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Buildings, Volume 12, Issue 10 (October 2022) – 280 articles

Cover Story (view full-size image): This study investigated 48 conventional LSF and MBS floors for their structural and insulation Fire Resistance Levels using Finite Element Modelling (FEM) and Heat Transfer Analyses (HTA) techniques. Full-scale experimental fire tests were modelled using FEM methods, and the validity of the techniques was verified prior to the analyses of parametric floor systems. The structural behaviour of the channel section joists in the elevated temperatures was studied, and hence a correlation was established to determine the critical steel temperature at the structural fire failure with respect to the applied Load Ratio (LR). View this paper
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17 pages, 5117 KiB  
Article
Decision Analysis of a Reinforcement Scheme for In-Service Prestressed Concrete Box Girder Bridges Based on AHP and Evaluation of the Reinforcement Effect
Buildings 2022, 12(10), 1771; https://doi.org/10.3390/buildings12101771 - 21 Oct 2022
Cited by 2 | Viewed by 3138
Abstract
Prestressed concrete girder bridges are widely used worldwide due to their mature construction technology, economical cost, and low maintenance. After a certain number of years of service, prestressed concrete girders inevitably suffer from deterioration of their material properties, cracking, and reduced load-carrying capacity [...] Read more.
Prestressed concrete girder bridges are widely used worldwide due to their mature construction technology, economical cost, and low maintenance. After a certain number of years of service, prestressed concrete girders inevitably suffer from deterioration of their material properties, cracking, and reduced load-carrying capacity due to the natural environment and long-term vehicle loading. When the performance of a bridge declines to the point that it cannot meet the requirements of normal use, reinforcement and maintenance are required. In this study, a 5 × 45 m prestressed concrete continuous box girder bridge that has been in service for 25 years is taken as an example, and the causes of crack development and deterioration of the technical condition of the bridge are analyzed. Based on an analysis of the causes, reinforcement schemes for overall replacement of the girder and adding bridge piers are proposed. According to a comparison of the advantages and disadvantages, a decision analysis of the reinforcement scheme is carried out via the analytic hierarchy process (AHP). The vector weights of the two schemes were found to be 0.4288 and 0.5712, respectively, indicating that adding bridge piers is more advantageous than overall replacement of the girder. Thus, a scheme of adding five piers was adopted to reinforce the bridge. A load test was then performed after the reinforcement, and both the test deflection and strain calibration coefficients were found to be less than 1, indicating that the force state of the added piers and bearings was better than the theoretical calculations. The present study shows that the reinforcement scheme of adding piers can achieve the design goal. The working status of the box girder was significantly improved, the crack development of box girder was suppressed, and the service life of the bridge was prolonged. Full article
(This article belongs to the Section Construction Management, and Computers & Digitization)
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16 pages, 5257 KiB  
Article
Use of Eco-Friendly Materials in the Stabilization of Expansive Soils
Buildings 2022, 12(10), 1770; https://doi.org/10.3390/buildings12101770 - 21 Oct 2022
Cited by 6 | Viewed by 1622
Abstract
Volume change of expansive soils is a challenging issue, which affects various engineering structures all over the world. Consequently, we need environmentally-friendly and cost-effective soil stabilizers to address the challenges related to expansive soils. The utilization of natural fibers allows for the reduction [...] Read more.
Volume change of expansive soils is a challenging issue, which affects various engineering structures all over the world. Consequently, we need environmentally-friendly and cost-effective soil stabilizers to address the challenges related to expansive soils. The utilization of natural fibers allows for the reduction in environmental impact since they are renewable and biodegradable raw materials. Moreover, the current article presents an experimental approach to study the effect of natural fibers on the mechanical behavior of expansive soils. Various experimental tests—such as Atterberg limits, standard compaction, direct shear, swelling potential, and swelling pressure—were conducted on control and treated soil samples using different percentages of fibers. The results of measurements of the physico-mechanical properties after reinforcement of the soil with 1%, 5%, and 10% of natural fibers indicate that the mechanical behavior of expansive soils is greatly influenced by the addition of natural fibers. To conclude, 86% reduction was observed in the swelling coefficient of treated soil. Future research can be done to check the durability of the current practice in detail. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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18 pages, 6317 KiB  
Article
Use of Processed Sugarcane Bagasse Ash in Concrete as Partial Replacement of Cement: Mechanical and Durability Properties
Buildings 2022, 12(10), 1769; https://doi.org/10.3390/buildings12101769 - 21 Oct 2022
Cited by 15 | Viewed by 3385
Abstract
Using biomass waste as supplementary cementing material (SCM) in concrete has attracted researchers’ attention for efficient waste utilization and reducing cement demand. Sugarcane bagasse ash (SCBA) is one such example of biomass waste. It is an agricultural waste obtained when sugarcane bagasse from [...] Read more.
Using biomass waste as supplementary cementing material (SCM) in concrete has attracted researchers’ attention for efficient waste utilization and reducing cement demand. Sugarcane bagasse ash (SCBA) is one such example of biomass waste. It is an agricultural waste obtained when sugarcane bagasse from the sugar industry is used for power generation and disposed of in open-air dumping sites. Its waste disposal causes the generation of particulate matter, degrading air quality. In this study, the effect of processed SCBA as SCM in concrete has been investigated. The processing of the SCBA involved the removal of fibrous and carbon-containing particles by sieving followed by grinding. The SCBA was ground for 45 min until the surface area was comparable to that of cement and was then used for further characterization and incorporation into concrete. The 45 min grinding time resulted in 2.92 times higher pozzolanic reactivity of the SCBA. The SCBA was incorporated by replacing cement in different weight fractions (10%, 20%, 30%, 40%) in concrete. Test results showed that the concrete workability increased with SCBA incorporation, whereas the resulting concrete density was reduced. The results of the mechanical properties, including compressive sstrength and hardened density, were enhanced upon the cement replacement by SCBA. Concrete containing 30% SCBA can be used for structural applications as its 28 days compressive strength was 21 MPa, which complies with ACI 318-16 specifications. Concrete resistance against scaling and leaching due to adverse effects of sulfuric and hydrochloric acid considerably increased with SCBA addition and was due to microstructure densification by secondary hydrates formation as lower portlandite content was detected by thermogravimetric analysis. Hence, SCBA processing increases its reactivity, as reflected by the improved mechanical properties and greater durability of SCBA-incorporated concrete. Full article
(This article belongs to the Collection Sustainable Building Materials: Design and Digitization)
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25 pages, 7547 KiB  
Article
Performance of Polyethylene Vapor Barrier Systems in Temperate Climates
Buildings 2022, 12(10), 1768; https://doi.org/10.3390/buildings12101768 - 21 Oct 2022
Cited by 2 | Viewed by 1835
Abstract
The performance of nine different vapor barrier systems comprising polyethylene (PE) membranes were assessed. The vapor barrier systems comprised membranes of virgin PE, 100% new PE, regenerated PE and multilayered virgin and regenerated PE. Membranes were joined either with tape suited to the [...] Read more.
The performance of nine different vapor barrier systems comprising polyethylene (PE) membranes were assessed. The vapor barrier systems comprised membranes of virgin PE, 100% new PE, regenerated PE and multilayered virgin and regenerated PE. Membranes were joined either with tape suited to the individual system or an adhesive base on butyl rubber. The vapor barrier systems were evaluated and compared using standard laboratory tests. Chemical analytical techniques and physicomechanical tests were used. Mechanical properties were assessed using laboratory tests recommended by the harmonized standard EN 1385. Chemical analyses followed standard laboratory protocols performed with specialized equipment and visual examination. Chemical and mechanical properties were determined before and after exposure to an aging regime comprising 168 days at 70 °C in total. The chemical stability of the plastic present in each membrane was further evaluated after an additional exposure to an aging regime comprising 50 days followed by another 30 days at 70 °C. Additional aging indicated chemical changes in the membrane material with time. However, it was not possible to distinguish between aging properties for membranes containing virgin PE, 100% new PE, regenerated PE or multilayered virgin and regenerated PE. Full article
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17 pages, 7956 KiB  
Article
Numerical Evaluation of the Flow Field of an Isothermal Dual-Corner Impinging Jet for Building Ventilation
Buildings 2022, 12(10), 1767; https://doi.org/10.3390/buildings12101767 - 21 Oct 2022
Cited by 3 | Viewed by 1254
Abstract
The corner impinging jet ventilation is a new air distribution system for use in office environments. This study reports the mean flow field behavior of dual isothermal corner-placed inlets based on an impinging jet in a square-shaped room with the size of 7.2 [...] Read more.
The corner impinging jet ventilation is a new air distribution system for use in office environments. This study reports the mean flow field behavior of dual isothermal corner-placed inlets based on an impinging jet in a square-shaped room with the size of 7.2 m × 7.2 m. A detailed numerical study is carried out to evaluate the influence the different configuration parameters, such as the inlet placement, same side or opposite side, and supply airflow rate, have on the flow field. The results show that the highest velocity peak for all cases is obtained at x = 0.5 m and the lowest at x = 3.5 m. The velocity profiles development remains similar when increasing the flow rate. For the zone evaluation, the results show that Case 1 and 2 (V = 20 L/s) meet the requirement of not exceeding 0.15 m/s during the heating season in the occupied zone according the BBR standard both for same-side and opposite-side configurations. For Case 4, the optimal placement of the inlets is opposite to each other when V = 30 L/s for the BBR requirements. Case 1, 2, 3, 4, 5, and 7 all meet the requirement of not exceeding 0.25 m/s during the cooling season both for the same-side and opposite-side configurations. For Case 8, the optimal placement of the inlets is opposite to each other when V = 50 L/s. Full article
(This article belongs to the Special Issue Computational Fluid Dynamics Modeling for Smart Buildings Design)
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31 pages, 19455 KiB  
Article
Comprehensive Evaluation of Thermal Comfort in Ship Cabins: A Case Study of Ships in Yangtze River Basin, China
by and
Buildings 2022, 12(10), 1766; https://doi.org/10.3390/buildings12101766 - 21 Oct 2022
Cited by 2 | Viewed by 1300
Abstract
In recent years, the waterway navigation and transportation industry has been developing rapidly, and the living environment of ship cabins has not received much attention. Using questionnaire surveys, data collection and computer simulations, this study explored the problems and causes related to thermal [...] Read more.
In recent years, the waterway navigation and transportation industry has been developing rapidly, and the living environment of ship cabins has not received much attention. Using questionnaire surveys, data collection and computer simulations, this study explored the problems and causes related to thermal comfort that affect a crew living onboard. The survey showed differences in the thermal sensations of the crew. Cabins below the deck of a ship are usually more comfortable than those above deck. These differences were related to the range of frequent activities undertaken in the cabins. The data and calculations show that the thermal comfort in the stern winch cabin and the engine cabin was significantly higher than in the top living cabin and the meeting cabin. For cabins without windows in winter, the PMV and PPD indexes of those below deck were on average 11.95% higher and 7.03% lower, respectively, than those above deck, indicating better overall thermal comfort below deck. The simulation showed that the simulated PMV of an occupied cabin was up to 17.55% higher than the actual PMV, indicating that the number of crew members in the cabin significantly affected its level of thermal comfort. The results provide a reference for understanding and improving the thermal environment of ships and temporary water facilities. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
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12 pages, 7796 KiB  
Article
A Post-Analysis of the Introduction of the EU Directive 92/57/EEC in the Swedish Construction Industry
Buildings 2022, 12(10), 1765; https://doi.org/10.3390/buildings12101765 - 21 Oct 2022
Cited by 1 | Viewed by 1207
Abstract
The EU directive 92/57/EEC focuses on ensuring that health and safety-related matters are taken into consideration during every stage of construction-related work and has been introduced into the regulations of the member countries. In 2006, Sweden was tasked by the European Commission to [...] Read more.
The EU directive 92/57/EEC focuses on ensuring that health and safety-related matters are taken into consideration during every stage of construction-related work and has been introduced into the regulations of the member countries. In 2006, Sweden was tasked by the European Commission to clarify its implementation of the directive, including which management roles and responsibilities were to come into effect during both the planning and eventual execution of construction work—changes that ultimately were introduced into the national regulations in 2009. Focusing on the accident trends in the construction industry in the years immediately following these regulatory changes, we find that the new management roles and responsibilities had no apparent effect on the accident rates. Furthermore, we argue that there is a need to broaden the analysis regarding the implementation of the EU directive 92/57/EEC to also include nation-specific changes to health and safety management and policy. These qualitative studies should also include a dedicated focus on how changes to management structures and processes may affect the prevalence of occupational diseases specifically. Full article
(This article belongs to the Special Issue Occupational Health and Diseases in Built Environment)
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20 pages, 3897 KiB  
Article
Exploring the Renovation Status and Flexible Strategies of Urban Housing in China Based on Two Surveys of Residents and Architects
Buildings 2022, 12(10), 1764; https://doi.org/10.3390/buildings12101764 - 21 Oct 2022
Viewed by 1547
Abstract
Housing renovations have become an important part of the construction of living environments in China, and improving residential flexibility is an important way to facilitate renovations. This study focused on the adjustments of interior space and living function from the perspective of the [...] Read more.
Housing renovations have become an important part of the construction of living environments in China, and improving residential flexibility is an important way to facilitate renovations. This study focused on the adjustments of interior space and living function from the perspective of the application of flexible design strategies through two-stage surveys. The renovation contents and needs of 439 residents were statistically analyzed, an evaluation of design strategies was performed by 226 architects, and a correlation analysis was carried out based on the data. The results showed that the distribution of renovations was positively related to the renovation difficulty and could be summarized into four parts, viz., functional arrangement, device and pipeline, furniture and storage, and decorative details, while the willingness to renovate was related to living requirements. Twenty design strategies for improving housing flexibility were evaluated, and a statistical analysis was carried out on the flexibility assessment and adoption willingness provided by architects. In 14 of these strategies, the flexibility assessment affected the architects’ willingness to adopt the design (p < 0.05); however, the adoption willingness was affected by external factors in the other six strategies, such as cost control. In addition, the architects’ adoption willingness score was generally lower than their assessment score for the same strategy; thus, top-level guidance to promote the application of flexible strategies should be strengthened. Full article
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14 pages, 2919 KiB  
Article
Early-Age Properties Evaluation of Nano-Metakaolin Cement Paste Based on Electrochemical Impedance Spectroscopy
Buildings 2022, 12(10), 1763; https://doi.org/10.3390/buildings12101763 - 21 Oct 2022
Cited by 3 | Viewed by 1244
Abstract
The early-age properties of nano-metakaolin (NMK) cement paste were examined from 15 min to 24 h, contacted between cement and water based on the electrochemical impedance spectroscopy (EIS) method. The effects of a superplasticizer and chloride ions were taken into consideration. The variation [...] Read more.
The early-age properties of nano-metakaolin (NMK) cement paste were examined from 15 min to 24 h, contacted between cement and water based on the electrochemical impedance spectroscopy (EIS) method. The effects of a superplasticizer and chloride ions were taken into consideration. The variation of the electrochemical parameters of NMK cement paste with or without the superplasticizer and chloride ions was analyzed. The results demonstrated that the solution resistance and impedance modulus of the cement paste decreased first then increased between 15 min and 12 h after cement contact with water. When the cement contacted with water within about 8 h, the pore solution resistance and impedance modulus were less affected by NMK. When the cement hydration was over about 8 h, the pore solution resistance and impedance modulus of the cement paste were significantly improved by the addition of 1% NMK. The pore solution resistance of the cement paste with 1% NMK was increased by 0.49%, 2.64% and 18.17% as compared with ordinary cement paste when the hydration time was 4 h, 8 h and 12 h, respectively. NMK promoted cement hydration and increased the pore solution resistance and impedance modulus in the cement paste with or without the superplasticizer and chloride ions. The superplasticizer and chloride ions reduced the pore solution resistance and impedance modulus of cement paste with or without NMK. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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19 pages, 5270 KiB  
Article
Optimization of Preparation Method, Nucleating Agent, and Stabilizers for Synthesizing Calcium Chloride Hexahydrate (CaCl2.6H2O) Phase Change Material
Buildings 2022, 12(10), 1762; https://doi.org/10.3390/buildings12101762 - 21 Oct 2022
Cited by 5 | Viewed by 2624
Abstract
This study investigates improvements in low-cost latent heat storage material calcium chloride hexahydrate (CaCl2.6H2O). Its melting point is between 25 and 28 °C, with relatively high enthalpy (170–190 J/g); however, this phase change material (PCM) shows supercooling and phase [...] Read more.
This study investigates improvements in low-cost latent heat storage material calcium chloride hexahydrate (CaCl2.6H2O). Its melting point is between 25 and 28 °C, with relatively high enthalpy (170–190 J/g); however, this phase change material (PCM) shows supercooling and phase separation. In CaCl2.6H2O incongruent melting causes lower hydrates of CaCl2 to form, which affects the overall energy storage capacity and long-term durability. In this work, PCM performance enhancement was achieved by adding SrCl2.6H2O as a nucleating agent and NaCl/KCl as a stabilizer to prevent supercooling and phase separation, respectively. We investigated the PCM preparation method and optimized the proportions of SrCl2.6H2O and NaCl/KCl. Thermal testing for 25 cycles combined with DSC and T-history testing was performed to observe changes in enthalpy, phase transitions and supercooling over the extended period of usage. X-ray diffraction was used to verify crystalline structure in the compounds. It was found that the addition of 2 wt.% of SrCl2.6H2O reduced supercooling from 12 °C to 0 °C compared to unmodified CaCl2.6H2O. The addition of 5 wt.% NaCl or KCl proved to effectively suppress separation and the melting enthalpy achieved was 169 J/g–178 J/g with congruent melting over 25 cycles, with no supercooling and almost no reduction in the latent heat. Full article
(This article belongs to the Topic Energy Saving and Energy Efficiency Technologies)
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23 pages, 1799 KiB  
Review
Sustainable Construction through Resource Planning Systems Incorporation into Building Information Modelling
Buildings 2022, 12(10), 1761; https://doi.org/10.3390/buildings12101761 - 21 Oct 2022
Cited by 2 | Viewed by 1886
Abstract
The latest industrial revolution 4 enabled significant performance improvement through technological advancements. Simultaneously, the industry is setting high-level expectations for changing business practices toward long-term benefits in all three sustainability dimensions. The concept of sustainability embraces all production and operation processes in the [...] Read more.
The latest industrial revolution 4 enabled significant performance improvement through technological advancements. Simultaneously, the industry is setting high-level expectations for changing business practices toward long-term benefits in all three sustainability dimensions. The concept of sustainability embraces all production and operation processes in the Architecture, Engineering, and Construction (AEC) industry. This study systematically explores the literature on sustainability with Enterprise Resource Planning (ERP) and Building Information Modelling (BIM) technologies in the AEC industry and the sustainability vision for their integration. The different types of ERP and BIM implementations have similarities in addressing the broad scope of functionalities. The emergence and proliferation of ERP and BIM have brought crucial changes to the business environment. Further evolution to cloud-based operations is transforming companies from technology-oriented practices to data-centric decision-making smart infrastructures. The narrative literature review investigates the sustainability insights and ideas in ERP and BIM solutions, presenting state of the art on systems integration topics. The relevant literature was retrieved to achieve the research objectives which were qualitatively analyzed to generate the basis for further research. Full article
(This article belongs to the Special Issue Sustainability and Energy Efficiency in Smart Cities and Construction)
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15 pages, 1024 KiB  
Article
Examining the Effect of Urban Rail Transit on Property Prices from the Perspective of Sustainable Development: Evidence from Xuzhou, China
Buildings 2022, 12(10), 1760; https://doi.org/10.3390/buildings12101760 - 21 Oct 2022
Viewed by 1332
Abstract
Urban rail transit (URT) promotes sustainable urban development by alleviating traffic congestion and environmental degradation. However, many cities have developed URT projects recently, often encumbering local governments with debt. Land value capture (LVC) is an important theory that explores the new financing modes [...] Read more.
Urban rail transit (URT) promotes sustainable urban development by alleviating traffic congestion and environmental degradation. However, many cities have developed URT projects recently, often encumbering local governments with debt. Land value capture (LVC) is an important theory that explores the new financing modes for urban rail transit. Despite prior studies that have found a positive relationship between URT and property prices based on LVC, limited empirical studies explore sustainable paths to better examine the effect of URT on property prices. This study collects 1036 properties in Xuzhou, China. Meanwhile, multiple regression models are established to analyze the impact mechanism of URT on property prices, and to further examine the combination effects of multidimensional neighborhood infrastructure and URT on property prices from the perspective of sustainable development. The results show that the coefficients of URT in all models are negative, indicating that the property prices decrease as the distance from the URT to the property increases, and the positive coefficient of TRANS implies that the transfer station would raise house prices. Combining Park, School (and Hospital) variables with URT, respectively, the negative coefficients of URT increase from 0.0435 to 0.0846 and 0.0525, and these URT variables are significant, indicating that parks, schools, and hospitals can enhance the effect of URT on property prices. However, adding the Shopping variable, the negative value of URT drops from 0.0435 to 0.0192, and is not significant, which means shopping centers have a restraining impact. Moreover, the combination of parks and schools (and hospitals) can better enhance the effect of URT on property prices (the highest URT negative coefficient is 0.0870). This study can provide a reference for the government to facilitate URT planning and better decision-making. Full article
(This article belongs to the Collection Buildings, Infrastructure and SDGs 2030)
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15 pages, 519 KiB  
Article
Comparison of Machine Learning Approaches for Medium-to-Long-Term Financial Distress Predictions in the Construction Industry
Buildings 2022, 12(10), 1759; https://doi.org/10.3390/buildings12101759 - 20 Oct 2022
Cited by 4 | Viewed by 1490
Abstract
A method for predicting the financial status of construction companies after a medium-to-long-term period can help stakeholders in large construction projects make decisions to select an appropriate company for the project. This study compares the performances of various prediction models. It proposes an [...] Read more.
A method for predicting the financial status of construction companies after a medium-to-long-term period can help stakeholders in large construction projects make decisions to select an appropriate company for the project. This study compares the performances of various prediction models. It proposes an appropriate model for predicting the financial distress of construction companies considering three, five, and seven years ahead of the prediction point. To establish the prediction model, a financial ratio was selected, which was adopted in existing studies on medium-to-long-term predictions in other industries, as an additional input variable. To compare the performances of the prediction models, single-machine learning and ensemble models’ performances were compared. The comprehensive performance comparison of these models was based on the average value of the prediction performance and the results of the Friedman test. The comparison result determined that the random subspace (RS) model exhibited the best performance in predicting the financial status of construction companies after a medium-to-long-term period. The proposed model can be effectively employed to help large-scale project stakeholders avoid damage caused by the financial distress of construction companies during the project implementation process. Full article
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33 pages, 9284 KiB  
Article
Nonlinear Modeling of RC Substandard Beam–Column Joints for Building Response Analysis in Support of Seismic Risk Assessment and Loss Estimation
Buildings 2022, 12(10), 1758; https://doi.org/10.3390/buildings12101758 - 20 Oct 2022
Cited by 3 | Viewed by 2775
Abstract
The paper discusses how joint damage and deterioration affect the seismic response of existing reinforced concrete frames with sub-standard beam–column joints. The available simplified modeling techniques are critically reviewed to propose a robust, yet computationally efficient, technique for simulating the nonlinear behavior of [...] Read more.
The paper discusses how joint damage and deterioration affect the seismic response of existing reinforced concrete frames with sub-standard beam–column joints. The available simplified modeling techniques are critically reviewed to propose a robust, yet computationally efficient, technique for simulating the nonlinear behavior of substandard beam–column joints. Improvements over the existing models include the simulation of the cyclic deterioration of joint stiffness and strength, as well as pinching in the hysteretic response, implemented considering a deteriorating hysteretic rule. A fiber-section forced-based inelastic beam–column element is developed, considering improved material models and fixed-end rotation due to bond failure, rebars-slip, and inelastic extension, to simulate the deteriorating cyclic behavior of existing pre-cracked beam–column members. For the assessment of frames with substandard exterior beam–column joints, a nonlinear model for the exterior joint is developed and validated through a full-scale quasi-static cyclic test performed on a substandard T-joint connection. The proposed model allows considering structural performance in risk assessment while accounting for true inelastic mechanisms at the joints. An assessment of a five-story RC frame revealed that the activation of the joint shear mechanism increases the chord rotation demand on the connecting beam members by up to 85%, with increases of up to 62% (mean drift) and 89% (mean + 1.std.) on the lower floors when determining the inter-story drift demand, and the collapse probability of structures subjected to design base ground motions increased from 4.20% to 29.20%. Full article
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12 pages, 1174 KiB  
Article
Lean and Sustainable Project Delivery in Building Construction: Development of a Conceptual Framework
Buildings 2022, 12(10), 1757; https://doi.org/10.3390/buildings12101757 - 20 Oct 2022
Cited by 4 | Viewed by 2492
Abstract
The shortage of constructive philosophies, principles, techniques, and tools in construction project delivery and sustainability before the 1990s, together with the abundance of them after 2000, creates two different eras which are of prime importance. The former one’s considerable advantage was a common [...] Read more.
The shortage of constructive philosophies, principles, techniques, and tools in construction project delivery and sustainability before the 1990s, together with the abundance of them after 2000, creates two different eras which are of prime importance. The former one’s considerable advantage was a common understanding and set of practices (e.g., the critical path method for scheduling), which seems to be a goal to achieve in the later one. In this regard, the combination and integration of best practices, tools, and techniques in construction project delivery can be considerably helpful for benefiting from their advantages and covering their limitations. Thus, this study aims to develop a conceptual framework for lean and sustainable project delivery in building construction projects. To do so, a systematic literature review was carried out, through which 230 studies were located and analyzed via thematic analysis to realize the purpose of this study. The findings present a conceptual framework for project delivery which combines and integrates sustainability, lean construction, and building information modeling in terms of principles, practices, tools, and techniques. Practically, this study’s results inform practitioners in the construction industry on the lean and sustainable delivery of building construction projects. Full article
(This article belongs to the Section Construction Management, and Computers & Digitization)
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28 pages, 22593 KiB  
Article
Experimental Study and Finite Element Calculation of the Behavior of Special T-Shaped Composite Columns with Concrete-Filled Square Steel Tubulars under Eccentric Loads
Buildings 2022, 12(10), 1756; https://doi.org/10.3390/buildings12101756 - 20 Oct 2022
Cited by 2 | Viewed by 1433
Abstract
Special T-shaped composite columns with concrete-filled square steel tubulars have good restraint on internal concrete, are convenient to process, have a high bearing capacity and good mechanical properties, and can increase the aesthetics of the building and the utilization rate of indoor space. [...] Read more.
Special T-shaped composite columns with concrete-filled square steel tubulars have good restraint on internal concrete, are convenient to process, have a high bearing capacity and good mechanical properties, and can increase the aesthetics of the building and the utilization rate of indoor space. Theoretical analysis, experimental study, and numerical simulation of the eccentric compression performance of the special-shaped column are carried out. Taking the specimen length, eccentric distance, and eccentric direction as test parameters, nine specimens with different slenderness ratios were designed to carry out eccentric compression tests. The eccentric compression performance was numerically simulated and analyzed by the general finite element software ABAQUS. The results show that the short column mainly suffers section strength failure, while the middle and long columns mainly suffer bending instability failure without torsional deformation. The degree of influence of the test parameters decreases in turn according to the eccentric distance, eccentric direction, and length of the specimen; there is no weld cracking phenomenon, and the square steel pipes can work together. The finite element calculation results are in good agreement with the experimental and theoretical values. Full article
(This article belongs to the Special Issue Prefabricated and Modular Steel Structures)
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19 pages, 1862 KiB  
Article
Climate Change Performance of nZEB Buildings
Buildings 2022, 12(10), 1755; https://doi.org/10.3390/buildings12101755 - 20 Oct 2022
Cited by 5 | Viewed by 1491
Abstract
Buildings are one of the key factors in working towards a low-carbon economy to help mitigate climate change. For this reason, many of the current regulations aim to reduce their consumption and increase their efficiency, as is the case in the European Union [...] Read more.
Buildings are one of the key factors in working towards a low-carbon economy to help mitigate climate change. For this reason, many of the current regulations aim to reduce their consumption and increase their efficiency, as is the case in the European Union with the Energy Performance of Buildings Directive (EPBD). Terms such as nearly zero-energy buildings (nZEB) or zero-emission buildings (ZEB) are increasingly used. However, these terms and regulations focus on energy and emissions, ignoring user comfort. This research shows the performance of these buildings in the face of climate change, as their strengths are not limited to energy consumption or emissions, but also to improving user comfort. By examining the compliance of a real semi-detached house with the different Spanish energy regulations (NBE-CTE 79, CTE-DB HE 2013 and CTE-DB HE 2019), its performance in terms of energy and comfort in different future scenarios defined by the Intergovernmental Panel on Climate Change (IPCC) is evaluated. The results show that the building with nZEB criteria (CTE-DB-HE 2019) reduces its energy consumption by an average of 84.36% compared to the other two energy standards. In terms of comfort, measured according to the Fanger criteria (steady state model), the hours throughout the year in the “neutral” thermal sensation category are similar; however, the hours in the “slightly cool” category are reduced by 57%, improving by up to eight times the “slightly warm” category. The nZEB building proves to be more resilient to climate change by mitigating and homogenizing its response to climatic variations. Full article
(This article belongs to the Special Issue Building Energy-Saving Technology)
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19 pages, 7541 KiB  
Article
Automation of Construction Progress Monitoring by Integrating 3D Point Cloud Data with an IFC-Based BIM Model
Buildings 2022, 12(10), 1754; https://doi.org/10.3390/buildings12101754 - 20 Oct 2022
Cited by 9 | Viewed by 3277
Abstract
Automated construction progress monitoring using as-planned building information modeling (BIM) and as-built point cloud data integration has substantial potential and could lead to the fast-tracking of construction work and identifying discrepancies. Laser scanning is becoming mainstream for conducting construction surveys due to the [...] Read more.
Automated construction progress monitoring using as-planned building information modeling (BIM) and as-built point cloud data integration has substantial potential and could lead to the fast-tracking of construction work and identifying discrepancies. Laser scanning is becoming mainstream for conducting construction surveys due to the accuracy of the data obtained and the speed of the process; however, construction progress monitoring techniques are still limited because of the complexity of the methods, incompleteness of the scanned areas, or the obstructions by temporary objects in construction sites. The novel method proposed within this study enables the extracting of BIM data, calculating the plane equation of the faces, and performing a point-to-plane distance estimation, which successfully overcomes some limitations reported in previous studies, including automated object detection in an occluded environment. Six datasets consisting of point clouds collected by static and mobile laser scanning techniques including the corresponding BIM models were analyzed. In all the analyzed cases, the proposed method automatically detected whether the construction of an object was completed or not in the as-built point cloud compared to the provided as-planned BIM model. Full article
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24 pages, 5091 KiB  
Article
Proposal for the Integration of Health and Safety into the Design of Road Projects with BIM
Buildings 2022, 12(10), 1753; https://doi.org/10.3390/buildings12101753 - 20 Oct 2022
Cited by 1 | Viewed by 2399
Abstract
The high number of accidents in the construction sector makes the concept of prevention through design (PtD), which starts with the integration of an occupational risk assessment in this phase, increasingly important. To this end, BIM (building information modelling) is a methodology that [...] Read more.
The high number of accidents in the construction sector makes the concept of prevention through design (PtD), which starts with the integration of an occupational risk assessment in this phase, increasingly important. To this end, BIM (building information modelling) is a methodology that provides benefits related to the management of health and safety in the design phase. Its application in linear work projects is less developed than its application in building, even more so with regard to health and safety in BIM. This research proposes a methodology for integrating risk assessment into the design phase of BIM road projects, structuring the information, establishing the information integration processes, its analysis and risk management, and automating its integration into the model through zones. As a result, the research enables risk assessment in the BIM model through zones, differentiating risk values and allowing for the analysis of interferences between certain activities and the study of other specific activities in the design. As a result of the structure and organisation of the data, it is possible to export the data to IFC for coordination with other stakeholders. Thus, the final contribution of the research is the introduction of health and safety into road projects conducted with BIM, in compliance with legal requirements. Full article
(This article belongs to the Special Issue Proactive and Advanced Research on Construction Safety Management)
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22 pages, 2062 KiB  
Article
BIM Roles and Responsibilities in Developing Countries: A Dedicated Matrix for Design-Bid-Build Projects
Buildings 2022, 12(10), 1752; https://doi.org/10.3390/buildings12101752 - 20 Oct 2022
Cited by 7 | Viewed by 4170
Abstract
Building information modeling (BIM) through data-rich digital representation has revolutionized the architecture, engineering, and construction (AEC) industry. BIM implementation in the AEC industry has noticeably increased over the last decade. Various BIM roles have been discussed in the literature to ease the process [...] Read more.
Building information modeling (BIM) through data-rich digital representation has revolutionized the architecture, engineering, and construction (AEC) industry. BIM implementation in the AEC industry has noticeably increased over the last decade. Various BIM roles have been discussed in the literature to ease the process of BIM implementation, but the BIM roles related to project delivery methods have not been standardized. Stimulated by this need, this study develops a BIM roles and responsibilities matrix (BIM-R&R) in the context of the design−bid−build (DBB) projects for developing countries. A comprehensive literature review has been conducted, followed by a questionnaire survey comprising 105 responses. The results were analyzed to formulate a BIM-R&R matrix, on which the expert opinion was obtained from the BIM experts. The proposed BIM-R&R matrix describes all the roles and their corresponding responsibilities required along the project life cycle phases of DBB projects. The incorporation of BIM roles in the DBB procurement process will aid in the efficient management of all information and data that may be lost due to the fragmented nature of DBB. BIM roles with enhanced communication and coordination will also help in reducing time and cost overruns while maintaining a high-quality product. This study helps the associated construction industry in its efforts to implement BIM on their projects by providing a method by which to assess which BIM roles are necessary. Moreover, it will provide project and construction managers with a clear understanding of the BIM roles in DBB projects. Full article
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18 pages, 5261 KiB  
Article
Seismic Response of a Liquefiable Site-Underground Structure System
Buildings 2022, 12(10), 1751; https://doi.org/10.3390/buildings12101751 - 20 Oct 2022
Cited by 1 | Viewed by 1368
Abstract
To study the dynamic response of a saturated sand-underground structure system subjected to earthquakes, a series of shaking table tests with a geometric scale ratio of 1/30 were conducted. Based on the experimental acceleration records of testing soil deposits, the relationship between dynamic [...] Read more.
To study the dynamic response of a saturated sand-underground structure system subjected to earthquakes, a series of shaking table tests with a geometric scale ratio of 1/30 were conducted. Based on the experimental acceleration records of testing soil deposits, the relationship between dynamic shear stress and horizontal soil displacement was analyzed by the 1D shear beam inverse calculation method. Meanwhile, the development law of the equivalent dynamic horizontal subgrade reaction coefficient and the dynamic strain of the sidewall in the underground structure has also been discussed. The testing results indicate that the dynamic shear stress of the soil deposit under the bottom plate of the underground structure is larger than that of the soils surrounding the sidewall and above the roof plate; in addition, the soil displacement tends to decrease with the buried depth. The dynamic shear stress–displacement hysteretic loop of the soil deposits tends to be plump as the input amplitude increases. The spectral characteristics of ground motions obviously influence both the dynamic shear stress–displacement hysteretic curve and the excess pore water pressure ratio of saturated sand soil, especially under medium and strong excitations. The equivalent dynamic horizontal subgrade reaction coefficient decreases with the increase of soil depth, and the difference between the coefficient above and underneath the underground structure model can reach 7.589 MN/m3. On the contrary, the equivalent dynamic horizontal subgrade reaction coefficient decreases with the increase of the input amplitude of ground motions, and the maximum reduction ratios of the coefficient are 74.4%, 66.7%, and 47.3%, corresponding to the El-Centro, Kobe, and Wolong ground motions, respectively. The soil liquefaction has a certain effect on the equivalent dynamic horizontal subgrade reaction coefficient. In general, the dynamic strain at the top of the sidewall in the underground structure is higher than that at the bottom of the sidewall, which illustrates that the deformation of underground structures is in good agreement with the seismic deformation mode of soil deposits. Full article
(This article belongs to the Special Issue Advanced Studies of Risk Resistant Building Structures)
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16 pages, 5874 KiB  
Article
Reliability Analysis of RC Slab-Column Joints under Punching Shear Load Using a Machine Learning-Based Surrogate Model
Buildings 2022, 12(10), 1750; https://doi.org/10.3390/buildings12101750 - 20 Oct 2022
Cited by 9 | Viewed by 1824
Abstract
Reinforced concrete slab-column structures, despite their advantages such as architectural flexibility and easy construction, are susceptible to punching shear failure. In addition, punching shear failure is a typical brittle failure, which introduces difficulties in assessing the functionality and failure probability of slab-column structures. [...] Read more.
Reinforced concrete slab-column structures, despite their advantages such as architectural flexibility and easy construction, are susceptible to punching shear failure. In addition, punching shear failure is a typical brittle failure, which introduces difficulties in assessing the functionality and failure probability of slab-column structures. Therefore, the prediction of punching shear resistance and corresponding reliability analysis are critical issues in the design of reinforced RC slab-column structures. In order to enhance the computational efficiency of the reliability analysis of reinforced concrete (RC) slab-column joints, a database containing 610 experimental data is used for machine learning (ML) modelling. According to the nonlinear mapping between the selected seven input variables and the punching shear resistance of slab-column joints, four ML models, such as artificial neural network (ANN), decision tree (DT), random forest (RF), and extreme gradient boosting (XGBoost) are established. With the assistance of three performance measures, such as root mean squared error (RMSE), mean absolute error (MAE), and coefficient of determination (R2), XGBoost is selected as the best prediction model; its RMSE, MAE, and R2 are 32.43, 19.51, and 0.99, respectively. Such advantages are also reflected in the comparison with the five empirical models introduced in this paper. The prediction process of XGBoost is visualized by SHapley Additive exPlanation (SHAP); the importance sorting and feature dependency plots of the input variables explain the prediction process globally. Furthermore, this paper adopts Monte Carlo simulation with a machine learning-based surrogate model (ML-MCS) to calibrate the reliability of slab-column joints in a real engineering example. A total of 1,000,000 samples were obtained through random sampling, and the reliability index β of this practical building was calculated by Monte Carlo simulation. Results demonstrate that the target reliability index requirements under design provisions can be achieved. The sensitivity analysis of stochastic variables was then conducted, and the impact of that analysis on structural reliability was deeply examined. Full article
(This article belongs to the Special Issue Applications of (Big) Data Analysis in A/E/C)
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14 pages, 7126 KiB  
Article
Analysis of Urban Spatial Accessibility of Museums within the Scope of Seoul
Buildings 2022, 12(10), 1749; https://doi.org/10.3390/buildings12101749 - 20 Oct 2022
Cited by 4 | Viewed by 1731
Abstract
While urban accessibility of museums plays a crucial role in the growth of a cultural city, in reality, an uneven distribution of museums exists in cities. In particular, museums are concentrated in certain regions or located in a place that is different from [...] Read more.
While urban accessibility of museums plays a crucial role in the growth of a cultural city, in reality, an uneven distribution of museums exists in cities. In particular, museums are concentrated in certain regions or located in a place that is different from the cognitive experience of local residents. To solve this issue, this study quantified the urban space of Seoul, which has entered into the status of a cultural city since the 1990s, as its target city by using space syntax. Further, a suitability analysis was conducted by extracting the museums’ topological accessibility in the city structure as well as the accessibility by the travel angle and limit distance setting. The results showed that the physical locations of museums considering the minimum walking distance set in this study were somewhat separated or isolated from primary spaces where people travel. This indicates that determining museum locations by referring to the major travel routes throughout the city is a significant basis for securing physical accessibility. This study is meaningful as it establishes reference materials for determining museum locations in Seoul and will help form physical clusters of museums adjacent to each other. Full article
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14 pages, 2761 KiB  
Article
Seismic Risk Mitigation and Management for Critical Infrastructures Using an RMIR Indicator
Buildings 2022, 12(10), 1748; https://doi.org/10.3390/buildings12101748 - 20 Oct 2022
Cited by 5 | Viewed by 1197
Abstract
Recent earthquake events have highlighted the importance of critical infrastructure (CI) resilience, as a strong correlation was found between economic loss and severity of CI damage. CIs are characterized by a complex structure composed of sub-components that are essential for the continuous performance [...] Read more.
Recent earthquake events have highlighted the importance of critical infrastructure (CI) resilience, as a strong correlation was found between economic loss and severity of CI damage. CIs are characterized by a complex structure composed of sub-components that are essential for the continuous performance of the system. CI owners and governments allocate ample resources to retrofitting and upgrading CI systems and components to increase the resilience of CIs and reduce risk in case of seismic events. Governments and decision makers must manage and optimize the retrofitting efforts to meet budget and time constraints. This research presents a probabilistic methodology for CI seismic risk mitigation and management. The risk expectancy is appraised according to an FTA-based stochastic simulation. The simulation includes the development of exclusive fragility curves for the CI and an examination of the expected damage distribution as a function of earthquake intensity and fragility uncertainty of the components. Furthermore, this research proposes a novel RMIR (risk mitigation to investment ratio) indicator for the priority setting of seismic mitigation alternatives. The RMIR is a quantitative indicator that evaluates each alternative’s cost-effectiveness in terms of risk expectancy mitigation. Following the alternative’s RMIR value, it is possible to prioritize the alternatives meeting budget and time constraints. This paper presents the implementation of the proposed methodology through a case study of a generic oil pumping station. The case study includes twelve mitigation alternatives examined and evaluated according to the RMIR indicator. Full article
(This article belongs to the Special Issue Seismic Risk Analysis and Management of Structure Systems)
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32 pages, 26869 KiB  
Article
Development of a Framework to Support Whole-Life-Cycle Net-Zero-Carbon Buildings through Integration of Building Information Modelling and Digital Twins
Buildings 2022, 12(10), 1747; https://doi.org/10.3390/buildings12101747 - 20 Oct 2022
Cited by 17 | Viewed by 4072
Abstract
Decision-making on whole-life-cycle net-zero-carbon buildings is critical for addressing carbon emission and environmental problems. However, there is a lack of a data integration framework and an open international standard approach integrating key decision variables to support scientific computations and decision-making for whole-life-cycle net-zero-carbon [...] Read more.
Decision-making on whole-life-cycle net-zero-carbon buildings is critical for addressing carbon emission and environmental problems. However, there is a lack of a data integration framework and an open international standard approach integrating key decision variables to support scientific computations and decision-making for whole-life-cycle net-zero-carbon buildings. Building information modelling (BIM) is an open international standard representing building information. Digital Twin (DT) can capture and monitor real-time building conditions to facilitate building operation. Integrating information acquired by DT with BIM has considerable potential to enable an open international standard based computational representation of key decision variables throughout the whole-building life cycle process. This paper aims to develop a novel conceptual framework that integrates BIM and DT to support net-zero-carbon buildings. The framework is developed using an open international standard approach and the ontology-based representation method, to define key decision variables using entities, properties, and relationships, and integrates captured data via DT. The research makes significant contributions to enable net-zero-carbon buildings and paves the way for future research on an automated system to support decision-making for the whole-life-cycle net-zero-carbon buildings. Full article
(This article belongs to the Collection Sustainable Buildings in the Built Environment)
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17 pages, 7068 KiB  
Article
The Early Age Hydration Products and Mechanical Properties of Cement Paste Containing GBFS under Steam Curing Condition
Buildings 2022, 12(10), 1746; https://doi.org/10.3390/buildings12101746 - 20 Oct 2022
Cited by 4 | Viewed by 1459
Abstract
The hydration products and strength of cement pastes incorporated with ground blast furnace slag (GBFS) (0% and 20% replacement) have been investigated under steam curing condition (80 °C for 7 h and 7 d) in comparison with normal curing condition (moist curing for [...] Read more.
The hydration products and strength of cement pastes incorporated with ground blast furnace slag (GBFS) (0% and 20% replacement) have been investigated under steam curing condition (80 °C for 7 h and 7 d) in comparison with normal curing condition (moist curing for 28 d). The results show that, during the initial 80 °C steam curing for 7 h, in addition to the filler effect, GBFS is still involved in cement hydration. The abundant available Al phase and Mg phase in GBFS promote the formation of flake-like hydrotalcite, foil-like C-(A)-S-H gels, as well as equant grain-shaped C-(A)-S-H gels. Prolonging the steam curing time to 7 d further improves the formation of hydrogarnet. Since the formation of both hydrogarnet and hydrotalcite can consume the available Al, steam curing for 7 d seems to favor the formation of low Al C-(A)-S-H gels. In addition, due to the formation of a large amount of hydration products, the influence of 20% GBFS addition on the demolding strength of initial steam-cured cement mortar (80 °C for 7 h) is almost negligible. However, further extending the steam curing time to 7 d increases the strength gap between 20% GBFS blended cement mortar and pure cement mortar, and the related mechanism is discussed. Full article
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30 pages, 7469 KiB  
Article
Dynamic Characteristic and Decoupling Relationship of Energy Consumption on China’s Construction Industry
Buildings 2022, 12(10), 1745; https://doi.org/10.3390/buildings12101745 - 19 Oct 2022
Cited by 4 | Viewed by 1539
Abstract
(1) Background: The decoupling of energy consumption from economic growth in the construction industry is crucial to the sustainable development of the global construction industry. The existing studies focus on the advancements in energy efficiency by designers for building monoliths or construction techniques, [...] Read more.
(1) Background: The decoupling of energy consumption from economic growth in the construction industry is crucial to the sustainable development of the global construction industry. The existing studies focus on the advancements in energy efficiency by designers for building monoliths or construction techniques, involving no exploration of energy efficiency management from a regional perspective, which is unfavorable for the formulation of energy efficiency policies and systematic control of the construction industry by local governments. (2) Methods: From the perspective of regional management, this paper constructs an integrated analysis and application framework of “spatio-temporal characteristics + matching evaluation + policy design” based on the decoupling model and GIS tools. It studies the spatio-temporal characteristics of energy consumption in the construction industry in 30 provinces of China from 2010 to 2019, and its decoupling relationship with the economic development of the construction industry, and proposes an optimal zoning and recommendations for energy consumption in the construction industry, providing a reference for energy conservation management in the construction industry in China. (3) Results: First, the change of energy consumption amount (ECA) in the construction industry in the provinces was dominated by ascent, while the energy consumption intensity (ECI) predominantly decreased, and most provinces are still in a period of growth or plateau in energy consumption. Second, ECA and ECI had prominent spatial heterogeneity and aggregation. High-energy-consuming regions are concentrated along the coast and along the Yangtze River, while low-energy-consuming regions are mainly clustered in remote areas, such as the northeast, northwest, and southwest of China. Energy consumption shows a clear north-south difference in intensity, with high-intensity regions clustered in the north compared to low-intensity regions in the south. Third, most of the provinces were in strong negative decoupling, expansive coupling, and weak decoupling, and better decoupling regions were mainly gathered in south and central China. Nearly one half of these provinces showed decoupling degradation and only a few achieved evolution, with evolutionary regions clustered mainly in central and southern China. The northeast and northwest were the key problem areas of energy-saving transformation in China’s construction industry. (4) Conclusion: The 30 provinces were divided into three types: leader, intermediate, and laggard, and the development goals and suggestions on low energy consumption in the construction industry for three zones were put forward, significantly improving the precision of policy design and implementation. The study in this paper expands the research perspective on energy saving management in the construction industry and provides a methodology and basis for developing energy efficiency policies and plans for the construction industry in China and similar developing countries. Full article
(This article belongs to the Special Issue Building Energy and Sustainability)
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23 pages, 5312 KiB  
Article
A Mesoscopic Viewpoint on Slurry Penetration and Pressure Transfer Mechanisms for Slurry Shield Tunneling
Buildings 2022, 12(10), 1744; https://doi.org/10.3390/buildings12101744 - 19 Oct 2022
Cited by 2 | Viewed by 1115
Abstract
The penetration characteristics of the slurry and the support pressure transfer mechanisms are critical to the tunnel face stability control during a mechanized excavation. In this paper, numerical calculations coupling computational fluid dynamics (CFD) with the discrete element method (DEM) are carried out [...] Read more.
The penetration characteristics of the slurry and the support pressure transfer mechanisms are critical to the tunnel face stability control during a mechanized excavation. In this paper, numerical calculations coupling computational fluid dynamics (CFD) with the discrete element method (DEM) are carried out to simulate sand column penetration tests considering different particle size ratios. The reasonableness of the numerical model is verified by comparing the variation patterns of the soil permeability coefficients monitored in the numerical tests with the results of existing laboratory tests. The mesoscopic transport characteristics of the slurry particles in the sand soil pores are considered based on numerical tests, while the slurry support effects corresponding to different penetration types are evaluated. Three main basic types of slurry infiltration are observed due to the different ratios of slurry particle size over soil pore size. For the first penetration type, the slurry particles are accumulated and able to form a supporting filter cake. The slurry support is effective because of the significant pressure drop generated on both sides of the filter cake. For the second penetration type, both a filter cake and an infiltration zone are present. A dense filling network is formed between the filter cake and the penetration zone. The third type corresponds to a purely penetration zone. An effective impermeable filling network cannot be formed, and the slurry support effect is not obvious. The development of slurry penetration distance shows an obvious time effect; the farther the penetration distance, the larger the slurry filtration loss, and the worse the transformation effect of slurry support pressure. Full article
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16 pages, 664 KiB  
Article
Developing a Model Based on the Radial Basis Function to Predict the Compressive Strength of Concrete Containing Fly Ash
Buildings 2022, 12(10), 1743; https://doi.org/10.3390/buildings12101743 - 19 Oct 2022
Cited by 2 | Viewed by 1104
Abstract
A supplemental pozzolanic material such as fly ash may result in a reduction in the concrete’s adverse environmental effect by reducing the discharge of carbon dioxide throughout the cement production procedure. This pozzolanic material also enhances the mechanical characteristics as well as the [...] Read more.
A supplemental pozzolanic material such as fly ash may result in a reduction in the concrete’s adverse environmental effect by reducing the discharge of carbon dioxide throughout the cement production procedure. This pozzolanic material also enhances the mechanical characteristics as well as the durability of concrete material. Considering the boundless passion for utilizing fly ash and conducting extensive research studies, the extent to which this supplement can be added to concrete has a limitation equal to almost one-third of cement material’s weight. In the current study, a model based on the Radial Basis Function (RBF) is developed to estimate the compressive strength of concrete containing various amounts of fly ash at any arbitrary age. Having parameters used as inputs in ANN modeling such as concrete additives and characteristics of fly ash, the output was compressive strength. It was concluded that the estimated results agree well with the experimental measurements with an MSE of 0.0012 for the compressive strength. Simple and practical equations are proposed to present a simple means to determine the compressive strength of fly ash-based concrete. Full article
(This article belongs to the Special Issue Aggregate Concrete Materials in Constructions)
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21 pages, 3367 KiB  
Article
Maturity Assessment of Intelligent Construction Management
Buildings 2022, 12(10), 1742; https://doi.org/10.3390/buildings12101742 - 19 Oct 2022
Cited by 5 | Viewed by 2295
Abstract
In the new era of Construction 4.0, the application of a large number of intelligent information technologies (ITs) and advanced managerial approaches have brought about the rapid development of intelligent construction management (ICM). However, it is still unclear how to assess the maturity [...] Read more.
In the new era of Construction 4.0, the application of a large number of intelligent information technologies (ITs) and advanced managerial approaches have brought about the rapid development of intelligent construction management (ICM). However, it is still unclear how to assess the maturity of ICM. In this study, a maturity assessment system for ICM was formulated through literature reviews, questionnaires, expert discussions and a case study. A maturity scoring table containing five assessment dimensions and twenty assessment indicators was developed, and corresponding maturity levels and a radar chart of dimensions were designed. A case study of the assessments of two construction enterprises was conducted to validate that the proposed assessment system could be used by construction enterprises to quantitatively assess their ICM maturities and obtain both overall and specific assessment results. This study also proposed practical improvement methods to improve ICM maturities for construction enterprises with different maturity levels. Furthermore, the study also discussed the development direction of ICM at present and in the short-term future, which should be paid more attention to by the construction industry. Full article
(This article belongs to the Special Issue Intelligent and Computer Technologies Application in Construction)
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