Buildings

18 pages, 4603 KB

Open AccessArticle

Mechanism of Load Transfer and Deformation Coordination for a Novel Sliding-Type Connection Structure in Bridge Widening: Model Test and Numerical Investigations

by Wenqing Wu, Zheng Liu, Jiyang Liu, Dan Liu, Liang Chen and Wenwei Wang

Buildings 2025, 15(17), 3248; https://doi.org/10.3390/buildings15173248 - 8 Sep 2025

Viewed by 1127

Abstract

In lateral-joint-widening projects of multi-span continuous concrete box girder bridges, significant discrepancies in longitudinal shrinkage, creep deformation, and vertical displacement between the existing and newly added bridge sections can lead to stress concentration and subsequent concrete cracking. Notably, such incompatibility often results in [...] Read more.

In lateral-joint-widening projects of multi-span continuous concrete box girder bridges, significant discrepancies in longitudinal shrinkage, creep deformation, and vertical displacement between the existing and newly added bridge sections can lead to stress concentration and subsequent concrete cracking. Notably, such incompatibility often results in pronounced overall lateral bending deformation, which compromises the structural safety and service reliability of the widened bridge. To address these challenges, this study proposes a novel sliding-type transverse connection structure. This innovative connection enables the independent development of longitudinal shrinkage and creep deformation in the new bridge superstructure relative to the old one through a sliding mechanism, thereby effectively mitigating stress concentration and minimizing overall bending deformation caused by differential deformations. To validate the feasibility and elucidate the load transfer mechanism of the proposed structure, both scaled model tests and finite element simulations were conducted. The results indicate that the connection not only effectively coordinates longitudinal deformation differences and accommodates vertical deformation between the flange plates of the new and old bridges, but also ensures efficient transverse load transfer through shear force transmission. The structural behavior is primarily governed by shear stress distribution. These findings demonstrate that the sliding-type transverse connection significantly improves deformation compatibility in bridge widening applications, thereby enhancing the mechanical performance and safety reliability of the overall structure. Full article

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32 pages, 11997 KB

Open AccessArticle

Human Behavior Patterns in Meso-Scale Waterfront Public Spaces from a Visual Accessibility Perspective—A Case Study of Xiaoqinhuai Historic District, Yangzhou (China)

by Tianyu Li, Xiaoran Huang, Yuan Zhu and Jianguo Wang

Buildings 2025, 15(17), 3247; https://doi.org/10.3390/buildings15173247 - 8 Sep 2025

Viewed by 1377

Abstract

Understanding visitors’ outdoor activities in urban public spaces and their relationship with the physical environment is essential for improving the precision of public space design. This study, set in the context of Yangzhou, China, focuses on physical activity and other wellbeing behaviors in [...] Read more.

Understanding visitors’ outdoor activities in urban public spaces and their relationship with the physical environment is essential for improving the precision of public space design. This study, set in the context of Yangzhou, China, focuses on physical activity and other wellbeing behaviors in meso-scale waterfront public spaces, aiming to explore the characteristics of visitor behavior. A professional behavioral observation protocol was employed, combined with object detection and multi-object tracking algorithms, to systematically code visitor activities in the waterfront area. Subsequently, agent-based modeling (ABM) and three-dimensional isovist analysis (3D isovist) were introduced to construct a quantitative framework for assessing visual accessibility. The results reveal a significant positive correlation between facade Visual Exposure Time (seen from the observer) and isovist field area (seen from the object), providing strong evidence that visual accessibility is a primary causal driver of pedestrian behavior—independent of other causality. Based on these findings, this study proposes actionable design guidelines: “Prioritize small-scale, high-density waterfront building facade layouts to maximize visual efficiency” and “Leverage topographical variation along the waterfront by introducing cross-river visual corridors at intervals of ≤45 m”. The integrated analytical toolkit developed in this study—combining behavioral simulation with spatial–visual analysis—provides not only a theoretical foundation but also clear practical guidance for the fine-grained renewal and design of waterfront public spaces. Full article

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

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24 pages, 1242 KB

Open AccessReview

Perceptions of Multi-Story Wood Buildings: A Scoping Review

by Arati Paudel, Pipiet Larasatie, Sagar Godar Chhetri, Elena Rubino and Kevin Boston

Buildings 2025, 15(17), 3246; https://doi.org/10.3390/buildings15173246 - 8 Sep 2025

Viewed by 307

Abstract

The construction sector contributes significantly to global greenhouse gases, accounting for 39% of worldwide emissions. Multi-story wood buildings (MSWBs) present a sustainable alternative to traditional emissions-intensive construction materials like concrete and steel. However, only a few studies have investigated how potential customers perceive [...] Read more.

The construction sector contributes significantly to global greenhouse gases, accounting for 39% of worldwide emissions. Multi-story wood buildings (MSWBs) present a sustainable alternative to traditional emissions-intensive construction materials like concrete and steel. However, only a few studies have investigated how potential customers perceive MSWBs, which influences their acceptance and demand. This study uses a concept-driven scoping review to explore perceptions and concerns about living in MSWBs and to understand barriers to their adoption. Through a narrative synthesis of 20 peer-reviewed articles, this study uncovered five key themes: environmental sustainability, fire safety, human well-being, structural durability, and costs. These findings highlight opportunities and challenges for MSWBs’ market growth and inform future communication strategies to enhance public acceptance and promote sustainable construction and the built environment. Full article

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

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17 pages, 3779 KB

Open AccessArticle

How Environment Features Affect Children’s Emotions in Natural Playgrounds: A Context-Specific Case Study in China

by Zhishan Lin, Fei Yang and Donghui Yang

Buildings 2025, 15(17), 3245; https://doi.org/10.3390/buildings15173245 - 8 Sep 2025

Viewed by 407

Abstract

Natural playgrounds have garnered growing attention as supportive environments for children’s mental health. This study develops an analytical framework grounded in affordance theory and incorporates the Pleasure–Arousal–Dominance (PAD) model to examine the relationships between physical environmental features—and their combinations—in natural playgrounds and children’s [...] Read more.

Natural playgrounds have garnered growing attention as supportive environments for children’s mental health. This study develops an analytical framework grounded in affordance theory and incorporates the Pleasure–Arousal–Dominance (PAD) model to examine the relationships between physical environmental features—and their combinations—in natural playgrounds and children’s emotional perceptions. Using the Yunhu Natural Playground in Fuzhou, China, as a case study, we selected seven typical behavior setting units. Environmental features were assessed through UAV imagery and on-site observations, while PAD-based visual questionnaires were employed to collect emotional responses from 159 children. By applying correlation analysis, random forest, and regression tree models, this study identified key environmental predictors of children’s emotional responses and revealed heterogeneous mechanisms across the three emotional dimensions. The results indicated that seasonal flowering/fruiting plants, accessible lawns, and structured play facilities were critical in supporting children’s pleasure, arousal, and dominance. Specifically, pleasure was primarily associated with sensory enjoyment and contextual aesthetics, arousal favored open grassy areas, and dominance was linked to environments with clear structure and manipulability. Based on these findings, this study proposes a spatial configuration strategy characterized by “nature as foundation, play encouraged, and structure clarified” to promote the positive development of children’s multidimensional emotional experiences. This research contributes empirical evidence on the role of physical environmental features in supporting children’s play behaviors and expands the theoretical understanding of the “emotional effects” of green spaces. While the findings are exploratory and context-specific, they emphasize the critical role of the sensory–behavioral–emotional chain in shaping children’s well-being and provide theoretical and practical guidance for the design of emotionally supportive, child-friendly, natural play environments in schools, parks, and residential areas. Full article

(This article belongs to the Special Issue Art and Design for Healing and Wellness in the Built Environment)

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29 pages, 2256 KB

Open AccessArticle

Developing a Value Proposition Model for Construction 4.0 Decisions: A Futures Triangle Approach

by Makram Bou Hatoum and Hala Nassereddine

Buildings 2025, 15(17), 3244; https://doi.org/10.3390/buildings15173244 - 8 Sep 2025

Viewed by 389

Abstract

This paper introduces the Construction 4.0 Value Proposition Score (CVPS4.0)—a structured framework that enables Architecture, Engineering, and Construction (AEC) organizations to evaluate and communicate the value proposition of Construction 4.0 decisions. Grounded in the “Futures Triangle” theory, the study draws on existing research [...] Read more.

This paper introduces the Construction 4.0 Value Proposition Score (CVPS4.0)—a structured framework that enables Architecture, Engineering, and Construction (AEC) organizations to evaluate and communicate the value proposition of Construction 4.0 decisions. Grounded in the “Futures Triangle” theory, the study draws on existing research to identify three key dimensions: past barriers constraining AEC organizations, current trends driving industry change, and future transformations toward which the sector is evolving. In total, 45 barriers, 13 trends, and four transformations were identified as the foundation of the scoring framework. The model assesses how a decision influences each dimension, producing a composite score that reflects its overall value proposition. This score incorporates three considerations: the applicability of each factor to the organization, the degree of impact the decision has on it, and the relevance of the factor to the decision. The framework was validated through proof-of-concept with a subject-matter expert, who confirmed its value in supporting strategic, data-informed decision-making. As one of the first studies to evaluate the value proposition of Construction 4.0, this research offers both a practical decision-support tool and a consolidated reference on the forces shaping organizational change. CVPS4.0 provides AEC organizations with a proactive means to guide decisions, mitigate risks, and enhance long-term value creation. Full article

(This article belongs to the Special Issue The Digital Transformation of the Construction Industry: Current Practices, Challenges and Future Directions)

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23 pages, 5271 KB

Open AccessArticle

Rapid Regional Liquefaction Probability Assessment Based on Transfer Learning

by Jian-Yu Meng, Bao-Hua Shan and Da-Gang Lu

Buildings 2025, 15(17), 3243; https://doi.org/10.3390/buildings15173243 - 8 Sep 2025

Viewed by 372

Abstract

Earthquake-induced liquefaction poses significant risks to urban infrastructure, yet traditional regional assessment methods are hindered by sparse geotechnical data and high-cost exploration. Based on transfer learning, this study develops a rapid assessment procedure for regional probabilistic liquefaction, enabling efficient probabilistic liquefaction assessment. This [...] Read more.

Earthquake-induced liquefaction poses significant risks to urban infrastructure, yet traditional regional assessment methods are hindered by sparse geotechnical data and high-cost exploration. Based on transfer learning, this study develops a rapid assessment procedure for regional probabilistic liquefaction, enabling efficient probabilistic liquefaction assessment. This study demonstrates the feasibility of utilizing transfer learning to integrate abundant source domain data with readily available seismic information and post-earthquake observation data. A novel regional liquefaction probability index is also introduced. Both the proposed procedure and index are validated through their application to the 1999 Chi-Chi earthquake case, illustrating practical utility. Case results for Yuanlin City show that the assessment, which identifies the southeastern area as most liquefaction-prone and is consistent with both the index (highest values in this area) and post-earthquake field observations, validates the procedure’s effectiveness. A simplified calculation method for the index is also provided, ensuring strong practical applicability. Full article

(This article belongs to the Section Building Structures)

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44 pages, 16688 KB

Open AccessArticle

Comprehensive Design Process of CEB-Reinforced Masonry Panels for Earthquake and Hurricane-Resilient Houses

by Leandro Di Gregorio, Aníbal Costa, Alice Tavares, Hugo Rodrigues, Jorge Fonseca, Gustavo Guimarães, Assed Haddad, Fernando Danziger and Graziella Jannuzzi

Buildings 2025, 15(17), 3242; https://doi.org/10.3390/buildings15173242 - 8 Sep 2025

Viewed by 726

Abstract

Among the threats capable of causing disasters, earthquakes and hurricanes are those that most significantly impact the structures of buildings. This collaboration between UFRJ (Brazil) and UA (Portugal) aims to develop a house model that is both earthquake- and hurricane-resistant, within a specific [...] Read more.

Among the threats capable of causing disasters, earthquakes and hurricanes are those that most significantly impact the structures of buildings. This collaboration between UFRJ (Brazil) and UA (Portugal) aims to develop a house model that is both earthquake- and hurricane-resistant, within a specific range of magnitude to be determined, utilizing straightforward, affordable, and eco-friendly construction methods. SHS-Multirisk was developed under two phases. The first one carried out the design of the SHS-Multirisk 1.0 house model and the second phase comprised the preliminary conception of the SHS-Multirisk 2.0 architecture integrated with structural panels. This paper focuses on presenting the comprehensive research, development, and innovation (R&D&I) process of compressed earth block-reinforced masonry panels and the preliminary evaluation of their technical feasibility to be applied in SHS-Multirisk 2.0 house models. The steps of the process were explored in detail throughout process implementation, which revealed successive multi- and interdisciplinary challenges. Full article

(This article belongs to the Special Issue Reliability and Risk Assessment of Building Structures)

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18 pages, 4103 KB

Open AccessArticle

Field Evaluation of Thermal Comfort and Cooling Performance of Underfloor Air Distribution Systems in Stratified Spaces

by Yen-Chin Wu, Hsieh-Chih Hsu, Hsin-Yi Wang and Chen-Yu Pan

Buildings 2025, 15(17), 3241; https://doi.org/10.3390/buildings15173241 - 8 Sep 2025

Viewed by 375

Abstract

Indoor environments have received increasing attention in recent years, and achieving high-quality indoor conditions has become increasingly important. Underfloor air distribution (UFAD) systems have attracted significant interest due to their potential to improve ventilation efficiency, enhance thermal comfort, and reduce energy consumption. Compared [...] Read more.

Indoor environments have received increasing attention in recent years, and achieving high-quality indoor conditions has become increasingly important. Underfloor air distribution (UFAD) systems have attracted significant interest due to their potential to improve ventilation efficiency, enhance thermal comfort, and reduce energy consumption. Compared with overhead air distribution (OHAD) systems, UFAD not only offers better energy savings but also demonstrates improved thermal stratification performance. However, most previous studies have relied on numerical simulations to evaluate UFAD performance under specific system designs or scenarios. Few studies have conducted on-site measurements to investigate the combined effects of multiple air-conditioning settings, which are closely related to user control strategies. This study experimentally evaluated the cooling performance and thermal comfort of a UFAD system under different control configurations. By combining variations in airflow rate, temperature setpoints, and supply air distribution, a total of 12 test configurations were examined. The results indicate that configurations with lower temperature setpoints achieved the highest cooling performance. Most test settings produced neutral thermal conditions at heights between 120 and 180 cm, while areas at 60 cm or below were noticeably cooler. These findings provide practical guidance for users in controlling UFAD systems. Full article

(This article belongs to the Special Issue Building Thermal Environment: Improving Indoor Comfort by Optimizing Ventilation Systems)

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24 pages, 9167 KB

Open AccessArticle

Numerical Study: Substrate Thickness and Type of Roof Structure and Their Impact on the Thermal Behavior of Green Roofs

by Marek Chabada and Peter Juras

Buildings 2025, 15(17), 3240; https://doi.org/10.3390/buildings15173240 - 8 Sep 2025

Viewed by 282

Abstract

The aim of this article is to provide a parametric analysis of the thermal behavior of green roofs, focusing on the influence of the thickness of the vegetation substrate and the type of supporting structure. The simulation model is implemented on the roof [...] Read more.

The aim of this article is to provide a parametric analysis of the thermal behavior of green roofs, focusing on the influence of the thickness of the vegetation substrate and the type of supporting structure. The simulation model is implemented on the roof structure of an industrial hall in Dubnica nad Váhom, Slovakia, which was created and successfully validated based on real measurements of temperatures and climatic conditions during eight days in September 2023. After validating the model, a series of simulations of three structural variants was performed over three days in the summer. The results demonstrated that the greatest impact on reducing temperature fluctuations was achieved by increasing the thickness of the vegetation substrate (variant V2), which contributed to a reduction in heat flows fluctuations of up to 82% and caused a favorable phase shift in maximum temperatures. The introduction of a reinforced concrete supporting structure (variant V1) brought a partial improvement in the lower layers, while the combined variant (V3) demonstrated the best results—stabilization of temperatures and heat flows throughout the structure, eliminating overheating and cooling of the interior, and overall improvement in the thermal balance of the roof system. The results point to the high potential of green roofs in improving the thermal properties of buildings in summer conditions. Full article

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

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37 pages, 7717 KB

Open AccessArticle

Synergising Circular Economy Principles in Industrialised Construction: Fuzzy Synthetic Evaluation of Key Constructs of Design for Circular Manufacturing and Assembly (DfCMA)

by Kaveesha Gihani Dewagoda, Ji Chen, Mohan M. Kumaraswamy and S. Thomas Ng

Buildings 2025, 15(17), 3239; https://doi.org/10.3390/buildings15173239 - 8 Sep 2025

Viewed by 319

Abstract

Rapid urbanisation and population growth call for more Industrialised Construction (IC) as a swifter, safer, higher-quality and affordable means of delivering housing and infrastructure. Meanwhile, rising global temperatures and extreme weather patterns call for immediate action to combat environmental degradation. The Building Construction [...] Read more.

Rapid urbanisation and population growth call for more Industrialised Construction (IC) as a swifter, safer, higher-quality and affordable means of delivering housing and infrastructure. Meanwhile, rising global temperatures and extreme weather patterns call for immediate action to combat environmental degradation. The Building Construction Industry (BCI) is a leading contributor to global resource extraction and waste generation, posing a significant threat to our environment and planet. Design for Circular Manufacturing and Assembly (DfCMA) is an overarching design framework that synergises circularity (Design for Circularity (DfC)) and modularity (Design for Manufacturing and Assembly (DfMA)) by enhancing their shared values. This study explores the functional apparatus of DfCMA by identifying 21 DfMA constructs and 20 DfC constructs in the BCI through a rigorous literature review, first analysed descriptively, followed by Exploratory Factor Analysis (EFA) and Fuzzy Synthetic Evaluation (FSE) of the initial findings from a suitably focused questionnaire survey. The study findings confirm the significance of applying the 41 constructs above in advancing the concept of DfCMA in the BCI. This study thus adds value to research and practice, exploring the underlying mechanism of this novel DfCMA concept, which synergises two imperatives, promoting a Circular Economy (CE) and DfMA principles and practices in IC. Full article

(This article belongs to the Special Issue A Circular Economy Paradigm for Construction Waste Management)

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28 pages, 3719 KB

Open AccessArticle

Evaluating Algorithm Efficiency in Large-Scale Dome Truss Optimization Under Frequency Constraints

by Ibrahim Behram Ugur

Buildings 2025, 15(17), 3238; https://doi.org/10.3390/buildings15173238 - 8 Sep 2025

Viewed by 559

Abstract

Incorporating frequency constraints into the optimum design of large-scale truss dome structures is crucial for maintaining seismic resilience, as the natural frequencies must remain within specified ranges. In this work, seven metaheuristic algorithms—including three variants of the Fitness–Distance–Balance-based Adaptive Guided Differential Evolution (FDB-AGDE), [...] Read more.

Incorporating frequency constraints into the optimum design of large-scale truss dome structures is crucial for maintaining seismic resilience, as the natural frequencies must remain within specified ranges. In this work, seven metaheuristic algorithms—including three variants of the Fitness–Distance–Balance-based Adaptive Guided Differential Evolution (FDB-AGDE), the Cheetah Optimizer (CO), the Bonobo Optimizer (BO), the Flood Algorithm (FLA), and the Lung Performance Optimization (LPO) are applied to solve high-dimensional truss sizing problems under strict frequency limitations. Their convergence characteristics and solution quality are systematically compared across multiple dome configurations. Besides traditional measures of computational efficiency and final weight minimization, a suite of statistical analyses is conducted: the Wilcoxon rank-sum test to assess pairwise performance significance, the Friedman test to establish overall rank ordering, and Cohen’s test to quantify effect sizes. The results reveal that LPO, BO, CO, and the first variant of FDB-AGDE consistently produce lighter feasible designs with lower variability, whereas FLA and other variants of FDB-AGDE exhibit heavier structures or higher dispersion. The findings underscore the value of robust, well-tuned metaheuristics and rigorous statistical evaluation in structural optimization, offering clear guidance for seismic-focused designers seeking both lightweight solutions and reliable performance across repeated runs. Full article

(This article belongs to the Section Building Structures)

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20 pages, 583 KB

Open AccessArticle

The Influence Mechanism of Organizational Context and Tacit Knowledge Sharing on Innovation Performance in Mega Projects

by Hongsheng Kan, Yujuan Li and Xue Li

Buildings 2025, 15(17), 3237; https://doi.org/10.3390/buildings15173237 - 8 Sep 2025

Viewed by 429

Abstract

Improving the innovation performance of mega projects has become a central concern in both engineering project management theory and practice. Organizational structure and culture are key contextual factors that can facilitate tacit knowledge sharing across organizations, thereby enhancing innovation outcomes. Based on the [...] Read more.

Improving the innovation performance of mega projects has become a central concern in both engineering project management theory and practice. Organizational structure and culture are key contextual factors that can facilitate tacit knowledge sharing across organizations, thereby enhancing innovation outcomes. Based on the data of 243 questionnaires, this paper systematically analyzes the influence mechanism of organizational context factors on innovation performance by using the structural equation model (SEM). The results show that organizational structure exerts a significant negative effect on both tacit knowledge sharing and innovation performance. Among the dimensions of organizational culture, trust climate and organizational support have significant positive effects on both tacit knowledge sharing and innovation performance. While the level of cooperation enhances tacit knowledge sharing, its direct impact on innovation performance is not statistically significant. Furthermore, in the organizational context and innovation performance, tacit knowledge sharing also plays different mediating roles. The results can provide theoretical guidance for mega projects to break through the obstacle of technological transformation and enhance innovation efficiency. Full article

(This article belongs to the Special Issue Innovation in Construction and Project Management: Digital Technologies, Intelligent Systems, and Sustainable Solutions)

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21 pages, 29226 KB

Open AccessArticle

New Buildings of the Gdańsk University of Technology Campus as an Example of Synergy of Contemporary Technologies and Cultural Heritage

by Antoni Taraszkiewicz

Buildings 2025, 15(17), 3236; https://doi.org/10.3390/buildings15173236 - 8 Sep 2025

Viewed by 443

Abstract

This article presents an analysis of the architectural integration of two new buildings implemented on the Gdańsk University of Technology campus (Poland) as a case study of combining contemporary technologies with cultural continuity. The buildings, designed by the author of the article, who [...] Read more.

This article presents an analysis of the architectural integration of two new buildings implemented on the Gdańsk University of Technology campus (Poland) as a case study of combining contemporary technologies with cultural continuity. The buildings, designed by the author of the article, who is the main designer, are a conscious response to the historical urban and architectural context of the campus, the development of which started at the beginning of the 20th century in the style of Dutch Neo-Renaissance. The new buildings refer to the architectural heritage of the university through their scale and colors, but their form, details and applied technological solutions clearly reflect modernity. A particularly important element of their modern character is the implementation of advanced pro-ecological systems for obtaining energy from renewable sources (RES), which fits into the current climate challenges and the role of the technical university as a promoter of sustainable development. The article discusses how architecture, materials and modern building systems were used to create a dialogue between tradition and innovation. The analysis is based on design documentation and planning conditions, and its background is a broader discourse on culturally sustainable architecture. Conscious of other, more conservative views, the author puts forward the thesis that cultural continuity does not require stylistic imitation, but conscious, contextual reinterpretation. The results of the article enrich the debate on the development of academic campuses, heritage-responsible design and the role of the architect in shaping a space that connects the future with the past. The main research contribution of the article is the presentation of an original method of designing architectural objects that integrates advanced pro-ecological technologies with a contextual reinterpretation of architectural heritage, which constitutes a new perspective in the discussion on culturally sustainable architecture. Full article

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

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27 pages, 7352 KB

Open AccessArticle

Indoor Microclimate Monitoring in Heritage Buildings: The Bologna University Library Case Study

by Andrea Boeri, Kristian Fabbri, Danila Longo and Rossella Roversi

Buildings 2025, 15(17), 3235; https://doi.org/10.3390/buildings15173235 - 8 Sep 2025

Viewed by 513

Abstract

The indoor microclimate conditions of historical libraries play a pivotal role in ensuring the long-term preservation of their valuable collections, while also influencing the comfort and well-being of staff and visitors. These two objectives may be in contrast, as proved in extensive literature. [...] Read more.

The indoor microclimate conditions of historical libraries play a pivotal role in ensuring the long-term preservation of their valuable collections, while also influencing the comfort and well-being of staff and visitors. These two objectives may be in contrast, as proved in extensive literature. Microclimate monitoring is essential to evaluate which factors could expose the content of the library to a risk of damage and to design prevention measures. This paper presents the monitoring project, the systems and methodology, and the initial results of an experimental study on the indoor microclimate conditions of the University Library of Bologna (BUL), a very relevant cultural heritage building in the historic city center. The overall objective of the monitoring project is to gain knowledge of the specific microclimate conditions and the historical climate of the three main rooms of the BUL to define the right balance between the needs of conservation and the thermal comfort of staff, users, and visitors. The paper focuses on the short-term indoor monitoring assessment, carried out in the initial phase of the monitoring campaign. This phase, rarely addressed in the literature, is crucial because it enables the collection of results that can guide and orient the entire long-term monitoring campaign. The research results produced so far demonstrate the validity of the methodological approach and the monitoring framework, as well as the reliability of the related data. Moreover, they offer insights that can support the forthcoming inclusion of the BUL in a broader museum system. Full article

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

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21 pages, 4836 KB

Open AccessReview

Novel Methodological Approach to Developing Scaled-Down Concrete Material for Structural Applications: Experimental Validation Using Froude Scaling

by Abdelmoneim El Naggar, Ahmed Soliman, Maged A. Youssef and Hany El Naggar

Buildings 2025, 15(17), 3234; https://doi.org/10.3390/buildings15173234 - 8 Sep 2025

Viewed by 452

Abstract

Full-scale structural experiments significantly contribute to understanding reinforced concrete (RC) behavior but are often constrained by high costs, extensive time requirements, and practical spatial limitations. Alternatively, small-scale physical models offer a feasible solution, though accurately replicating nonlinear material behavior under load at reduced [...] Read more.

Full-scale structural experiments significantly contribute to understanding reinforced concrete (RC) behavior but are often constrained by high costs, extensive time requirements, and practical spatial limitations. Alternatively, small-scale physical models offer a feasible solution, though accurately replicating nonlinear material behavior under load at reduced scales remains challenging. This research addresses these challenges by introducing a methodological approach to developing a novel scaled-down concrete material to emulate full-scale structural behavior. The developed material strictly adheres to Froude similitude criteria, ensuring an accurate representation of gravitational effects without requiring artificially induced gravity, such as centrifuge testing. Experimental validation demonstrates that this material model successfully replicates critical mechanical properties of full-scale concrete, with less than 2% variance observed in compressive strength, strain characteristics, and failure modes. Further validation through comparative testing of scaled-down and corresponding full-scale RC beams confirms the material’s capability to precisely capture structural responses. Consequently, the proposed scaled-down concrete model offers a reliable, economical, and effective approach to evaluating structural performance, overcoming traditional limitations associated with full-scale structural experimentation. Full article

(This article belongs to the Collection Buildings for the 21st Century)

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22 pages, 6770 KB

Open AccessArticle

Seismic Response Estimation of Multi-Story Structures Equipped with a Cost-Effective Earthquake Protection System

by Ryuta Enokida and Cem Yenidogan

Buildings 2025, 15(17), 3233; https://doi.org/10.3390/buildings15173233 - 8 Sep 2025

Viewed by 426

Abstract

This study presents a new method for estimating the seismic responses of multi-story structures equipped with a cost-effective earthquake protection system. This system comprises a graphite lubrication interface, targeting a friction coefficient of approximately 0.2, and a feasible restoring force mechanism to suppress [...] Read more.

This study presents a new method for estimating the seismic responses of multi-story structures equipped with a cost-effective earthquake protection system. This system comprises a graphite lubrication interface, targeting a friction coefficient of approximately 0.2, and a feasible restoring force mechanism to suppress residual displacements. It utilizes the concept of sliding systems through conventional and affordable construction materials although it acts like a fixed-based structure until exceeding the threshold level. This multi-story estimation procedure is an extension of the recently developed procedure for estimating the shear coefficient of a single-story sliding structure with a restoring force mechanism. In the new estimation procedure, a multi-story superstructure is firstly regarded as a single-story superstructure to determine the shear coefficient. Then, the shear coefficient is distributed to each story through floor distribution coefficients considering the mass ratios. The contribution of ground motion intensity is also incorporated into the new form for improving accuracy. For this examination, incremental dynamic analyses (IDAs) are performed for three and six-story free-standing structures, both with and without a restoring force capability. The results clarify the reliability of the new estimation, which matched the IDA results within the ±20% error. The improvement in accuracy achieved by incorporating ground motion intensity is also clarified. The multi-story estimation with the improvement can reasonably estimate the seismic response of sliding structures, without dynamic analysis, solely based on structural properties. This greatly benefits the design process. Furthermore, the IDA results clarified the significant benefits of multi-story sliding structures employing graphite lubrication and properly designed restoring force mechanisms in reducing structural damage and suppressing residual sliding displacements. Full article

(This article belongs to the Special Issue Innovative Solutions for Enhancing Seismic Resilience of Buildings)

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41 pages, 13531 KB

Open AccessArticle

Integrated Hydrogen in Buildings: Energy Performance Comparisons of Green Hydrogen Solutions in the Built Environment

by Hamida Kurniawati, Siebe Broersma, Laure Itard and Saleh Mohammadi

Buildings 2025, 15(17), 3232; https://doi.org/10.3390/buildings15173232 - 8 Sep 2025

Viewed by 466

Abstract

This study investigates the integration of green hydrogen into building energy systems using local solar power, with the electricity grid serving as a backup plan. A comprehensive bottom-up analysis compares six energy system configurations: the natural gas grid boiler system, all-electric heat pump [...] Read more.

This study investigates the integration of green hydrogen into building energy systems using local solar power, with the electricity grid serving as a backup plan. A comprehensive bottom-up analysis compares six energy system configurations: the natural gas grid boiler system, all-electric heat pump system, natural gas and hydrogen blended system, hydrogen microgrid boiler system, cogeneration hydrogen fuel cell system, and hybrid hydrogen heat pump system. Energy efficiency evaluations were conducted for 25 homes within one block in a neighborhood across five typological house stocks located in Stoke-on-Trent, UK. This research was modeled using a spreadsheet-based approach. The results highlight that while the all-electric heat pump system still demonstrates the highest energy efficiency with the lowest consumption, the hybrid hydrogen heat pump system emerges as the most efficient hydrogen-based solution. Further optimization, through the implementation of a peak-shaving strategy, shows promise in enhancing system performance. In this approach, hybrid hydrogen serves as a heating source during peak demand hours (evenings and cold seasons), complemented by a solar energy powered heat pump during summer and daytime. An hourly operational configuration is recommended to ensure consistent performance and sustainability. This study focuses on energy performance, excluding cost-effectiveness analysis. Therefore, the cost of the energy is not taken into consideration, requiring further development for future research in these areas. Full article

(This article belongs to the Special Issue Potential Use of Green Hydrogen in the Built Environment)

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19 pages, 6539 KB

Open AccessArticle

Evaluating the Effects of Vegetation on Daylight Performance: A Simulation-Based Study of Government School Buildings in the Hot–Humid Climate of Chennai, India

by Jeyaradha Jayaram and Lakshmi Sundaram

Buildings 2025, 15(17), 3231; https://doi.org/10.3390/buildings15173231 - 8 Sep 2025

Viewed by 499

Abstract

This study examines the influence of vegetation on indoor daylight performance in school buildings located in the hot–humid climate of Chennai, India. With increasing urban development leading to the cutting or relocation of trees, their role in modulating interior daylight conditions has become [...] Read more.

This study examines the influence of vegetation on indoor daylight performance in school buildings located in the hot–humid climate of Chennai, India. With increasing urban development leading to the cutting or relocation of trees, their role in modulating interior daylight conditions has become critically relevant but remains underexplored in the literature. Recognizing a significant research gap in this area, this study employed a simulation-based approach using DesignBuilder 7.4 software. A government school in South Chennai, India, was chosen for this study. A total of 208 scenarios were generated by varying the window-to-wall ratio (WWR), facade orientation, floor level, and tree presence. Daylight performance was evaluated using spatial daylight autonomy (sDA), annual sunlight exposure (ASE), and useful daylight illuminance (UDI), based on IES LM-83-12 and LEED v4 standards. Simulation results showed that a 20% window-to-wall ratio (WWR) failed to meet daylight standards, while a 30–40% WWR with shading consistently performed well. Trees significantly improved daylight metrics, like sDA, UDI, and ASE, more so than orientation or floor level. This study urges regulatory mandates for climate-resilient schools, emphasizing fenestration and landscape integration. Full article

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

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21 pages, 8396 KB

Open AccessArticle

Assessment of Steel-Framed Subassemblies with Extended Reverse Channel Connections Under Falling Debris Impact

by Hao Wang, Lijie Zhao, Qi Zhang, Jianshuo Wang, Yongping Xie and Marcin Gryniewicz

Buildings 2025, 15(17), 3230; https://doi.org/10.3390/buildings15173230 - 8 Sep 2025

Viewed by 410

Abstract

Progressive collapse of building structures induced by accidental extreme loads has garnered significant attention. This study aimed to assess the impact resistance of steel-framed subassemblies with extended reverse channel connections under falling debris impact. It also sought to provide technical support for anti-collapse [...] Read more.

Progressive collapse of building structures induced by accidental extreme loads has garnered significant attention. This study aimed to assess the impact resistance of steel-framed subassemblies with extended reverse channel connections under falling debris impact. It also sought to provide technical support for anti-collapse design. Drop-hammer impact tests were conducted to obtain baseline data. A validated finite element model using ANSYS/LS-DYNA was employed for the parametric analyses. The key parameters investigated included the impact location (mid-span vs. beam end), falling height of the impactor, and span-to-depth ratio of steel beams, with a focus on the impact resistance. The results reveal that the impact resistance depends on both the peak load capacity and the deformation capacity. The mid-span impacts exhibited higher resistance at falling heights ≥ 1.0 m due to greater plastic deformation. In contrast, the beam-end impacts performed better when the falling heights were ≤0.5 m. The impact resistance decreased with an increasing falling height. The reduction ratios exceeded the theoretical values due to the post-impact gravitational energy input. Smaller SDRs enhanced the peak resistance under both impact scenarios, with more pronounced effects in the mid-span cases. Catenary action significantly improved the mid-span impact resistance (19.3–66.7%). However, it contributed minimally to the beam-end impact resistance (0.61–1.09%), where shear action dominated. These findings offer critical technical support for optimizing steel structure designs to resist falling debris impact and enhance overall structural robustness. Full article

(This article belongs to the Special Issue Advances in Modern Structural Engineering: From Materials to Building Structures)

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19 pages, 3391 KB

Open AccessArticle

Ancient Solutions for Modern Challenges: Structural Analysis of Roman Ventilated Facade Systems

by Armando La Scala

Buildings 2025, 15(17), 3229; https://doi.org/10.3390/buildings15173229 - 8 Sep 2025

Viewed by 397

Abstract

The rising need for sustainable building technologies and passive ventilation strategies has sparked renewed research interest in traditional building practices. In this regard, Roman thermal buildings are notable for their incorporation of sophisticated ventilated facade systems. Nevertheless, the structural performance of these buildings [...] Read more.

The rising need for sustainable building technologies and passive ventilation strategies has sparked renewed research interest in traditional building practices. In this regard, Roman thermal buildings are notable for their incorporation of sophisticated ventilated facade systems. Nevertheless, the structural performance of these buildings remains poorly understood. This study presents a numerical analysis of Roman ventilated facade systems, focusing on the Forum Women’s Thermal Baths in Pompeii. A nonlinear finite element model is developed in Straus7 to examine the dynamic response and establish baseline dynamic properties essential for future structural performance assessments. Modal analysis identified characteristic frequencies related to the horizontal translation modes. The numerical model will give insight into the load transfer pattern between the individual tegulae and the supporting structures. The results will provide a quantitative database on dynamic characteristics for these traditional systems and set out a verified computational procedure applicable in the fields of heritage conservation and current design practice. The current study combines archaeology and engineering in order to obtain valuable insights into ventilation strategies still applicable in the design of sustainable buildings. Full article

(This article belongs to the Special Issue Analysis, Conservation, and Refurbishment Methods of Heritage Architecture Based on Modern Technology)

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22 pages, 19940 KB

Open AccessArticle

Augmented Reality in Review Processes for Building Authorities: A Case Study in Vienna

by Alexander Gerger, Harald Urban, Konstantin Höbart, Gabriel Pelikan and Christian Schranz

Buildings 2025, 15(17), 3228; https://doi.org/10.3390/buildings15173228 - 8 Sep 2025

Viewed by 607

Abstract

The digital transformation of the construction industry is still lagging due to its incomplete implementation throughout the entire building lifecycle. One stakeholder in particular has been largely overlooked thus far: public administration. This study explores the potential integration of augmented reality (AR) into [...] Read more.

The digital transformation of the construction industry is still lagging due to its incomplete implementation throughout the entire building lifecycle. One stakeholder in particular has been largely overlooked thus far: public administration. This study explores the potential integration of augmented reality (AR) into the processes of building authorities, with a particular focus on the review part of the permissions process, taking the City of Vienna as an example. As part of the EU-funded BRISE-Vienna project, an AR platform was developed and tested and an AR application was designed to enhance the transparency, stakeholder communication, and efficiency throughout the process. This study compares the proposed AR-based review process with the traditional plan-based approach, assessing both hard and soft factors. To this end, the durations of the individual process steps were measured, with a particular focus on the time spent by the officers (as a hard factor). In addition, qualitative surveys were conducted to gather the subjective impressions of the test participants (as soft factors). The key findings were a reduction in the officers’ workloads and an improvement in spatial understanding. While the overall review time remained similar, the use of AR reduced officers’ workload by over 40%. Additionally, the test participants stated that AR improved their spatial understanding and alleviated the time pressure within the process. This case study demonstrates the potential of AR in the permissions process and could serve as a model for other cities and countries. Full article

(This article belongs to the Special Issue The Digital Transformation of the Construction Industry: Current Practices, Challenges and Future Directions)

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23 pages, 7556 KB

Open AccessArticle

On-Site Monitoring and a Hybrid Prediction Method for Noise Impact on Sensitive Buildings near Urban Rail Transit

by Yanmei Cao, Yefan Geng, Jianguo Chen and Jiangchuan Ni

Buildings 2025, 15(17), 3227; https://doi.org/10.3390/buildings15173227 - 7 Sep 2025

Viewed by 748

Abstract

The environmental noise impact on sensitive buildings and residents, generated by urban rail transit systems, has attracted increasing attention from the public and various levels of management. Owing to the diversity of building types and the complexity of noise propagation paths, the accurate [...] Read more.

The environmental noise impact on sensitive buildings and residents, generated by urban rail transit systems, has attracted increasing attention from the public and various levels of management. Owing to the diversity of building types and the complexity of noise propagation paths, the accurate prediction of noise levels adjacent to structures through traditional experimental or empirical formula-based methods is challenging. In this paper, on-site multi-dimensional noise monitoring of the noise source affecting the sensitive buildings was first carried out, and a hybrid prediction method combining normative formulas, numerical simulations, and experimental research is proposed and validated. This approach effectively addresses the shortcomings of traditional prediction methods in terms of source strength determination, propagation path distribution, and accuracy of results. The results show that, while predicting or assessing the noise impact on sensitive buildings and interior residents, it is important to properly consider the impact of background noise (such as road traffic) as well as vibration radiation noise of bridge structures. The predicted results obtained by using this method closely match the measured results, with errors controlled within 3 dB(A). The noise prediction error in front of buildings is controlled within 2 dB(A), fully meeting the requirements for environmental noise assessment. Full article

(This article belongs to the Special Issue Advanced Prediction and Mitigation of Building Vibrations and Noise: Integrating Safety and Sustainability)

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14 pages, 3176 KB

Open AccessArticle

Acoustic Emission Assisted Inspection of Punching Shear Failure in Reinforced Concrete Slab–Column Structures

by Xinchen Zhang, Zhihong Yang and Guogang Ying

Buildings 2025, 15(17), 3226; https://doi.org/10.3390/buildings15173226 - 7 Sep 2025

Viewed by 624

Abstract

Slab–column structures are susceptible to sudden punching shear failure at connections due to the absence of traditional beam support, prompting the need for effective damage monitoring. This study employs an acoustic emission (AE) technique to investigate the failure process of reinforced concrete slab–column [...] Read more.

Slab–column structures are susceptible to sudden punching shear failure at connections due to the absence of traditional beam support, prompting the need for effective damage monitoring. This study employs an acoustic emission (AE) technique to investigate the failure process of reinforced concrete slab–column specimens, analyzing basic AE parameters (hits, amplitude, energy), improved b-value (Ib-value), and RA–AF correlation, while introducing a Gaussian Mixture Model (GMM) to establish a unified index integrating crack type identification and energy information. Experimental results show that AE parameters can effectively track different stages of crack development, with Ib-value reflecting the transition from micro-crack to macro-crack growth. The correlation between AE energy and structural strain energy enables quantitative damage assessment, while RA–AF analysis and GMM clustering reveal the shift from bending-dominated to shear-dominated failure modes. This study provides a comprehensive framework for real-time damage evaluation and failure mode prediction in slab–column structures, demonstrating that AE-based multi-parameter analysis and data-driven clustering methods can characterize damage evolution and improve the reliability of structural health monitoring. Full article

(This article belongs to the Special Issue The Application of Intelligence Techniques in Construction Materials)

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23 pages, 12573 KB

Open AccessArticle

SMA-Activated Double-Stage Yielding BRB: Experimental and FEM Insights

by Huijie Huang, Jiyang Wang, Dong Yao, Pinghuai Zhou and Senlin Zhao

Buildings 2025, 15(17), 3225; https://doi.org/10.3390/buildings15173225 - 7 Sep 2025

Viewed by 584

Abstract

To address the limitations of traditional buckling-restrained braces (BRB), which feature a single-stage yielding and inadequate energy dissipation under small earthquakes, this study proposes a novel double-stage yielding buckling-restrained brace (DSY-BRB). The proposed design integrates a sliding friction damper with shape memory alloy [...] Read more.

To address the limitations of traditional buckling-restrained braces (BRB), which feature a single-stage yielding and inadequate energy dissipation under small earthquakes, this study proposes a novel double-stage yielding buckling-restrained brace (DSY-BRB). The proposed design integrates a sliding friction damper with shape memory alloy (SMA) bolts and conventional BRB components, enabling effective energy dissipation at small deformations and adaptive performance across varying displacement amplitudes compared with traditional BRBs. Leveraging SMA superelasticity, the DSY-BRB also exhibits self-centering capability that distinguishes it from prior DSY-BRB configurations. Experimental investigations were conducted on DSY-BRB specimens with varying core plate widths under cyclic quasi-static loading to evaluate hysteresis behavior, energy dissipation capacity, and self-centering performance. Results demonstrate that DSY-BRBs exhibit symmetric flag-shaped hysteresis curves with enhanced energy dissipation and excellent self-centering capabilities, achieving minimal residual deformation compared to traditional BRBs. Complementary finite element modeling with parametric analysis was performed to establish design guidelines for optimal double-stage buckling behavior. The findings reveal critical stiffness ratio requirements between BRB and SMA bolt-based friction damper components, providing valuable design criteria for engineering applications. This hybrid approach offers significant advantages in seismic energy dissipation and structural resilience compared to existing DSY-BRB systems. Full article

(This article belongs to the Section Building Structures)

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25 pages, 6220 KB

Open AccessArticle

Youth Visual Engagement and Cultural Perception of Historic District Interfaces: The Case of Kuanzhai Alley, Chengdu

by Yuhan Zhang, Nina Mo and Jiakang Liang

Buildings 2025, 15(17), 3224; https://doi.org/10.3390/buildings15173224 - 7 Sep 2025

Viewed by 496

Abstract

Historic districts are key urban spaces that convey cultural heritage and support tourism and social interaction. As the spatial interface shapes form and perception, this study explores youth-oriented visual behaviour and cognitive preferences regarding historic street interfaces. Using Kuan-Narrow Alley in Chengdu as [...] Read more.

Historic districts are key urban spaces that convey cultural heritage and support tourism and social interaction. As the spatial interface shapes form and perception, this study explores youth-oriented visual behaviour and cognitive preferences regarding historic street interfaces. Using Kuan-Narrow Alley in Chengdu as a case study, we analysed eye-tracking data to assess visual engagement with interface elements. Architectural components received the highest attention for Total Fixation Duration, Fixation Count, and Visit Count, while commercial elements yielded a longer Average Fixation Duration. A multiple linear regression model identified Historical Linguistic Landscape (β = 1.088), Street Permeability (β = 0.401), and Street Width-to-Height Ratio (β = 0.178) as significant predictors of perceived usability, with Historical Linguistic Landscape proving most influential. These findings underscore the value of preserving cultural significance in streetscape morphology and provide theoretical and practical insights from a youth-centric perspective. By integrating eye-tracking with morphological analysis, the study offers a novel approach to understanding visual perceptions in historic districts. Despite limitations in sample size and scope, the study provides solid insights, with future research needed to broaden contexts for greater generalisability. Full article

(This article belongs to the Special Issue Built Heritage Conservation in the Twenty-First Century: 2nd Edition)

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18 pages, 3483 KB

Open AccessArticle

Research on the Optimization of Healthy Living Environments in Liyuan Block Empowered by CFD Technology: A Case Study of the Liyuan Block in Dabaodao, Qingdao

by Huiying Zhang, Hui Feng, Xiaolin Zang and Ang Sha

Buildings 2025, 15(17), 3223; https://doi.org/10.3390/buildings15173223 - 7 Sep 2025

Viewed by 424

Abstract

In the process of revitalizing historic districts, creating a healthy living environment requires a focus on the microclimate comfort of historic districts. Microclimate comfort refers to the comprehensive physiological perception and psychological satisfaction of climate elements such as heat, wind, and humidity under [...] Read more.

In the process of revitalizing historic districts, creating a healthy living environment requires a focus on the microclimate comfort of historic districts. Microclimate comfort refers to the comprehensive physiological perception and psychological satisfaction of climate elements such as heat, wind, and humidity under specific local environmental conditions, typically within a spatial range of horizontal scale < 100 m and vertical scale < 10 m. Among these, wind environment quality, as a key factor influencing pedestrian health experiences and cultural tourism appeal, holds particular research value. This study takes the Dabao Island Courtyard District in Qingdao as its subject, employing computational fluid dynamics (CFD) simulation methods from the artificial intelligence (AI) technology framework for modeling. CFD is a numerical method based on computer simulation, which solves fluid control equations (such as the Navier–Stokes equations) through iterative optimization to achieve high-fidelity simulation of physical environments such as airflow, turbulence, and heat transfer. A three-dimensional geometric model of the Dabao Island courtyard district was established, and boundary conditions were set based on local meteorological data. Numerical simulations were conducted to analyze the wind environment before and after the renovation of different layouts, functional spaces, and spatial scales (individual courtyards, clustered courtyards, and surrounding neighborhoods) of the courtyard district. The results indicate that factors such as building layout, street orientation, and renovation strategies significantly influence the wind environment of the Dabao Island neighborhood courtyards, thereby affecting residents’ perceptions of wind comfort. For example, unreasonable building layouts can lead to excessive local wind speeds or vortex phenomena, reducing wind comfort, whereas reasonable renovation and update strategies can facilitate the introduction of wind corridors into the historical courtyard buildings, improving wind environment quality. This study contributes to better protection and utilization of traditional neighborhoods during urban renewal processes, creating a more comfortable wind environment for residents, providing scientific decision-making support for the renovation of historical neighborhoods under the Healthy China strategy, and offering methodological references for wind environment research in other similar traditional neighborhoods. Full article

(This article belongs to the Special Issue Recent Advances in Intelligent Applications of Well-Being Spaces Design and Engineering)

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23 pages, 13382 KB

Open AccessArticle

Effects of Ion-Regulated Mechanisms on Calcite Precipitation in the Enzyme-Induced Carbonate Precipitation Treatment of Loess

by Xinwen Wang, Wenle Hu, Ke Chen and Weijing Wang

Buildings 2025, 15(17), 3222; https://doi.org/10.3390/buildings15173222 - 7 Sep 2025

Viewed by 480

Abstract

This study examines the effects and mechanisms of different Enzyme-Induced Carbonate Precipitation (EICP) treatments on loess structure improvement. The study focuses on ordinary EICP and three modified methods using MgCl₂, NH₄Cl, and CaCl₂. A series of unconfined [...] Read more.

This study examines the effects and mechanisms of different Enzyme-Induced Carbonate Precipitation (EICP) treatments on loess structure improvement. The study focuses on ordinary EICP and three modified methods using MgCl₂, NH₄Cl, and CaCl₂. A series of unconfined compressive strength (UCS) tests, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and elemental mapping were used to assess both macroscopic performance and microscopic characteristics. The results indicate that ordinary EICP significantly enhances loess particle bonding by promoting calcite precipitation. MgCl₂-modified EICP achieves the highest UCS (820 kPa) due to delayed urea hydrolysis and the formation of aragonite alongside calcite, which results in stronger and more continuous cementation. In contrast, NH₄Cl reduces urease activity and reverses the reaction, which limits carbonate precipitation and weakens structural cohesion. Excessive CaCl₂ leads to a “hijacking mechanism” where hydroxide ions form Ca(OH)₂, restricting carbonate formation and diminishing the overall enhancement. This study highlights the mechanisms behind enhancement, degradation, and diversion in the EICP process. It also provides theoretical support for optimizing loess subgrade reinforcement. However, challenges such as uneven permeability, environmental variability, and long-term durability must be addressed before field-scale applications can be realized, necessitating further research. Full article

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

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22 pages, 4360 KB

Open AccessArticle

Mechanical Behavior Analysis of Pipe Roof Using Different Arrangements in Tunnel Construction

by Yanbin Luo, Benxian Gao, Jianxun Chen, Chuanwu Wang, Miao Wang and Xiong Qiao

Buildings 2025, 15(17), 3221; https://doi.org/10.3390/buildings15173221 - 7 Sep 2025

Viewed by 468

Abstract

For tunnels constructed in a single direction, the pipe roof at the tunnel exit portal can be installed either as Outside-to-Inside advanced support arrangements (Out–In ASA) or Inside-to-Outside advanced support arrangements (In–Out ASA). To investigate the pipe roof’s mechanical behavior and deformation characteristics [...] Read more.

For tunnels constructed in a single direction, the pipe roof at the tunnel exit portal can be installed either as Outside-to-Inside advanced support arrangements (Out–In ASA) or Inside-to-Outside advanced support arrangements (In–Out ASA). To investigate the pipe roof’s mechanical behavior and deformation characteristics under two excavation methods, this study establishes Pasternak two-parameter elastic foundation beam models for the pipe roof. Corresponding boundary conditions are proposed for each support configuration, and the governing differential equation for pipe roof deflection is derived and solved. The Hanjiashan Tunnel is used as an engineering case study to validate the theoretical results by comparing them with field monitoring data. A comparative analysis and parametric sensitivity study are then conducted for the two construction methods. The results show that theoretical predictions align well with the field measurements, confirming the validity of the proposed model. This study proposed calculation parameters for the Hanjiashan Tunnel. Under this circumstance, the method of Out–In ASA has been proven to offer improved structural performance and safety when the tunnel face is close to the portal. Moreover, the timely installation of the initial support and the strong bearing capacity of the surrounding rock can further reduce pipe roof deformation near the tunnel exit. Therefore, the Out–In ASA method is recommended for single-direction tunnel excavation. If the method of Out–In ASA is not feasible due to site constraints, the method of In–Out ASA can be adopted, while early support and effective grouting should be guaranteed to ensure control of excessive deformation. The findings of this study can provide a theoretical reference for the construction of tunnel portals in single-direction excavation. Full article

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

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20 pages, 1750 KB

Open AccessArticle

Comparative Energy Balance Analysis—Case Study of Total Binder Energy Demand Evaluation

by Matúš Kozel, Ľuboš Remek, Štefan Šedivý, Juraj Šrámek and Grzegorz Mazurek

Buildings 2025, 15(17), 3220; https://doi.org/10.3390/buildings15173220 - 6 Sep 2025

Viewed by 552

Abstract

Energy demand is a critical challenge for sustainable infrastructure, yet in road asset management, it is rarely considered a central decision criterion. Most decision frameworks remain focused on financial and structural performance. This study introduces a comparative Energy Balance Analysis (EBA) as a [...] Read more.

Energy demand is a critical challenge for sustainable infrastructure, yet in road asset management, it is rarely considered a central decision criterion. Most decision frameworks remain focused on financial and structural performance. This study introduces a comparative Energy Balance Analysis (EBA) as a complementary tool to existing life-cycle approaches. A case study is presented in which the only variable is binder composition—conventional 50/70 bitumen versus the same binder modified with 3% styrene–butadiene–styrene (SBS) polymer. The methodology integrates material-level energy demand estimation, laboratory performance testing, and pavement life modeling with HDM-4, and vehicle operational energy analysis. Results show that although SBS modification increases initial binder production energy by 13.3%, it doubles pavement service life and avoids mid-life rehabilitation, leading to a net saving of 110,671.75 MJ over 20 years. These findings confirm that early-stage material improvements can generate long-term energy efficiency gains. The study thus demonstrates the potential of EBA as a practical decision-support tool for sustainable pavement management. Full article

(This article belongs to the Special Issue Advances in Sustainable Pavement and Road Construction: Innovations with Asphalt and Recycled Materials)

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23 pages, 6286 KB

Open AccessArticle

Study on Punching Shear Performance of Concrete-Filled Steel Tubular Column-Slab Column Joints in Metro Stations

by Wufeng Mao, Yanmei Ruan, Yuhui Li, Rui Liang, Chenyang Xiao, Yuan Mei and Hongping Lu

Buildings 2025, 15(17), 3219; https://doi.org/10.3390/buildings15173219 - 6 Sep 2025

Viewed by 356

Abstract

To investigate the strain patterns and shear failure mechanisms of concrete-filled steel tube (CFT) column-end-plate joints during construction, this study designed and fabricated a scaled model of a standard subway station section based on similarity theory. Model tests were conducted under static earth [...] Read more.

To investigate the strain patterns and shear failure mechanisms of concrete-filled steel tube (CFT) column-end-plate joints during construction, this study designed and fabricated a scaled model of a standard subway station section based on similarity theory. Model tests were conducted under static earth pressure loads, and a finite element model was constructed for comparative analysis. The study focused on the ultimate bearing capacity, failure modes, and force transmission mechanisms of the joint, and optimized the analysis using reinforcement parameters. The results showed significant stress concentrations at the joint corners and core, with shear forces gradually forming annular cracks in the top slab concrete. The bearing system formed by the steel tube column and flange was the primary force transmission mechanism, and even after damage, the steel tube could still effectively restrain the core concrete. Increasing the steel bar diameter and increasing the number of slab reinforcements parallel to the beam significantly improved the joint’s mechanical properties. Improving the material properties of the reinforcement increased the joint’s stress and displacement capacity. This research provides a reference for optimizing the design and construction of slab-column joints in subway stations. Full article

(This article belongs to the Special Issue Advancing Civil Engineering Construction and Management: Innovations in Green Building, Intelligent Construction, and Sustainable Infrastructure Development)

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Buildings, Volume 15, Issue 17 (September-1 2025) – 271 articles

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