Previous studies have shown that indoor environmental quality (IEQ) parameters may have a considerable effect on office employees’ comfort, health and performance. Therefore, we initiated a research program to help occupants identify IEQ parameters they perceive as risk factors for their health in an office and enhance their comfort levels in an office environment. Since we assumed that office employees might have different indoor environmental quality expectations related to their work area and that these differences could be measured, our objective was to develop an office ‘comfort map’ based on occupants’ individual IEQ preferences. Thus, the goal of the comfort map would be to help tailor office spaces to their occupants’ health and comfort expectations. The comfort survey was developed to assess the comfort-related opinions of the occupants, based on IEQ parameters (visual comfort, acoustic comfort, air quality and thermal comfort) of a chosen open-plan office building. The survey also assessed the degree to which the given IEQ parameter was considered a health risk factor by occupants or caused a negative comfort sensation for them. The survey was filled in by 216 occupants. The answers were then analyzed with the help of a frequency table depicting relative frequency. The measurements of IEQ parameters took place in an open-plan office in the chosen office building (a Hungarian subsidiary’s office building belonging to an international company in Budapest). The occupants had different opinions regarding the perceived effects of the IEQ parameters on their health and comfort. Almost two-thirds of the respondents (64.8%) were dissatisfied with the adjustability of the noises and sounds IEQ parameter at their workstation. Furthermore, half of the respondents (50.1%) were dissatisfied with the adjustability of ventilation. Most of the occupants (45.8%) considered noises and sounds as the IEQ parameter that had a negative effect on their health. There were also IEQ differences between different areas of the office space. Based on these results, a comfort map was developed for the office. The comfort map contains information about the IEQ characteristics of each workstation by depicting the thermal comfort, carbon dioxide, visual comfort and acoustic comfort characteristics of a given workstation on a relative scale. Based on the thermal, air, acoustic, and lighting differences between the workstations, occupants can select their preferred workstations when a desk-sharing system works. Although still in its pilot phase, the comfort map could increase the chances for office employees to find the workstation best suited to their IEQ expectations. This could improve occupants’ overall comfort level, which could in turn enhance occupants’ productivity and mental as well as physical health. Full article

The analysis of thermal comfort in buildings, energy consumption, and occupant satisfaction is crucial to influencing the architectural design methodologies of the future. However, research in these fields in developing countries is sectorised. Most times, the standards to study and assess thermal comfort such as ASHRAE Standard 55, EN 15251, and ISO 7730 are insufficient and not appropriate for the geographical areas of application. This article presents a scoping review of published work in Colombia, as a representative case study, to highlight the state-of-the-art, research trends, gaps, and potential areas for further development. It examines the amount, origin, extent, and content of research and peer-reviewed documentation over the last decades. The findings allow new insights regarding the preferred models and the evaluation tools that have been used to date and that are recommended to use in the future. It also includes additional information regarding the most and least studied regions, cities, and climates in the country. This work could be of interest for the academic community and policymakers in the areas related to indoor and urban climate management and energy efficiency. Full article

Satisfaction is a very important factor in improving productivity and performance in the work environment. This study aims to investigate the levels of occupants’ satisfaction with the indoor environmental quality (IEQ) in the governmental buildings in the Kingdom of Bahrain and to investigate the impact of occupants’ demographics and building attributes (non-IEQ factors) on these levels. For these purposes, the study used a questionnaire that has 17 indoor environmental quality (IEQ) factors in addition to a group of non-IEQ factors. The questionnaire was distributed by hand or using email to 279 employees in the Bahraini governmental sector. The findings of the study revealed that occupants in the Bahraini governmental buildings are not strongly satisfied with IEQ factors, especially with sound privacy, followed by visual privacy and amount of space, and then noise levels. The findings also showed that for most IEQ factors, men are more satisfied than women are, those who work in enclosed private offices are more satisfied than those who work in open-plan offices, and those who have central air-conditioning at their workplace are more than those who have a wall-mounted air conditioner. The impact of age, nature of work, duration of working in the current building and at the current workstation, weekly working hours, and proximity to the window were also investigated. Accordingly, a group of recommendations was suggested aiming to improve the levels of occupants’ satisfaction. Full article

This paper aims to propose a comprehensive framework for a clear description of system boundary conditions in life cycle energy assessment (LCEA) analysis in order to promote the incorporation of embodied energy impacts into building energy-efficiency regulations (BEERs). The proposed framework was developed based on an extensive review of 66 studies representing 243 case studies in over 15 countries. The framework consists of six distinctive dimensions, i.e., temporal, physical, methodological, hypothetical, spatial, and functional. These dimensions encapsulate 15 components collectively. The proposed framework possesses two key characteristics; first, its application facilitates defining the conditions of a system boundary within a transparent context. This consequently leads to increasing reliability of obtained LCEA results for decision-making purposes since any particular conditions (e.g., truncation or assumption) considered in establishing the boundaries of a system under study can be revealed. Second, the use of a framework can also provide a meaningful basis for cross comparing cases within a global context. This characteristic can further result in identifying best practices for the design of buildings with low life cycle energy use performance. Furthermore, this paper applies the proposed framework to analyse the LCEA performance of a case study in Adelaide, Australia. Thereafter, the framework is utilised to cross compare the achieved LCEA results with a case study retrieved from literature in order to demonstrate the framework’s capacity for cross comparison. The results indicate the capability of the framework for maintaining transparency in establishing a system boundary in an LCEA analysis, as well as a standardised basis for cross comparing cases. This study also offers recommendations for policy makers in the building sector to incorporate embodied energy into BEERs. Full article

The behavior of beam-to-column connections significantly influences the stability, strength, and stiffness of steel structures. This is particularly important in extreme non-elastic responses, i.e., earthquakes, and sudden column removal, as the fluctuation in strength and stiffness affects both supply and demand. Accordingly, it is essential to accurately estimate the strength and stiffness of connections in the analysis of and design procedures for steel structures. Beginning with the state-of-the-art, the capacity of three available component-based mechanical models to estimate the complex mechanical properties of top- and seat-angle connections with double-web angles (TSACWs), with variable parameters, were investigated. Subsequently, a novel hybrid krill herd algorithm-artificial neural network (KHA-ANN) model was proposed to acquire an informational model from the available experimental dataset. Using several statistical metrics, including the corresponding coefficient of variation (CoV), correlation coefficient (R), and the correlation coefficient provided by the Taylor diagram, this study revealed that the krill herd-ANN model achieved the most reliable predictive accuracy for the strength and stiffness of top- and seat-angle connections with double web angles. Full article

The Kingdom of Saudi Arabia (KSA), as one of the largest polluters worldwide, has released its Vision 2030 that seeks sustainable development via economic diversification to transition towards lower CO₂ energy systems. Due to fast population and economic growth, the Kingdom is undergoing an increasing volume of construction, which is projected to exacerbate the energy-related emissions. Strategies are needed to decarbonise the housing stock and help bridge the existing performance gap with the updated Saudi Building Code (SBC). This study proposes a holistic retrofitting approach for the Saudi building industry to facilitate the identification of energy consumption reduction optimisation solutions, covering the assessment of insulation, reflective coating surfaces, sun shading devices, efficient glazing solutions, building-integrated renewables, and green roofs. The proposed flexible approach proved how blended retrofit packages provide improved performance, with rooftop photovoltaic microgeneration and improved glazing technologies singlehandedly outperforming the remaining proposals for KSA’s Riyadh climate conditions. Only the photovoltaic system could meet the simulated SBC performance benchmark independently, positioning it as an instrumental tool in improving the overall effectiveness of the retrofit packages. Full article

Transitioning from demolition to deconstruction practices for end-of-life performances is gaining increasing attention following the need for the construction industry to minimise construction and demolition waste. Building information modelling (BIM) presents an opportunity for sustainable deconstruction. However, the notion of BIM for deconstruction (BIMfD) is still in its infancy in the United Kingdom. Although a few studies on BIMfD are evident, a focus on identifying the underlying factors necessary for successful implementation of BIMfD is lacking. The purpose of this study was to identify and analyse the underlying factors necessary for BIMfD implementation in the UK construction industry. It employed a four-stage research design. The reviewed literature explored extant views on BIM implementation factors to identify an initial list of possible factors influencing BIMfD implementation. Subsequently, a mix of questionnaire, focus group discussions and structured interviews were employed at various stages to refine and contextualise 15 factors necessary for BIMfD implementation in the UK construction industry. The contextual interrelationships among the factors were evaluated using interpretive structured modelling (ISM). This evaluation culminated in a BIMfD implementation factor model. The findings identified BIMfD experts, responsiveness of business models to innovative practices and industry’s acceptance to embrace change as the principal factors influencing BIMfD implementation in the UK. The implications of the findings attest that BIMfD experts and advisors must champion the adoption and implementation of BIMfD in the UK and business models need to become more responsive to accommodate BIMfD innovative practices. A BIMfD framework was conceptualised. Even though the BIMfD framework was designed from the UK perspective, the global construction industry can leverage the outcomes of this study. This paper, therefore, brings to the fore, a hierarchical BIMfD implementation factor model to support improved deconstruction practices in the construction industry. Full article

Temporary pavilions play an important role as experimental fields for architects, designers, and engineers, in addition to providing exhibition spaces. Novel structural and formal solutions applied in pavilions also can give them an unusual appearance that attracts the eyesight of spectators. In this article, the authors explore the possibility of combining structural novelty, visual attractiveness, and low cost in the design and construction of a temporary pavilion. For that purpose, an innovative structural system and design approach was applied, i.e., a membrane structure was designed in Rhino and Grasshopper environments with the use of the Kiwi!3D IsoGeometric analysis tool. The designed pavilion, named Obverse/Reverse, was built in Opole, Poland, for the occasion of World Architecture Day in July 2019. The design and the construction were performed by the authors in cooperation with students belonging to the Humanization of Urban Environment organization from the Faculty of Architecture Wroclaw University of Science and Technology. The resultant pavilion proved the potential of obtaining a low-budget but visually attractive architectural solution with the adaption of parametrical design tools and some scientific background with innovative structural systems. Full article

For glass façade cleaning, we developed a reconfigurable robot, Mantis-mini, with a dry cleaning mechanism and linear actuator based transitioning mechanism. It consists of three suction modules, connected by a support structure and each suction module has individual differential drive wheels with independent steering capability. This paper focuses on the detailed design of the platform, static structural analysis for and kinematic formulation. The adhesion performance of the suction module is evaluated using experiments, Computational Fluid Dynamics (CFD) simulations, and analytically formulated estimation. The suction pressure magnitude predicted from the simulations increases with suction impeller speed and agrees well with measurements and analytical calculation in terms of order of magnitude and qualitative trend. An adaptive proportional-integral (PI) controller is designed and implemented for regulating suction pressure and motion controller of the platform. The suction performance of the platform is validated through real-time experiments of the platform on the glass surface. Full article

During the last few decades, there has been a greater understanding of the role of lean construction (LC) in achieving better management of construction projects and enabling the application of the fourth industrial revolution in the construction industry (Construction 4.0), which in turn, has the potential to improve the practices and outcomes in the construction industry. This paper aims to identify the barriers to adopt LC practices by taking a case of the Kingdom of Jordan. A questionnaire that included 30 barriers that were resulted from a comprehensive literature review was distributed and filled by 326 respondents from the Jordanian construction industry. The findings showed that the absence of support from the top management, low awareness toward LC, lack of training, and the absence of transparency are amongst the most serious factors that hinder the adoption of LC. The findings in this paper might be helpful to improve the knowledge about LC and support the adoption of new techniques that might improve the performance in the construction industry. Full article

Smart construction enterprises are the key subjects in the development and practical transformation of smart building technology, and their sustainable development has been a hot research topic in the new era. In the context of the new round of technology and industrial revolution, the rapid accumulation of development uncertainties and their possible transformation into risks at any time, as well as the ambiguity of growth mechanisms and the loss of strategies, have become major challenges that may constrain the development and strategic management of enterprises. Based on SWOT, BCG, GE, QSPM and principal component analysis methods, this paper constructs a new framework combining theory and practice organically for quantitative identification and evaluation of influencing factors, and analysis of strategy selection and the decision-making process. It will provide a scientific basis for sustainable development and strategic management of smart construction enterprises. DK Company is a typical smart building enterprise in China, and the results of its empirical study show that: Firstly, the 28 variable elements influencing the sustainable development of smart construction enterprises can be summarized into six key factors, with significant differences in their influence, and the external influence far greater than the internal driving force. Secondly, a priority set of six alternatives for strategic decision-making and implementation is proposed, based on the quantitative strategy selection and matching analysis, which improves the accuracy and practicality of the study findings. Full article

This study compares corrosion activities of carbon steel B450C and SS 430 (Mn in low content) exposed for 30 days in cement extract solution. Iron oxide and hydroxide were formed as corrosion products, in addition to CaCO₃, in the presence of Cr₂O₃ on SS 430. Because of the decrease in pH, B450C lost the passive state when OCP shifted to negative values, while SS 430 showed positive OCP values, maintaining its passive state. The SEM images confirmed that the corrosion attack on the surface was less aggressive for SS 430. The Nyquist plots of EIS initially showed capacitive behavior and later changed to semi-linear diffusion impedance, which SS 430 maintained firmly. The phase angle Bode diagrams confirmed these changes. Two equivalent circuits were applied. The calculated values of R_p for SS 430 increased over time (protective passive layer mainly of Cr₂O₃ oxide), while for carbon steel, R_p reached maximum value after 168 h and then decreased, maintaining minimum values approximately five orders lower than those of the stainless steel. Full article

Buildings exhibit a high energy consumption compared with other economic sectors. While percentages vary from country to country, buildings are responsible for approximately 40% of the global energy demand. Most of this is consumed for achieving human thermal comfort. In Colombia, the government promotes policies for the adoption of efficient energy strategies in this sector. The earth to air heat exchanger (EAHE) can be used to reduce the cooling load of a building. Therefore, this study aims to evaluate the energy savings that can be obtained by installing an EAHE in a tropical climate in Colombia. To do so, a mathematical model is implemented in TRNSYS (Transient System Simulation Tool) to predict the thermal performance and the cooling capacity of the EAHE. The system is modeled as a function of pipe length, diameter, material, thickness and air mass flow. Moreover, soil, local atmospheric conditions and building features are taken into account. It is found that the air leaves the EAHE at temperatures between 20.9 °C and 24.1 °C, which are approximately 3 °C below ambient temperature. Furthermore, the economic feasibility of the project is verified. Thereby, it is demonstrated that the EAHE can be a competitive alternative to current HVAC systems. Full article