixed-method approach involving a literature review, expert interviews, and a nationwide survey, this research identifies Building Information Modeling, Geographic Information Systems, and E-Procurement as essential technologies with strong potential to improve transparency, efficiency, and collaboration. However, adoption is hindered by a lack of awareness, limited technical expertise, and the absence of a cohesive national policy. This study also highlights that the private sector shows greater readiness compared to the public sector; however, systemic barriers persist across both sectors. Based on stakeholder insights, a three-part policy strategy was also proposed. This includes establishing a national regulatory framework, investing in capacity-building programs, and providing financial or institutional incentives to encourage the adoption of these measures. The findings emphasize that digitalization is not just a technical upgrade; it represents a pathway to improved governance and more efficient infrastructure delivery. With timely and coordinated policy action, the construction industry in Pakistan can align itself with global innovation trends and move toward a more sustainable and digitally empowered future. Full article

(This article belongs to the Section Construction Management, and Computers & Digitization)

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26 pages, 674 KB

Open AccessArticle

Toward Standardised Construction Pipeline Data: Conceptual Minimum Dataset Framework

by Elrasheid Elkhidir, James Olabode Bamidele Rotimi, Tirth Patel, Taofeeq D. Moshood and Suzanne Wilkinson

Buildings 2025, 15(15), 2797; https://doi.org/10.3390/buildings15152797 - 7 Aug 2025

Viewed by 281

Abstract

The construction industry is a cornerstone of New Zealand (NZ)’s economic growth, yet strategic infrastructure planning is constrained by fragmented and inconsistent pipeline data. Despite the increasing availability of construction pipeline datasets in NZ, their limited clarity, interoperability, and standardisation impede effective forecasting, [...] Read more.

The construction industry is a cornerstone of New Zealand (NZ)’s economic growth, yet strategic infrastructure planning is constrained by fragmented and inconsistent pipeline data. Despite the increasing availability of construction pipeline datasets in NZ, their limited clarity, interoperability, and standardisation impede effective forecasting, policy development, and investment alignment. These challenges are compounded by disparate data structures, inconsistent reporting formats, and semantic discrepancies across sources, undermining cross-agency coordination and long-term infrastructure governance. To address this issue, the study begins by assessing the quality of four prominent pipeline datasets using Wang and Strong’s multidimensional data quality framework. This evaluation provides a necessary foundation for identifying the structural and semantic barriers that limit data integration and informed decision-making. The analysis examines four dimensions of data quality: accessibility, intrinsic quality, contextual relevance, and representational clarity. The findings reveal considerable inconsistencies in data fields, classification systems, and levels of detail across the datasets. Building on these insights, this study also develops a conceptual minimum dataset (MDS) framework comprising three core thematic categories: project identification, project characteristics, and project budget and timing. The proposed conceptual MDS includes unified data definitions, standardised reporting formats, and semantic alignment to enhance cross-platform usability and data confidence. This framework applies to the New Zealand context and is designed for replication in other jurisdictions, supporting the global push toward open, high-quality infrastructure data. The study contributes to the construction informatics and infrastructure planning by offering a practical solution to a critical data governance issue and introducing a transferable methodology for developing minimum data standards in the built environment to enable more informed, coordinated, and evidence-based decision-making. Full article

(This article belongs to the Special Issue Big Data and Machine/Deep Learning in Construction)

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16 pages, 19063 KB

Open AccessArticle

Numerical Analysis of Diaphragm Wall Deformation and Surface Settlement Caused by Dewatering and Excavation at Center and End Positions in a Subway Foundation Pit

by Kaifang Yang, Mingdong Jiang, Minliang Chi and Guohui Feng

Buildings 2025, 15(15), 2796; https://doi.org/10.3390/buildings15152796 - 7 Aug 2025

Viewed by 255

Abstract

Metro foundation pits are important components of urban infrastructure projects. Dewatering and excavation are essential stages in foundation pit construction; however, this process can significantly induce groundwater drawdown, as well as diaphragm wall deformation and surface settlement. Based on a subway station foundation [...] Read more.

Metro foundation pits are important components of urban infrastructure projects. Dewatering and excavation are essential stages in foundation pit construction; however, this process can significantly induce groundwater drawdown, as well as diaphragm wall deformation and surface settlement. Based on a subway station foundation pit project, in this study, we employ three-dimensional numerical software to simulate the process of dewatering and excavation. A refined model is used to investigate groundwater seepage, the deformation of the retaining structure, and surface settlement under spatial effects. The finite element model accounts for stratified excavation and applied prestress conditions for the support system within the foundation pit. Its accuracy is validated through a comparison and analysis with measured data from the actual foundation pit. The results indicate that foundation pit excavation leads to significant groundwater drawdown around the pit and the formation of a characteristic “funnel-shaped” drawdown curve. Moreover, extending the diaphragm wall length contributes to maintaining a higher external groundwater level surrounding the foundation pit. The horizontal displacement of the diaphragm wall increases progressively during dewatering and excavation, and the bending moment of the diaphragm wall exhibits a trend consistent with its horizontal displacement. Surface settlement decreases as the length of the diaphragm wall increases. Full article

(This article belongs to the Special Issue Research on Rock Mechanics and Rock Engineering, Geotechnical Engineering and Mining Sciences in Construction—2nd Edition)

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30 pages, 6787 KB

Open AccessArticle

Modeling Ontology-Based Decay Analysis and HBIM for the Conservation of Architectural Heritage: The Big Gate and Adjacent Curtain Walls in Ibb, Yemen

by Basema Qasim Derhem Dammag, Dai Jian, Abdulkarem Qasem Dammag, Yahya Alshawabkeh, Sultan Almutery, Amer Habibullah and Ahmad Baik

Buildings 2025, 15(15), 2795; https://doi.org/10.3390/buildings15152795 - 7 Aug 2025

Viewed by 283

Abstract

The conservation of architectural heritage (AH) in regions threatened by natural and human-induced factors requires interdisciplinary approaches that integrate physical documentation with semantic modeling. This study introduces a comprehensive framework combining Historic Building Information Modeling (HBIM) with ontology-based modeling aligned with the CIDOC [...] Read more.

The conservation of architectural heritage (AH) in regions threatened by natural and human-induced factors requires interdisciplinary approaches that integrate physical documentation with semantic modeling. This study introduces a comprehensive framework combining Historic Building Information Modeling (HBIM) with ontology-based modeling aligned with the CIDOC Conceptual Reference Model (CIDOC CRM). Focusing on the Big Gate and adjacent curtain walls in Ibb, Yemen, where the gate is entirely lost, the study reconstructs the structure using historical photographs, eyewitness accounts, and analogical references. The methodology incorporates UAV and terrestrial photogrammetry surveys, point cloud generation, and semantic enrichment using Autodesk Revit V. 2024 and Protégé V. 5.5. Decay phenomena such as cracks, efflorescence, and disintegration were ontologically classified and spatially linked to the HBIM model, revealing deterioration patterns concerning historical phases and environmental exposure. The resulting system enables dynamic documentation, facilitates strategic conservation planning, and enhances data interoperability across heritage platforms. The proposed framework is transferable to other heritage sites, supporting both the conservation of extant structures and the reconstruction of lost ones. Full article

(This article belongs to the Special Issue BIM Methodology and Tools Development/Implementation)

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32 pages, 2341 KB

Open AccessReview

Human and Multi-Robot Collaboration in Indoor Environments: A Review of Methods and Application Potential for Indoor Construction Sites

by Francis Xavier Duorinaah, Mathanraj Rajendran, Tae Wan Kim, Jung In Kim, Seulbi Lee, Seulki Lee and Min-Koo Kim

Buildings 2025, 15(15), 2794; https://doi.org/10.3390/buildings15152794 - 7 Aug 2025

Viewed by 585

Abstract

The integration of robotic agents into complex indoor construction environments is increasing, particularly through human–robot collaboration (HRC) and multi-robot collaboration (MRC). These collaborative frameworks hold great potential to enhance productivity and safety. However, indoor construction environments present unique challenges, such as dynamic layouts, [...] Read more.

The integration of robotic agents into complex indoor construction environments is increasing, particularly through human–robot collaboration (HRC) and multi-robot collaboration (MRC). These collaborative frameworks hold great potential to enhance productivity and safety. However, indoor construction environments present unique challenges, such as dynamic layouts, constrained spaces, and variable lighting conditions, which complicate the safe and effective deployment of collaborative robot teams. Existing studies have primarily addressed various HRC and MRC challenges in manufacturing, logistics, and outdoor construction, with limited attention given to indoor construction settings. To this end, this review presents a comprehensive analysis of human–robot and multi-robot collaboration methods within various indoor domains and critically evaluates the potential of adopting these methods for indoor construction. This review presents three key contributions: (1) it provides a structured evaluation of current human–robot interaction techniques and safety-enhancing methods; (2) it presents a summary of state-of-the-art multi-robot collaboration frameworks, including task allocation, mapping, and coordination; and (3) it identifies major limitations in current systems and provides research directions for enabling scalable, robust, and context-aware collaboration in indoor construction. By bridging the gap between current robotic collaboration methods and the needs of indoor construction, this review lays the foundation for the development of adaptive and optimized collaborative robot deployment frameworks for indoor built environments. Full article

(This article belongs to the Special Issue Automation and Robotics in Building Design and Construction)

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26 pages, 1794 KB

Open AccessReview

Activating and Enhancing the Energy Flexibility Provided by a Pipe-Embedded Building Envelope: A Review

by Xiaochen Yang, Yanqing Li, Xiaoqiong Li, Khaled A. Metwally and Yan Ding

Buildings 2025, 15(15), 2793; https://doi.org/10.3390/buildings15152793 - 7 Aug 2025

Viewed by 392

Abstract

Building thermal mass offers a cost-effective solution to enhance the integration of energy supply and demand in dynamic energy systems. Thermally activated building systems (TABS), incorporating embedded heat tubes, shows strong potential for energy flexibility. However, the significant thermal inertia of TABS also [...] Read more.

Building thermal mass offers a cost-effective solution to enhance the integration of energy supply and demand in dynamic energy systems. Thermally activated building systems (TABS), incorporating embedded heat tubes, shows strong potential for energy flexibility. However, the significant thermal inertia of TABS also imposes challenges to precise load shift and indoor climate control. This review synthesizes key research on the effective demand-side management of TABS from multiple perspectives. It examines and compares various TABS configurations, including floor, ceiling, and wall systems. Differences in heat transfer performance between heating and cooling result in distinct application preferences for each type. The integration of advanced materials, such as phase change materials (PCM), can further enhance energy flexibility. TABS flexibility is primarily activated through adjustments to indoor operative temperature, with relevant influencing factors and regulatory constraints analyzed and discussed. Key aspects of optimizing building energy flexibility, including simulation methods and control strategies for TABS, are reviewed from both theoretical and practical perspectives. The energy and economic performance of TABS under various control strategies is analyzed in detail. This review provides insights to support the optimal design and operation of TABS within dynamic energy systems and to enhance the energy flexibility of building envelopes. Full article

(This article belongs to the Topic Multidimensional Exploration of Low-Carbon Buildings: Synergistic Optimization of Energy System and Intelligent Control of Built Environment)

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21 pages, 885 KB

Open AccessArticle

Synergistic Effect of Community Environment on Cognitive Function in Elderly People

by Tao Shen, Ying Li and Man Zhang

Buildings 2025, 15(15), 2792; https://doi.org/10.3390/buildings15152792 - 7 Aug 2025

Viewed by 379

Abstract

With rapid global aging, the community environment has become a critical factor influencing cognitive health in older adults. However, most existing studies focus on single environmental attributes and rely on linear analytical methods, which fail to capture the complex and synergistic effects of [...] Read more.

With rapid global aging, the community environment has become a critical factor influencing cognitive health in older adults. However, most existing studies focus on single environmental attributes and rely on linear analytical methods, which fail to capture the complex and synergistic effects of community features. Guided by an integrated theoretical perspective on environmental psychology, aging, and cognitive health, this study examines how multiple community environmental factors jointly affect cognitive function in elderly people. A case study was conducted among 215 older residents in Shanghai, China. An exploratory factor analysis (EFA) identified the following five key dimensions of community environment: pedestrian friendliness, blue–green spaces, infrastructure, space attractiveness, and safety. We then applied both Partial Least Squares Structural Equation Modeling (PLS-SEM) and Fuzzy Set Qualitative Comparative Analysis (fsQCA) to reveal linear and configurational relationships. The findings showed that pedestrian friendliness, blue–green spaces, and space attractiveness significantly enhance cognitive health, while fsQCA highlighted multiple pathways that underscore the non-linear and synergistic interactions among environmental features. These results provide theoretical insights into the mechanisms linking community environments and cognitive function and offer practical guidance for designing age-friendly communities. Full article

(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)

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22 pages, 16891 KB

Open AccessArticle

Efficient Hyperparameter Optimization Using Metaheuristics for Machine Learning in Truss Steel Structure Cross-Section Prediction

by Donwoo Lee, Seunghyeon Noh, Jeonghyun Kim and Seungjae Lee

Buildings 2025, 15(15), 2791; https://doi.org/10.3390/buildings15152791 - 7 Aug 2025

Viewed by 317

Abstract

The optimal design of truss structures is one of the most complex problems, as it requires achieving high stiffness and stability while pursuing lightweight structures. With the recent advancements in AI technologies, machine learning-based approaches for predicting the optimal cross-sectional areas of truss [...] Read more.

The optimal design of truss structures is one of the most complex problems, as it requires achieving high stiffness and stability while pursuing lightweight structures. With the recent advancements in AI technologies, machine learning-based approaches for predicting the optimal cross-sectional areas of truss structures have garnered significant attention from researchers. However, the design problem of truss structures poses substantial challenges for machine learning models due to the highly diverse and nonlinear characteristics of the optimal cross-sectional distributions, which may hinder effective learning. To address these limitations, the importance of hyperparameter optimization (HPO) has been increasingly recognized. This paper employs metaheuristic algorithms, which are efficient in searching for global optima, to perform HPO on 10-bar and 17-bar truss structure datasets. By balancing exploitation and exploration capabilities, metaheuristic algorithms demonstrate superior performance and time efficiency compared to conventional HPO methods. The results underscore the critical role of hyperparameters in machine learning-based truss structure design and suggest that leveraging metaheuristic algorithm-based HPO holds significant potential for addressing complex structural design problems in future applications. Full article

(This article belongs to the Special Issue Research on Structural Analysis and Design of Civil Structures)

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28 pages, 7766 KB

Open AccessArticle

Feature Importance Analysis for Compressive Bearing Capacity of HSCM Piles Based on GA-BPNN

by Fangzhou Chu, Jiakuan Ma, Yang Luan and Shilin Chen

Buildings 2025, 15(15), 2790; https://doi.org/10.3390/buildings15152790 - 7 Aug 2025

Viewed by 245

Abstract

To address the complex pile–soil interaction mechanisms in predicting the compressive bearing capacity of HSCM piles (Helix Stiffened Cement Mixing piles) in marine soft soil regions, this study proposes an intelligent prediction method based on a GA-BPNN (Genetic Algorithm-Optimized Back Propagation Neural Network). [...] Read more.

To address the complex pile–soil interaction mechanisms in predicting the compressive bearing capacity of HSCM piles (Helix Stiffened Cement Mixing piles) in marine soft soil regions, this study proposes an intelligent prediction method based on a GA-BPNN (Genetic Algorithm-Optimized Back Propagation Neural Network). A high-quality database comprising 1243 data points was established through finite element numerical simulations. By integrating data preprocessing techniques and the GA-BPNN model, the study systematically investigated the influence of helical blade spacing H₁ and H₂, strength ratio C_ref/S_u, and diameter ratio D_sc/D_H on bearing capacity. The results demonstrate that the GA-BPNN model achieves a prediction accuracy of 99.07%, with a mean squared error (MSE) of 7.20 × 10⁻³ and a coefficient of determination R² of 0.990. SHAP value analysis reveals that the strength ratio and diameter ratio are the dominant factors, exhibiting nonlinear relationships with bearing capacity characterized by saturation effects and threshold-dependent behavior. Laboratory tests further confirm strong correlations between cement–soil strength C_ref, formed pile diameter D_sc, and bearing capacity. The findings indicate that the GA-BPNN model provides an efficient and accurate approach for predicting the bearing capacity of HSCM piles, offering a reliable basis for engineering parameter optimization. Full article

(This article belongs to the Section Building Structures)

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60 pages, 8707 KB

Open AccessReview

Automation in Construction (2000–2023): Science Mapping and Visualization of Journal Publications

by Mohamed Marzouk, Abdulrahman A. Bin Mahmoud, Khalid S. Al-Gahtani and Kareem Adel

Buildings 2025, 15(15), 2789; https://doi.org/10.3390/buildings15152789 - 7 Aug 2025

Viewed by 714

Abstract

This paper presents a scientometric review that provides a quantitative perspective on the evolution of Automation in Construction Journal (AICJ) research, emphasizing its developmental paths and emerging trends. The study aims to analyze the journal’s growth and citation impact over time. It also [...] Read more.

This paper presents a scientometric review that provides a quantitative perspective on the evolution of Automation in Construction Journal (AICJ) research, emphasizing its developmental paths and emerging trends. The study aims to analyze the journal’s growth and citation impact over time. It also seeks to identify the most influential publications and the cooperation patterns among key contributors. Furthermore, the study explores the journal’s primary research themes and their evolution. Accordingly, 4084 articles were identified using the Web of Science (WoS) database and subjected to a multistep analysis using VOsviewer version 1.6.18 and Biblioshiny as software tools. First, the growth and citation of the publications over time are inspected and evaluated, in addition to ranking the most influential documents. Second, the co-authorship analysis method is applied to visualize the cooperation patterns between countries, organizations, and authors. Finally, the publications are analyzed using keyword co-occurrence and keyword thematic evolution analyses, revealing five major research clusters: (i) foundational optimization, (ii) deep learning and computer vision, (iii) building information modeling, (iv) 3D printing and robotics, and (v) machine learning. Additionally, the analysis reveals significant growth in publications (54.5%) and citations (78.0%) from 2018 to 2023, indicating the journal’s increasing global influence. This period also highlights the accelerated adoption of digitalization (e.g., BIM, computational design), increased integration of AI and machine learning for automation and predictive analytics, and rapid growth of robotics and 3D printing, driving sustainable and innovative construction practices. The paper’s findings can help readers and researchers gain a thorough understanding of the AICJ’s published work, aid research groups in planning and optimizing their research efforts, and inform editorial boards on the most promising areas in the existing body of knowledge for further investigation and development. Full article

(This article belongs to the Topic Construction Project Management and Infrastructure Sustainability)

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1 pages, 127 KB

Open AccessRetraction

RETRACTED: Sariyev et al. A Comparative Study of the Rheological Properties of a Fly Ash-Based Geopolymer Reinforced with PP Fiber for 3D Printing: An Experimental and Numerical Approach. Buildings 2024, 14, 2068

by Bakytzhan Sariyev, Alisher Konysbekov, Assel Jexembayeva and Marat Konkanov

Buildings 2025, 15(15), 2788; https://doi.org/10.3390/buildings15152788 - 7 Aug 2025

Viewed by 158

Abstract

The journal retracts the article “A Comparative Study of the Rheological Properties of a Fly Ash-Based Geopolymer Reinforced with PP Fiber for 3D Printing: An Experimental and Numerical Approach” [...] Full article

19 pages, 2093 KB

Open AccessArticle

Risk Assessment of Prefabricated Building Projects Based on the G1-CRITIC Method and Cloud Model: A Case Study from China

by Zhipeng Zhang, Lini Duan and Xinran Du

Buildings 2025, 15(15), 2787; https://doi.org/10.3390/buildings15152787 - 7 Aug 2025

Viewed by 328

Abstract

To enhance the ability to identify and analyze the construction safety risks of prefabricated building projects, this paper explores the risk factors affecting the construction safety of prefabricated buildings from the perspective of the construction stage. Based on the WSR theory, this paper [...] Read more.

To enhance the ability to identify and analyze the construction safety risks of prefabricated building projects, this paper explores the risk factors affecting the construction safety of prefabricated buildings from the perspective of the construction stage. Based on the WSR theory, this paper identifies risk-influencing factors from five dimensions: personnel, materials, management, technology, and environment, and constructs a safety risk assessment index system. This paper establishes a risk assessment model based on the G1-CRITIC method and cloud model. Firstly, it quantitatively analyzes the weights of the risk indicators for prefabricated building construction, and then evaluates the specific degree of impact of each indicator on the construction risk of this type of project. The research results show that the project is at the low-risk level, but there are still some potential risks in terms of material and technical factors, which require close attention and targeted management. The evaluation results obtained by applying this model are consistent with the current actual situation of prefabricated building construction, further demonstrating the applicability of this model. The risk assessment model proposed in this paper, by focusing on a specific type of risk, comprehensively incorporates the fuzziness and randomness of risk factors, thereby more effectively capturing the dynamic characteristics of risk evolution. This model can effectively evaluate the level of safety risk management and plays a positive role in reducing the incidence of engineering accidents. Furthermore, it also provides practical experience that can be drawn upon by risk managers of similar projects which holds significant theoretical value and practical guiding significance. Full article

(This article belongs to the Section Construction Management, and Computers & Digitization)

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15 pages, 6966 KB

Open AccessArticle

A Concise Grid-Based Model Revealing the Temporal Dynamics in Indoor Infection Risk

by Pengcheng Zhao and Xiaohong Zheng

Buildings 2025, 15(15), 2786; https://doi.org/10.3390/buildings15152786 - 6 Aug 2025

Viewed by 340

Abstract

Determining the transmission routes of pathogens in indoor environments is challenging, with most studies limited to specific case analyses and pilot experiments. When pathogens are instantaneously released by a patient in an indoor environment, the peak infection risk may not occur immediately but [...] Read more.

Determining the transmission routes of pathogens in indoor environments is challenging, with most studies limited to specific case analyses and pilot experiments. When pathogens are instantaneously released by a patient in an indoor environment, the peak infection risk may not occur immediately but may instead appear at a specific moment during the pathogen’s spread. We developed a concise model to describe the temporal crest of infection risk. The model incorporates the transmission and degradation characteristics of aerosols and surface particles to predict infection risks via air and surface routes. Only four real-world outbreaks met the criteria for validating this phenomenon. Based on the available data, norovirus is likely to transmit primarily via surface touch (i.e., the fomite route). In contrast, crests of infection risk were not observed in outbreaks of respiratory diseases (e.g., SARS-CoV-2), suggesting a minimal probability of surface transmission in such cases. The new model can serve as a preliminary indicator for identifying different indoor pathogen transmission routes (e.g., food, air, or fomite). Further analyses of pathogens’ transmission routes require additional evidence. Full article

(This article belongs to the Special Issue Development of Indoor Environment Comfort)

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33 pages, 3396 KB

Open AccessArticle

Enhancing Smart and Zero-Carbon Cities Through a Hybrid CNN-LSTM Algorithm for Sustainable AI-Driven Solar Power Forecasting (SAI-SPF)

by Haytham Elmousalami, Felix Kin Peng Hui and Aljawharah A. Alnaser

Buildings 2025, 15(15), 2785; https://doi.org/10.3390/buildings15152785 - 6 Aug 2025

Viewed by 375

Abstract

The transition to smart, zero-carbon cities relies on advanced, sustainable energy solutions, with artificial intelligence (AI) playing a crucial role in optimizing renewable energy management. This study evaluates state-of-the-art AI models for solar power forecasting, emphasizing accuracy, reliability, and environmental sustainability. Using operational [...] Read more.

The transition to smart, zero-carbon cities relies on advanced, sustainable energy solutions, with artificial intelligence (AI) playing a crucial role in optimizing renewable energy management. This study evaluates state-of-the-art AI models for solar power forecasting, emphasizing accuracy, reliability, and environmental sustainability. Using operational data from Benban Solar Park in Egypt and Sakaka Solar Power Plant in Saudi Arabia, two of the world’s largest solar installations, the research highlights the effectiveness of hybrid AI techniques. The hybrid Convolutional Neural Network–Long Short-Term Memory (CNN-LSTM) model outperformed other models, achieving a Mean Absolute Percentage Error (MAPE) of 2.04%, Root Mean Square Error (RMSE) of 184, Mean Absolute Error (MAE) of 252, and R² of 0.99 for Benban, and an MAPE of 2.00%, RMSE of 190, MAE of 255, and R² of 0.98 for Sakaka. This model excels at capturing complex spatiotemporal patterns in solar data while maintaining low computational CO₂ emissions, supporting sustainable AI practices. The findings demonstrate the potential of hybrid AI models to enhance the accuracy and sustainability of solar power forecasting, thereby contributing to efficient, resilient, and zero-carbon urban environments. This research provides valuable insights for policymakers and stakeholders aiming to advance smart energy infrastructure. Full article

(This article belongs to the Special Issue Intelligent Automation in Construction Management)

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19 pages, 3032 KB

Open AccessReview

The Microstructure and Modification of the Interfacial Transition Zone in Lightweight Aggregate Concrete: A Review

by Jian Zhou, Yiding Dong, Tong Qiu, Jiaojiao Lv, Peng Guo and Xi Liu

Buildings 2025, 15(15), 2784; https://doi.org/10.3390/buildings15152784 - 6 Aug 2025

Viewed by 585

Abstract

The interfacial transition zone (ITZ) significantly influences the mechanical properties and durability of lightweight aggregate concrete (LWAC), yet existing research on the ITZ in LWAC remains fragmented due to varied characterization techniques, inconsistent definitions of ITZ thickness and porosity, and the absence of [...] Read more.

The interfacial transition zone (ITZ) significantly influences the mechanical properties and durability of lightweight aggregate concrete (LWAC), yet existing research on the ITZ in LWAC remains fragmented due to varied characterization techniques, inconsistent definitions of ITZ thickness and porosity, and the absence of standardized performance metrics. This review focuses primarily on structural LWAC produced with artificial and natural lightweight aggregates, with intended applications in high-performance civil engineering structures. This review systematically analyzes the microstructure, composition, and physical properties of the ITZ, including porosity, microhardness, and hydration product distribution. Quantitative data from recent studies are highlighted—for instance, incorporating 3% nano-silica increased ITZ bond strength by 134.12% at 3 days and 108.54% at 28 days, while using 10% metakaolin enhanced 28-day compressive strength by 24.6% and reduced chloride diffusion by 81.9%. The review categorizes current ITZ enhancement strategies such as mineral admixtures, nanomaterials, surface coatings, and aggregate pretreatment methods, evaluating their mechanisms, effectiveness, and limitations. By identifying key trends and research gaps—particularly the lack of predictive models and standardized characterization methods—this review aims to synthesize key findings and identify knowledge gaps to support future material design in LWAC. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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13 pages, 2040 KB

Open AccessArticle

Study on the Shear Characteristics of the Frozen Soil–Concrete Interface at Different Roughness Levels

by Ming Xie, Mengqi Xu, Fangbo Xu, Zhangdong Wang, Lie Yin and Xiangdong Wu

Buildings 2025, 15(15), 2783; https://doi.org/10.3390/buildings15152783 - 6 Aug 2025

Viewed by 317

Abstract

The shear characteristics of the frozen soil–concrete interface are core parameters in frost heave resistance design in cold-region engineering, and the influence mechanism of interface roughness on these characteristics is not clear. In this study, the regulatory effect of different roughness levels (R-0 [...] Read more.

The shear characteristics of the frozen soil–concrete interface are core parameters in frost heave resistance design in cold-region engineering, and the influence mechanism of interface roughness on these characteristics is not clear. In this study, the regulatory effect of different roughness levels (R-0 to R-4) on the interfacial freezing strength was quantitatively analyzed for the first time through direct shear tests, and the evolution characteristics of the contribution ratio of the ice cementation strength were revealed. The results show that the peak shear strength of the interface increases significantly with the roughness (when the normal stress is 400 kPa and the water content is 14%, the increase in R-4 is 47.7% compared with R-0); the ice cementation strength increases synchronously and its contribution ratio increases with the increase in roughness. Although the absolute value of the residual strength increase is small, the relative amplitude is larger (178.5% increase under the same working conditions). The peak cohesion increased significantly with the roughness (R-0 to R-4 increased by 268.6%), while the residual cohesion decreased. The peak and residual internal friction angle increased slightly with the roughness. The study clarifies the differential influence mechanism of roughness on the interface’s shear parameters and provides a key quantitative basis for the anti-frost heave design of engineering interfaces in cold regions. Full article

(This article belongs to the Special Issue Building Foundation Analysis: Soil–Structure Interaction—2nd Edition)

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19 pages, 3586 KB

Open AccessArticle

Multi-Objective Optimization Design of Foamed Cement Mix Proportion Based on Response Surface Methodology

by Kailu Liu, Wanying Qu and Haoyang Zeng

Buildings 2025, 15(15), 2782; https://doi.org/10.3390/buildings15152782 - 6 Aug 2025

Viewed by 336

Abstract

Foam cement, as a building insulation material, encounters a major problem in practical application, which is the difficulty in achieving a balance between its strength and insulation performance. To achieve multi-objective optimization of foamed cement mix design, this study first determined the optimal [...] Read more.

Foam cement, as a building insulation material, encounters a major problem in practical application, which is the difficulty in achieving a balance between its strength and insulation performance. To achieve multi-objective optimization of foamed cement mix design, this study first determined the optimal ranges of nano-silica aerogel (NSA), foaming agent, and polypropylene (PP) fiber dosage through single-factor experiments. Then, response surface methodology (RSM) was employed to construct a quadratic polynomial regression model, systematically investigating the influence of different NSA contents, foaming agent contents, and PP fibers contents on the thermal conductivity and compressive strength of foamed cement. Finally, the optimal mix ratio was further predicted and experimentally validated. The results demonstrate that the regression model developed using RSM exhibits high accuracy and reliability. The correlation coefficients R² of the regression models established by the response surface method are 0.9756 and 0.9684, respectively, indicating good prediction accuracy. The optimized mix ratio was determined as follows: NSA content, 9.548%; foaming agent content, 0.533%; and PP fiber content, 0.1%. Under this mix, the model predicted a thermal conductivity of 0.123 W/(m·K) and a 28-day compressive strength of 1.081 MPa. Experimental verification confirmed that the errors between predicted and measured values for all performance indicators were within 5%, demonstrating the high reliability of the predictive model. This study provides support for the practical application of foam cement as a thermal insulation material in construction projects and offers guidance for optimizing its mixture composition. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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27 pages, 28656 KB

Open AccessArticle

Experimental Study and FEM Analysis on the Strengthening of Masonry Brick Walls Using Expanded Steel Plates and Shotcrete with and Without Glass Fiber Reinforcement

by Zeynep Yaman, Alper Cumhur, Elif Ağcakoca, Muhammet Zeki Özyurt, Muhammed Maraşlı, Mohammad Saber Sadid, Abdulsalam Akrami and Azizullah Rasuly

Buildings 2025, 15(15), 2781; https://doi.org/10.3390/buildings15152781 - 6 Aug 2025

Viewed by 593

Abstract

In this study, an effective strengthening method was investigated to improve the seismic performance of masonry brick walls. The strengthening method comprised the use of shotcrete, which was applied in both glass fiber-reinforced and unreinforced forms for steel plates and tie rods. Thirteen [...] Read more.

In this study, an effective strengthening method was investigated to improve the seismic performance of masonry brick walls. The strengthening method comprised the use of shotcrete, which was applied in both glass fiber-reinforced and unreinforced forms for steel plates and tie rods. Thirteen wall specimens constructed with vertical perforated masonry block bricks were tested under diagonal compression in accordance with ASTM E519 (2010). Reinforcement plates with different thicknesses (1.5 mm, 2 mm, and 3 mm) were anchored using 6 mm diameter tie rods. A specially designed steel frame and an experimental loading program with controlled deformation increments were employed to simulate the effects of reinforced concrete beam frame system on walls under the effect of diagonal loads caused by seismic loads. In addition, numerical simulations were conducted using three-dimensional finite element models in Abaqus Explicit software to validate the experimental results. The findings demonstrated that increasing the number of tie rods enhanced the shear strength and overall behavior of the walls. Steel plates effectively absorbed tensile stresses and limited crack propagation, while the fiber reinforcement in the shotcrete further improved wall strength and ductility. Overall, the proposed strengthening techniques provided significant improvements in the seismic resistance and energy absorption capacity of masonry walls, offering practical and reliable solutions to enhance the safety and durability of existing masonry structures. Full article

(This article belongs to the Special Issue Advanced Research on Concrete Materials in Construction)

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19 pages, 4225 KB

Open AccessArticle

Performance Optimization and Synergistic Mechanism of Ternary Blended Cementitious System Composed of Fly Ash, Slag, and Recycled Micro-Powder

by Rongfang Song, Qingnian Yang and Hang Song

Buildings 2025, 15(15), 2780; https://doi.org/10.3390/buildings15152780 - 6 Aug 2025

Viewed by 318

Abstract

The blended system of solid waste micro-powders is of great significance for the efficient utilization of recycled micro-powder. In this study, a ternary blended cementitious system composed of fly ash, slag, and recycled micro-powder was constructed, and its effects on the workability, mechanical [...] Read more.

The blended system of solid waste micro-powders is of great significance for the efficient utilization of recycled micro-powder. In this study, a ternary blended cementitious system composed of fly ash, slag, and recycled micro-powder was constructed, and its effects on the workability, mechanical properties, shrinkage performance, and microstructure of recycled mortar were systematically investigated. The experimental results show that with the increasing dosage of slag and recycled micro-powder (partially replacing cement and fly ash), the standard consistency water demand of the cementitious system decreases and the setting time is prolonged. When the replacement levels of recycled micro-powder and slag are both 10%, the 3-day, 7-day, and 28-day mechanical strengths of the mortar specimens are comparable to those of the reference group, with an increased flexural-to-compressive strength ratio and improved brittleness. SEM and mercury intrusion porosimetry (MIP) analyses revealed that systems incorporating low addition levels of recycled micro powder and slag powder exhibit calcium silicate hydrate (C-S-H) gel, acicular ettringite crystals, and a denser pore structure. However, at higher dosages (>10%), the porosity increases significantly and the pore structure deteriorates, resulting in reduced shrinkage performance. Overall, when the replacement rate of cement–fly ash by recycled micro-powder and slag is 10%, the ternary blended system exhibits optimal macroscopic performance and microstructure, providing a scientific basis for the resource utilization of solid waste. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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24 pages, 8377 KB

Open AccessArticle

Investigation of Wind Pressure Dynamics on Low-Rise Buildings in Sand-Laden Wind Environments

by Di Hu, Teng Zhang and Qiang Jin

Buildings 2025, 15(15), 2779; https://doi.org/10.3390/buildings15152779 - 6 Aug 2025

Viewed by 327

Abstract

To enhance the structural safety in wind-sand regions, this study employs the Euler-Lagrange numerical method to investigate the wind pressure characteristics of typical low-rise auxiliary buildings in a strong wind-blown sand environment. The results reveal that sand particle motion dissipates wind energy, leading [...] Read more.

To enhance the structural safety in wind-sand regions, this study employs the Euler-Lagrange numerical method to investigate the wind pressure characteristics of typical low-rise auxiliary buildings in a strong wind-blown sand environment. The results reveal that sand particle motion dissipates wind energy, leading to a slight reduction in average wind speed, while the increase in small-scale vortex energy enhances fluctuating wind speed. In the sand-laden wind field, the average wind pressure coefficient shows no significant change, whereas the fluctuating wind pressure coefficient increases markedly, particularly in the windward region of the building. Analysis of the skewness and kurtosis of wind pressure reveals that the non-Gaussian characteristics of wind pressure are amplified in the sand-laden wind, thereby elevating the risk of damage to the building envelope. Consequently, it is recommended that the design fluctuating wind load for envelopes and components of low-rise buildings in wind-sand regions be increased by 10% to enhance structural resilience. Full article

(This article belongs to the Section Building Structures)

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26 pages, 7199 KB

Open AccessArticle

Investigation of Fresh, Mechanical, and Durability Properties of Rubberized Fibre-Reinforced Concrete Containing Macro-Synthetic Fibres and Tyre Waste Rubber

by Nusrat Jahan Mim, Mizan Ahmed, Xihong Zhang, Faiz Shaikh, Ahmed Hamoda, Vipulkumar Ishvarbhai Patel and Aref A. Abadel

Buildings 2025, 15(15), 2778; https://doi.org/10.3390/buildings15152778 - 6 Aug 2025

Viewed by 387

Abstract

The growing disposal of used tyres and plastic waste in landfills poses a significant environmental challenge. This study investigates the potential of utilizing used tyre rubber and macro-synthetic fibres (MSFs) made from recycled plastics in fibre-reinforced rubberized concrete (RuFRC). Various percentages of tyre [...] Read more.

The growing disposal of used tyres and plastic waste in landfills poses a significant environmental challenge. This study investigates the potential of utilizing used tyre rubber and macro-synthetic fibres (MSFs) made from recycled plastics in fibre-reinforced rubberized concrete (RuFRC). Various percentages of tyre rubber shreds were used to replace coarse aggregates, calculated as 10%, 20%, and 30% of the volume of fine aggregates; fibre dosages (0%, 0.25%, 0.5%, 0.75%, and 1% by volume) were incorporated into the mix, and a series of physical, mechanical, and durability properties were evaluated. The results show that, as the fibre and rubber content increased, the slump of RuFRC decreased, with the lowest value obtained for concrete with 1% fibre and 30% rubber. The density of RuFRC decreases as the rubber percentage increases due to air voids and increased porosity caused by the rubber. The strength properties of RuFRC were found to decline with the increase in the rubber content, with mixes containing 30% rubber exhibiting reductions of about 60% in compressive strength, 27% in tensile strength, and 13% in flexural strength compared to the control specimen. Durability testing revealed that an increased rubber content led to higher water absorption, water penetration, and chloride ion permeability, with 30% rubber showing the highest values. However, lower rubber content (10%) and higher fibre dosages improved the durability characteristics, with water absorption reduced by up to 5% and shrinkage strains lowered by about 7%, indicating better compaction and bonding. These results indicate that RuFRC with moderate rubber and higher fibre content offers a promising balance between sustainability and performance. Full article

(This article belongs to the Section Building Materials, and Repair & Renovation)

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28 pages, 11045 KB

Open AccessArticle

Evaluating the Microclimatic Performance of Elevated Open Spaces for Outdoor Thermal Comfort in Cold Climate Zones

by Xuan Ma, Qian Luo, Fangxi Yan, Yibo Lei, Yuyang Lu, Haoyang Chen, Yuhuan Yang, Han Feng, Mengyuan Zhou, Hua Ding and Jingyuan Zhao

Buildings 2025, 15(15), 2777; https://doi.org/10.3390/buildings15152777 - 6 Aug 2025

Viewed by 282

Abstract

Improving outdoor thermal comfort is a critical objective in urban design, particularly in densely built urban environments. Elevated semi-open spaces—outdoor areas located beneath raised building structures—have been recognized for enhancing pedestrian comfort by improving airflow and shading. However, previous studies primarily focused on [...] Read more.

Improving outdoor thermal comfort is a critical objective in urban design, particularly in densely built urban environments. Elevated semi-open spaces—outdoor areas located beneath raised building structures—have been recognized for enhancing pedestrian comfort by improving airflow and shading. However, previous studies primarily focused on warm or temperate climates, leaving a significant research gap regarding their thermal performance in cold climate zones characterized by extreme seasonal variations. Specifically, few studies have investigated how these spaces perform under conditions typical of northern Chinese cities like Xi’an, which is explicitly classified within the Cold Climate Zone according to China’s national standard GB 50176-2016 and experiences both severe summer heat and cold winter conditions. To address this gap, we conducted field measurements and numerical simulations using the ENVI-met model (v5.0) to systematically evaluate the microclimatic performance of elevated ground-floor spaces in Xi’an. Key microclimatic parameters—including air temperature, mean radiant temperature, relative humidity, and wind velocity—were assessed during representative summer and winter conditions. Our findings indicate that the height of the elevated structure significantly affects outdoor thermal comfort, identifying an optimal elevated height range of 3.6–4.3 m to effectively balance summer cooling and winter sheltering needs. These results provide valuable design guidance for architects and planners aiming to enhance outdoor thermal environments in cold climate regions facing distinct seasonal extremes. Full article

(This article belongs to the Special Issue Buildings' Thermal Performance and Energy Efficiency for a Sustainable Construction)

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