Buildings, Volume 13, Issue 8 (August 2023) – 241 articles

How to balance the artistry and comfort of the light environment in an architecturalized immersive new media public art installation (AINMPAI) to ensure the safety of the audiences’ visual safety has become a new issue. The lack of corresponding lighting design standards makes this issue more challenging. This paper explores the appropriate luminance range of the irregularly curved LED screens of the AINMPAI with high-luminance natural light as the background. The influence of the audience behavior mode on the brightness threshold of the LED screens in the AINMPAI under the background of Internet communication is discussed. Through software simulation and field measurement, the effectiveness of the design measures based on the local characteristics of the work is verified. The overall average luminance, the regional luminance, the partial luminance, and the corresponding luminance contrast of the inner screen surface were measured at every 10° change in the solar altitude angle during daytime. The nighttime light environment parameters and the temperature of the device throughout the day were also measured. A total of 487 visitors were interviewed for subjective evaluation of the comfort of the light and thermal environments. The results show that: (1) the overall average luminance cannot wholly describe the actual luminance of the critical parts of the special-shaped curved screen in the device and that two indicators, the regional luminance and the partial average luminance, need to be added; (2) the maximum brightness limit of LED screens in the daytime can be 1000 cd/m² but at night it should be controlled within 200 cd/m²; (3) natural light is the main factor that causes the high average brightness and low contrast of the daytime device screen; (4) the recommended indicators for such artistic installations should balance the absolute values of average brightness, artistic effect, and transmission priority. This study can provide foundational data and a methodological reference for establishing AINMPAI light environment design guidelines or recommended standards based on audiences’ visual safety. Full article

To ensure the safety of construction site personnel and to improve the efficiency of emergency safety evacuation of site personnel, this study analyzes the risk reasons for fire accidents and the characteristics of combustion fires on construction sites. Based on a refined BIM model, a numerical simulation of the fire situation is performed using PyroSim (2019 version) software on a construction site. In the Pyrosim fire simulation model, fire scenarios with distinct construction stages and fire source locations are set up to simulate, compare, and analyze the varying pattern of each fire product in various fire scenarios. Using this information with the Pathfinder (2019 version) simulation model, a coupled simulation test of fire evacuation is conducted to assess the safety of evacuating individuals in each fire scenario. The results show that flammable materials in open spaces are more risky to burn than in confined spaces. After optimizing the utilization of safety exits and the density of people in the second simulation, it was found that the required safety evacuation time was reduced to 267 s, which is lower than the available safety evacuation time of 318.5 s for each scenario. All fire scenarios meet the safe evacuation criteria. The study results can provide a theoretical basis for developing fire response strategies for construction units and contribute to site safety management. Full article

Although there have been many studies related to construction site safety that have tried to reduce accidents, no significant improvement has been reported. Because of the complex nature of construction work processes, it is important to have a scenario-based worksite safety management system instead of reports such as safety guidelines and manuals. This study utilizes accumulated construction site accident big data, namely Construction Safety Management Integrated Information (CSI), to establish accident scenarios for different work types. To propose accident occurrence scenarios, the hazard profile managed by CSI and prior research analyses are employed for each work type and cause materials at the construction site. For accident occurrence association rules, we developed a framework based on Work Breakdown Structure–Risk Breakdown Structure (WBS-RBS) for reinforced concrete work, temporary work, and earthwork, considering 25,986 accident cases. Subsequently, association analysis was conducted to derive association rules for each work type. The accident occurrence scenarios were extracted by classifying work types (project type, activity type) and cause materials (object, location). The analysis generated 145 association rules, and 76 association rules for reinforced concrete work, temporary work, and earthwork work were extracted to derive accident scenarios, considering scenarios with high accident frequency. Furthermore, by establishing association rules between work processes, we derived accident types and occurrence rules frequently observed at construction sites. These rules formed the basis for constructing accident occurrence scenarios for each construction type based on WBS-RBS. These findings facilitate the development of appropriate safety management plans and effective accident countermeasures tailored to specific construction types and causes. The developed scenarios will help to improve construction site safety by providing useful information for safety managers and worker training. Full article

This study evaluates the vibration data of high-rise buildings during a typhoon by measuring the vibration data and using international serviceability standards. In order to do this, the horizontal vibration serviceability evaluation standards of each country were surveyed, but the standards that could be applied were limited to ISO10137 and ISO 6897. Despite the trend that the discomfort of residents increases as the number of high-rise buildings increases, the current standards are for high-frequency vibrations, such as machine vibrations or vertical floor vibrations, so there is an urgent need for research on new evaluation methods for low-frequency horizontal vibrations. As a result of analyzing the effects of typhoons on buildings, the study’s target building had low natural frequencies of less than 1 Hz, and the highest acceleration was observed to be amplified up to about 160 times due to the effects of Typhoon Danas and Chaba, but there was no change in the natural frequency. When this result was applied to the horizontal vibration serviceability evaluation, it was found that the likelihood of residents perceiving vibration was low during constant vibration, but during strong winds, the size of the top-floor horizontal vibration exceeded the average level of vibration perception proposed by ISO standards, so most residents of high-rise buildings would be likely to perceive the vibration as uncomfortable. Full article

This study evaluated the effect of alum sludge as an alternative to fly ash in fabricating geopolymer paste and mortar. The blending of this industrial waste (alum sludge and fly ash) is not only for the benefit of sustainable construction and disposal of industrial waste but also for the reduction of CO₂ emissions due to the increasing production of Portland cement from the cement production industry. A laboratory investigation was carried out on the workability and mechanical properties of geopolymer paste and mortar produced with alum sludge replacement in different proportions (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100). A combination of an alkaline solution of sodium silicate and sodium hydroxide of 14 molarity was employed as an activator for the manufacturing of both paste and mortar geopolymer specimens. It was observed from the findings that geopolymer paste and mortar was flowable and workable when alum sludge is replaced for fly ash at higher replacement content. The addition of alum sludge to the mix improved some properties such as density, strength, water absorption, and the elevated temperature behavior. It was observed that the addition of alum sludge was optimum at the 50% replacement level. The addition of alum sludge up to 50% significantly increased the compressive strength of mortar (up to 80% increase in 28 days strength). The compressive strength of the paste and mortar increased with an increase in curing age. Thus, alum sludge and fly ash can be employed together in the production of eco-friendly cementing material for environmental sustainability. Full article

Based on a practical engineering case of seismic strengthening, this paper used the enlarging cross-section method and an external self-centering substructure to improve the seismic performance and seismic resilience of existing frame structures. Among them, the external self-centering substructure included setting a self-centering precast beam and diagonal braces. Utilizing the OpenSees finite element platform, a seismic fragility analysis was carried out to compare the improvements in seismic performance and seismic resilience before and after strengthening. The analysis results show that the proposed modelling method could be simulated satisfactorily. The maximum inter-story drift and the residual inter-story drift of the strengthened frame structures decreased significantly under the same peak ground acceleration. The peak ground acceleration of the strengthened frame structures significantly increased under different performance levels. Additionally, the exceedance probability of the strengthened frame structures was obviously reduced, which reflected that the seismic performance and seismic resilience of the strengthened frame structures were significantly improved. Full article

Although shape memory alloy/Polyvinyl alcohol (SMA/PVA) hybrid fiber reinforced cementitious composites, (SMA/PVA-ECC) exhibit excellent crack closure and deformation recovery capabilities, however, the research on their fundamental mechanical properties is still limited. This study investigates the tensile mechanical properties of SMA/PVA-ECC materials by conducting uniaxial tensile tests, analyzing the failure behavior, stress–strain curves, and characteristic parameters of the specimens, comparing the influence of SMA fiber content and diameter, and establishing a tensile constitutive model. The results show that the residual crack width of SMA/PVA-ECC specimens significantly decreases after unloading, and SMA fiber content and diameter have a significant impact on the tensile properties of the specimens. The comprehensive tensile properties of specimens with a fiber diameter of 0.2 mm and content of 0.2% are the best, with their initial cracking strength, ultimate strength, and strain increasing by 56.4%, 23.6%, and 13.4%, respectively, compared to ECC specimens. The proposed bilinear tensile constitutive model has high accuracy. This study provides a theoretical basis for further research on SMA/PVA-ECC materials. Full article

Because researchers are aiming to restore the deformation and minimize the crack width of existing concrete structures, the strengthening technology of prestressed carbon-fiber-reinforced plastic (CFRP) is currently the focus of many studies and applications. In terms of the strengthening of a prestressed CFRP sheet on the flexural performance of cracked reinforced concrete beams under repeated loads, a four-point bending test of 12 beams was conducted considering the prestress degree reflected by the amount and the prestress force of the CFRP sheet. The longitudinal strengthened CFRP sheet was bonded on the bottom surface of the test beam and fixed by U-jacket CFRP sheets at the ends after tensioning. The strains of concrete, longitudinal tensile steel bars and CFRP sheets were measured at the pure bending segment of test beams, while the cracks, midspan deflection and failure pattern were recorded. The results show that the normal strain on the mid-span section of the strengthened beams by the prestress CFRP sheets was fitted for the assumption of plane section, the cracks and mid-span deflection decreased with the prestress degree of the CFRP sheets to provide better serviceability for the strengthened beams, the load capacity could be increased by 41.0–88.8% at the yield of longitudinal tensile steel bars and increased by 41.9–74.8% at the ultimate state and the ductility at the failure state was sharply reduced by 54.9–186%. The peeling off of broken CFRP sheets played a role in controlling the failure pattern of the strengthened beams under repeated loads. Finally, methods for predicting the bending performance of reinforced concrete beams strengthened by prestressed CFRP sheets were proposed. This study enriches the knowledge about damaged reinforced concrete beams that were strengthened with prestressed CFRP sheets. Full article

Tower foundations are generally of a cast-in-place structure with the disadvantages of low industrialization level and long construction period. The development of prefabricated foundation for transmission line projects is efficient to improve the industrialization level of the construction of tower foundation. In this study, the schemes of post-pouring belt U-shaped steel connection, post-pouring belt lap connection, grouting sleeve connection, and post-tensioned bond prestressed reinforcement connection, which have been widely used on building structures, are newly proposed to apply on plate foundation. The schemes were compared on processing, transporting, on-site constructing and performance. The pseudo-static tests on cast-in-place plate strip, post-pouring belt U-shaped steel connection and post-pouring belt lap connection plate strip were carried out. The results revealed that all the test plate bands were damaged in the bending mode, same as that of ordinary concrete. When U-shaped steel is adopted, more than 90% of the cast-in-place bearing capacity can be reached. The initial stiffness of prefabricated plate strip and cast-in-place strip is basically the same. The load-bearing capacity of the component is relevant to the anchorage length of the U-shaped steel. Although increasing the concrete strength of post-cast belt can improve the ultimate bearing capacity and shorten the construction period, the deformation capacity is reduced. Compared to other connection methods, post-pouring belt U-shaped steel connections have the advantage of simple construction, higher bearing capacity and stability. In summary, the post-pouring belt U-shaped steel connection scheme is recommended. Full article

The purpose of this study was to analyze the indoor air quality, in particular, the CO₂ level, in a real environment, within 16 apartments located in the municipality of Zalău, Romania, in five recently renovated multifamily buildings in which families live under normal conditions. Long-term monitoring was undertaken for 4.5 months, during the heating season of 2022–2023. A representative microclimate perspective was analyzed: the median value of the time fraction, which exceeded the Indoor Environment Quality Category I (IEQcat I) threshold for adults’ bedrooms was 82.30%. For children’s bedrooms, it was 75.65%, while for living rooms, it was 58.78%. When considering IEQcat IV, it was identified that for the bedrooms, the time fraction for which the threshold values were exceeded was still significant (median value of 45.37% for adults’ bedrooms and 50.14% for children’s bedrooms). Even if the indoor thermal comfort conditions increased, it was found that for almost half of the time, the bedrooms did not provide a health-safe indoor environment for the occupants due to inadequate ventilation, exceeding the health threshold values. Thus, it was identified that the ventilation of buildings is a key issue within the renovation process and, currently, is not properly undertaken for the mass renovation of existing multifamily residential buildings. Full article

Exposure to light during overtime work at night in confined spaces may disrupt the normal circadian clock, affect hormone secretion, sleep quality and performance, thereby posing great risks to the physical and mental health of night workers. Integrative lighting should be adopted to reduce the disturbance of normal physiological rhythm, while meeting the visual requirements of work. Through adjustable LED (CCT 6000 K/2700 K) and different vertical illuminance, five lighting patterns with different circadian stimuli (CS = 0.60, 0.30. 0.20, 0.10 and 0.05) were conducted, respectively, in a sleep lab using a within-subject design. Each lighting pattern lasted for 5 h every night. Eight healthy adults were recruited to complete the night work and their salivary melatonin, Karolinska sleepiness scale (KSS), Psychomotor Vigilance Task (PVT) and sleep quality were tested. The results showed that subjective sleepiness and melatonin concentration increased rapidly under low intervention (CS = 0.05) with the best sleep quality, while they decreased in high intervention (CS = 0.60) at night and led to significantly higher levels of sleepiness the next morning (p < 0.05). For the PVT, the middle intervention (CS = 0.30) showed the lowest response time and least errors (p < 0.05), suggesting that appropriate illuminance can improve visual performance. To reduce biorhythm disruptions, lower lighting stimulation is preferred during night work. For difficult visual tasks, high illuminances may not improve visual performance; just a slight increase in the existing lighting levels is adequate. Lighting interventions have a clear impact on sleep improvement and work capacity for those working overtime, and they may be translatable to other shift work scenarios. Full article

The high strength and stiffness-to-weight ratios of structural steel often result in relatively slender members and systems, which are governed to a great extent by stability limit states. However, predicting the stability of slender structures is difficult due to various inherent uncertainties in material and geometry. Generally, structural and member stabilities are nonlinear problems that cannot be directly evaluated based on the section strength using conventional analysis method. Nonlinear behaviors are basically categorized as materially and geometrically nonlinear, which can be observed at the cross-sectional, member, and frame levels. To provide a comprehensive understanding of the current state-of-the-art non-linear behavior and design of steel structures and to identify key areas for future research and development, this paper presents a review on the materially and geometrically nonlinear effects of steel structures. A discussion of the effects of material yielding accentuated by the presence of residual stresses, initial imperfections, and end conditions will be conducted. The stiffness reduction due to second-order effects and material yielding will be illustrated. Moreover, current and emerging design approaches that consider nonlinear responses will also be reviewed and evaluated. Lastly, with the development of modern flexible and complex steel structures, which sometimes violate fundamental assumptions of the current stability design method, the application of advanced analysis and design methods will be explored. Full article

Tunnel structures account for la large proportion of the structures in mountain highway transportation systems. Most tunnels are located in remote areas in which the geological conditions are complex and harsh and in which the layout of the management facilities along the way is complex. Thus, the management and maintenance costs of various facilities are expensive, the cost of fire safety operations and management is high, and disaster prevention and rescue have a difficult time meeting the objective requirements. Therefore, it is urgent to carry out research on quasi-unmanned operations and intelligent remote monitoring. This study firstly proposes a fire safety intelligent monitoring framework for quasi-unattended tunnels. By making full use of various intelligent sensor monitoring data in the tunnel, the tunnel operation status can be grasped in real time. Then, a fire safety evaluation model can be established through the analytic hierarchy process (AHP), and, based on the monitoring data, the AHP model parameters can be evaluated to realize the real-time evaluation and management of tunnel fire safety. Finally, on the basis of the fire safety intelligent monitoring system and the fire safety evaluation system, an adaptive fire rescue plan formulation scheme is proposed for the quasi-unattended tunnels so as to provide guaranteed support for the rapid automatic response of tunnel fire protection and to provide technical data support for the design and realization of intelligent and efficient tunnel management Full article

DC power may be more efficient than AC power in certain applications, especially when it comes to local generation and storage. This is because AC power requires extra equipment to convert it to DC power, which can lead to energy losses. Using DC power, on the other hand, makes it easier for devices to use it directly, resulting in higher energy efficiency. Additionally, using DC power can reduce equipment capital costs as it eliminates the need for additional AC–DC conversion equipment. Finally, DC power systems can offer new communication capabilities, including plug-and-play for generation and storage devices, making it simpler to integrate these systems into existing infrastructure. This paper analyzes the optimal size of a photovoltaic/PEM fuel cell system to supply a certain DC commercial load in NEOM city. To identify the best size of the PV/PEMFC, minimizing the cost of energy (COE) and minimizing the net present cost (NPC) are considered. The paper studies three sizes of PEMFCs: 15 kW, 20 kW, and 25 kW. In addition, five different PV modules are selected: Axitec 450 Watt, Jinko 415 Watt, REC Solar 410 Watt, Seraphim 310 Watt, and Tongwei 415 Watt. The results of the study confirmed that the best size of the hybrid system comprises a 15 kW PEMFC, a 267 kW Tongwei PV array, a 60 kg electrolyzer, and a 20 kg hydrogen tank. Under these conditions, the COE and NPC are 0.293 USD/kWh and 498,984 USD, respectively. Full article

In this study, a refined three-dimensional stratigraphic–structural model is established based on ABAQUS finite element software, and the basis for determining pneumatic and vibration loads is explained in detail. From this, the force characteristics of the segment and bolts with and without a cavity behind the lining under the action of multi-field coupling were analyzed, and the force law and corresponding safety of the segment structure and high-strength bolts were determined. The results show that the peak value of the maximum principal stress on the segment structure caused by the surrounding rock pressure was 92.7 times greater than the variation in the peak value of the maximum principal stress caused by additional loads (pneumatic and vibration loads). Despite this, the safety factor of the segment structure satisfied the code requirements. Compared to the situation with no cavity behind the lining, when the cavity behind the lining was small the stresses of the segment structure were large and concentrated, which increased the possibility of crack development in the segment structure. The nodal stresses and strains on the straight and bending bolts exhibited an approximately “W”-shaped distribution with a cavity behind the lining. In addition to the effect of the preload near the nut, the stress and strain at the central measurement point of the bolt rod at the joint face were larger owing to the coupling effect of multiple fields. The high-strength bolt remained in an elastic state and did not yield with damage. Full article

Low air temperature and frosting have been reported as the critical factors that greatly attenuate the efficiency and performance of the ASHP in cold regions. In order to ensure the potential prevalence of the ASHP in cold regions of China, a new ultra-low temperature ASHP unit was developed, and the field measurement was carried out in an office building where these ASHP units were installed in Shanxi Province. Results showed that a coefficient of performance (COP) of 1.83 was obtained at the ultra-low environmental temperature of −25 °C. Meanwhile, measured results indicated significant frosting suppression and improved heating performance under three typical frosting conditions. In addition, long-term measurement results revealed that the mean COP and COP_sys reached up to 3.34 and 2.63, respectively, indicating a higher performance in the cold regions of China. Consequently, the corresponding CO₂ emission reached 11.3 kg per year and per square meter, and the annual total cost on the unit reduced by 15.8% compared with the conventional ASHP, which meant that the total investment could be covered in the second year. The reduced CO₂ emission and the annual cost implied that the ASHP unit could produce better environmental and economic benefits. Findings of this study revealed that this ultra-low temperature ASHP unit had a better performance under cold environment, which offered a possibility for the prevailing of the ASHP in cold or extremely cold regions, as well as could contribute to the carbon peaking and neutralization. Full article

Shear failure is an unfavorable phenomenon as it is a brittle type of failure; however, adding rebars and fibers to a concrete beam can minimize its detrimental effects. The objective of this study was to experimentally investigate the shear behavior of high-strength concrete (HC) beams reinforced with hooked-end (H) steel fibers and high-strength steel (HS) rebars under three-point bending tests. For this purpose, nine HC beams (300 × 250 × 1150 mm in dimension) were cast with 0%, 1%, and 2% H fibers by volume in three longitudinal rebar ratios (i.e., 1.5%, 2.0%, and 3.1%) and compared with beams without fibers. Furthermore, numerical analyses were performed to validate the experimental results and compare them with design codes. The results showed that, irrespective of the fiber content or longitudinal rebar ratio, the beams failed in shear. Increasing the rebar ratio and fiber content increased the shear capacity to as high as 100% (for the specimen with 3% rebar and 2% fiber compared to its counterpart with 1% rebar and 2% fiber). In addition, the research-based equations proposed in the literature either overestimated or underestimated the shear capacity of fibrous HC beams significantly. The level of overestimation or underestimation was closely related to the sensitivity of the proposed model to the shear span ratio and the fiber content. Rebars proved to be more beneficial in contributing to the shear capacity, but the rate of this positive contribution decreased as the fiber ratio increased. Finally, the inverse analysis approach adopted herein proved to be an efficient tool in estimating the shear response of fiber-reinforced beams failing in shear (margin of error: less than 10%). Full article

Global carbon dioxide emissions can be attributed to Portland cement production; thus, an alternative cementitious system is essential to reduce cement demand. Ceramic waste powder (CWP), which contains high proportions of silica and alumina, has emerged as a promising alternative because of its chemical composition. This review discusses the potential of CWP as an alternative cementitious system and its effects on the physical, mechanical, and durability properties of cementitious systems. The findings revealed that the utilization of CWP in cementitious systems has positive effects on their physical, mechanical, and durability properties owing to the chemical composition of CWP, which can act as a filler material or contribute to the pozzolanic reaction. A pozzolanic reaction occurs between the silica and alumina in the CWP and calcium hydroxide in the cement, resulting in the production of additional cementitious materials such as calcium silicate hydrates and calcium aluminate hydrates. These additional materials can improve the strength and durability of cementitious systems. Various studies have demonstrated that CWP can be effectively used as a partial replacement for cement in cementitious systems. This can reduce the carbon footprint of construction activities by reducing the demand for Portland cement. However, the optimal amount and particle size of CWP have not been fully determined, and further research is required to optimize its use in cementitious systems. In addition, the technical and economic challenges associated with the use of CWP in construction must be further investigated to ensure its effective implementation. Full article

Experimental observations on three reinforced concrete shear walls with small shear span-to-depth ratio (SDR) under combined high vertical axial load and horizontal cyclic loads are presented. The influence of high axial load ratio (ALR) on the failure mode, hysteretic behaviour, displacement ductility, shear strength and stiffness of the squat shear walls is investigated. In addition, a novel built-in strain gauges measuring system is employed for measuring the strain conditions in the reinforcements during the whole test process. Test results indicate that high axial load restrains the development of cracks and improves the shear load capacity, but that it also decreases ductility and energy dissipation and aggravates stiffness degradation. Concrete crush and out-of-plane buckling were observed in all specimens, resulting in the final failure of the specimens. According to the strain analysis, the section of the squat walls coincided well with the assumption of plane section under the condition of high ALR. With the increase of ALR, the depth of the compression zone of members increases, while the length of plastic hinge decreases. When the axial load is relatively small, the vertical and horizontal reinforcements provided almost equal contribution to the shear capacity of squat shear walls. However, under extremely high axial load, both vertical and horizontal reinforcements cannot provide full contribution to the shear capacity. The hysteretic behaviours of the tested shear walls were simulated by a cyclic softened membrane model (CSMM). Simulation results indicate that CSMM captured well the nonlinear characteristics of the squat shear wall under high axial load. Full article

In the Architecture, Engineering, and Construction (AEC) industry, virtual environments are being utilized to enhance communication among stakeholders and improve visual comprehension. However, stakeholders possess diverse personal characteristics which can affect their spatial recognition ability in virtual spaces. Despite the potential impact of these individual traits, related research still needs to be more comprehensive. Therefore, this study analyzed how each individual’s characteristics influence spatial recognition in a Building Information Model (BIM)-based virtual environment. A quantitative methodology via a survey was employed to investigate the influence of personal factors such as age, gender, education level, and gaming experience on spatial recognition. In a 3D virtual corridor using BIM software, 76 participants were asked to navigate the corridor using a controller and count 23 sprinklers. Of the 76 participants, 30 responses were selected for the statistical analysis. The results demonstrate that age, gender, and education level did not significantly affect spatial recognition in the virtual environment. Conversely, participants with gaming experience tended to perceive spaces in the virtual environment more accurately and realistically, showing a statistically significant difference. This outcome suggests that gaming experience is crucial in enhancing spatial recognition ability in virtual environments. The findings from this study offer critical insights into the impact of individual characteristics on spatial recognition, providing valuable information for the future practical use of BIM-based virtual environments, and can subsequently assist in discovering efficient communication methods among stakeholders. Full article

The energy-supply crisis, aggravated by the war in Ukraine, has prompted EU governments to approve urgent energy-saving measures. The new Spanish energy-saving standard aims to reduce energy consumption by changing the regulatory limits for indoor hygrothermal conditions in buildings. This regulation has provoked a great social debate about its real effectiveness and its impact on user comfort. This work explores the hygrothermal performance of an office building in southeastern Spain. The objective of this research is to determine qualitatively and quantitatively how the new energy-saving standard in Spain influences energy efficiency and indoor thermal comfort, by considering the characteristics of the dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh). The scientific novelty of the study is to demonstrate that the new Spanish standard not only reduces energy costs but also makes the indoor comfort of buildings much worse; for this reason, an improvement in the standard is also proposed. The study methodology consists of a comparative study between the thermal performance, thermal comfort, and energy demand of the building, considering both the new and previous standards’ requirements. It also includes the evaluation of a proposal to improve the current standard. The results showed that the new energy-saving standard reduced energy consumption by 21.78% in comparison to former standards, but the new comfort ranges were not acceptable for 60% of the users. The proposed improvement does achieve acceptable comfort for most users (75%) and an additional reduction in energy demand of 48.76% compared to current standard. We conclude that the thermal comfort requirements of the current energy standard should be modified to better adapt the design criteria to the dry Mediterranean climate. Full article

Building information modelling (BIM) methodology has been implemented in the construction industry, reaching all sectors: multidisciplinary design development; construction planning and monitoring; and building management and maintenance. A complete BIM project aggregates several disciplines and different professionals skillsets. In order to achieve a suitable control, contributing to improve the quality of the project, a BIM manager is required. The BIM manager has the responsibility to coordinate all tasks involved in a building design, as well as the associated activities usually that are normally worked-out, complementing the project. During the development of a project, a BIM manager can access various discipline models, located in a delayering shared platform, and request responsibilities and amendments if inconsistencies are detected. The relevance of the BIM manager function is illustrated with three building cases where distinct specific projects, disciplines, and tasks were elaborated: collaboration between disciplines (architecture, structures, and construction); structural analyses and reinforcement details; quantity take-off of materials and cost estimation; construction scheduling and simulation. Although there are limitations in the software interoperability capacity, within the elaboration of a multiple stage project, BIM implementation in the construction industry has been carried out. The present study shows that the BIM manager role in projects aggregates several disciplines and experts, bringing an important improvement in the quality of the final product. A suitable BIM implementation in the construction industry needs to be supported by the most current advanced technology and in adequate BIM manager coordination. Full article

Urban green spaces have been increasingly evidenced to not only improve human health (both body and mind) and well-being but also promote a sustainable way of living for citizens as well as cities. These positive health and sustainable advantages have even greater impacts when applied to people with disabilities, which can ultimately evaluate their quality of life in the long run. Unfortunately, people with disabilities receive less attention and tend to be disregarded in terms of equal access to public facilities, health-related services, and opportunities in society. Therefore, this article emphasizes the value of having green spaces within cities and acknowledges how people with disabilities gain the benefits through active and passive methods as well as direct and indirect means at the global, population, and individual levels. With that, this article argues that urban green spaces or the development of sustainable urbanism must prioritize and include people with disabilities in the planning process, as this inclusive population has the greatest potential for advancing public resources (e.g., environmentally, socially, and economically) and moving cities closer to being truly sustainable. Full article

Dynamic loadings arising from impact, explosive, and seismic disasters impose high requirements on the performance of engineering structures during service periods. Engineered cementitious composite (ECC) exhibits exceptional toughness and crack resistance, while fiber-reinforced polymer (FRP) possesses lightweight and high-strength properties. ECC and FRP composites show promising potential in enhancing the resilience of existing structures under dynamic disaster scenarios. However, most research on ECC and FRP has primarily focused on static properties, while investigations of dynamic properties are limited. This paper provides a comprehensive review of the dynamic properties of ECC and FRP composites followed by a summary of studies conducted on the dynamic behavior of ECC and FRP strengthened members, which provides valuable insights for further research on these materials and their applications in strengthening structures under dynamic disasters. Full article

Energy prediction models and platforms are being developed to achieve carbon-neutral ESG, transition buildings to renewable energy, and supply sustainable energy to EV charging infrastructure. Despite numerous studies on machine learning (ML)-based prediction models for photovoltaic (PV) energy, integrating models with carbon emission analysis and an electric vehicle (EV) charging platform remains challenging. To overcome this, we propose a building-specific long short-term memory (LSTM) prediction model for PV energy supply. This model simulates the integration of EV charging platforms and offer solutions for carbon reduction. Integrating a PV energy prediction model within buildings and EV charging platforms using ICT is crucial to achieve renewable energy transition and carbon neutrality. The ML model uses data from various perspectives to derive operational strategies for energy supply to the grid. Additionally, simulations explore the integration of PV-EV charging infrastructure, EV charging control based on energy, and mechanisms for sharing energy, promoting eco-friendly charging. By comparing carbon emissions from fossil-fuel-based sources with PV energy sources, we analyze the reduction in carbon emission effects, providing a comprehensive understanding of carbon reduction and energy transition through energy prediction. In the future, we aim to secure economic viability in the building energy infrastructure market and establish a carbon-neutral city by providing a stable energy supply to buildings and EV charging infrastructure. Through ongoing research on specialized models tailored to the unique characteristics of energy domains within buildings, we aim to contribute to the resolution of inter-regional energy supply challenges and the achievement of carbon reduction. Full article

Stress state evaluation in axially loaded structural members is significant for sustaining and preserving the service life of buildings. While successful monitoring furnishes staunch information on the health, integrity, safety and serviceability of structures, maintaining the structural performance of a building with time significantly depends on assessing the occurrence. Variations in the stress in axially loaded members may occur in masonry buildings or space structures caused by different conditions and human-induced factors. In the last decades, numerous nondestructive methods have been generated to furnish practical means for identifying axial load in the tie-rods of masonry buildings and in the structural members of space structures. Significant effort has been put into dynamic-based approaches, which make use of the vibrational response of the monitored member to investigate its condition and evaluate the axial load. In particular, wide laboratory and field tests have been executed worldwide, resulting in several findings. Meanwhile, with flourishing sensing technology and computing power, Artificial Intelligence (AI) applications, such as hybrid methods, optimization techniques and deep learning algorithms, have become more practicable and widely used in vibration-based axial stress prediction, with efficiency and, frequently, with strict precision. While there have been various manuscripts published on dynamic-based axial stress evaluation, there are no works in which the passage from traditional methods to combinations with AI approaches have been illustrated. This article aims to address this gap by introducing the highlights of the traditional methods, and furnish a review of the applications of AI techniques used for nondestructive-based axial stress prediction in tie-rods and structural members. Conclusions, including further studies and field developments, have also been mentioned at the end of the article. Full article

A net-zero energy community (NZEC) is a promising paradigm that can directly contribute to a sustainable building sector and infrastructure. This research presents a unique empirical techno-economic optimization and evaluation approach for NZEC potential and enablers through its application to the understudied context of Kuwait. The proposed approach is unique, as it integrates data-driven and physics-based modelling capabilities, captures the impact of urban form on NZEC techno-economic performance, and quantifies through sensitivity analyses the impact of potential enablers in overcoming financial barriers to adoption. Results indicate that NZECs are far from being competitive in Kuwait compared to the business-as-usual scenario of electricity grid purchase at highly subsidized tariffs. Increasing electricity rates to a minimum of 0.03 $/kWh is recommended, coupled with investing in energy efficiency and enabling grid sell-back capabilities. Finally, results indicate that the energy demand profiles of office and multi-family buildings are more advantageous for efficient NZEC design and performance than villas, the most predominant building type in Kuwait. Limiting the share of NZEC energy demand from villas to 25% helps avoid excessive energy generation and storage capacities and costs. Full article

Optimal design of the crossbeam is essential for the economical design of bridge towers as the crossbeam could considerably enhance the lateral stiffnesses of these towers by providing a special bracing for the tower columns. By using a reliability-based approach, this paper studies the optimal design of the crossbeam stiffness factor in bridge towers; this is defined as a dimensionless crossbeam stiffness relative to the tower column stiffness. A novel second-order matrix stiffness method (MSM) is applied to obtain a closed-form solution of the lateral stiffness of the bridge tower. The structural second-order stiffness matrix consists of combinations of the second-order element stiffness matrices and coordinate transformations. Subsequently, a reliability analysis to study the optimal design of the bridge tower is performed by considering the uncertainties arising from the design and construction of the bridge tower. The lateral stiffness of the bridge tower is set as an objective function while the total usage of materials is set as a constraint condition. Then, the influence of the crossbeam stiffness factor on the lateral stiffness of the bridge tower, including the fragility curve and the probabilistic behavior, is examined. Based on the reliability analysis, optimal design recommendations on the crossbeam stiffness of the bridge tower are presented. Full article

As in many other building types, space efficiency in mid-rise timber apartment buildings is one of the critical design parameters to make a project feasible. Space efficiency depends on varying selection criteria related to construction materials, construction methods, and proper planning. To date, no study provides a comprehensive understanding of space efficiency in mid-rise timber apartment buildings. This paper examined data from 55 Finnish mid-rise timber apartment buildings built between 2018 and 2022 under the Finnish Land Use and Building Act to increase the understanding of which factors and design parameters influence the space efficiency of mid-rise timber apartment buildings. The main findings of this study indicated that: (1) among the case studies, the space efficiency ranged from 77.8% to 87.9%, and the average was 83%; (2) the mean values of the ratios of structural wall area to gross floor area, vertical circulation area to gross floor area, and technical spaces (including shafts) to gross floor area were found to be 12.9%, 2.6%, and 1.5%, respectively; (3) construction methods or shear wall materials make no significant difference in terms of space efficiency, and there is no scientific correlation between the number of stories and space efficiency; (4) the best average space efficiency was achieved with central core type, followed by peripheral core arrangement. This research will contribute to design guidelines for clients, developers, architects, and other construction professionals of mid-rise timber apartment building projects. Full article

Noncompliance with safety rules is a major cause of unsatisfactory performance in construction safety worldwide. Although some research efforts have focused on using computer vision (CV) methods for safety rule inspection, these methods are still in their early stages and cannot be effectively applied on construction job sites. Therefore, it is necessary to present a feasible prototype and conduct a detailed analysis of safety rules to ensure compliance at the job site. This study aims to extend the validation of safety rule analysis through four case scenarios. The proposed structured classification of safety rules includes categorizing them based on project phases and work stages. The construction phase-related rules are divided into four groups: (1) before work, (2) with intervals, (3) during work, and (4) after work. To validate the proposed framework, this research developed prototypes for each group’s scenarios using deep learning algorithms, a storage database to record compliance with safety rules, and an Android application for edge computing, which is required in the “before work” and “after work” groups. The findings of this study could contribute to the development of a compact CV-based safety monitoring system to enhance the current safety management process in the construction industry. Full article