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BACKGROUND: Work-related musculoskeletal disorders (WMSDs) located in the low back and neck/shoulder regions are major concerns for both workers, workplaces, and society. Masons are prone to WMSD, because their work is characterized by repetitive work and high physical workload. However, the knowledge on the physical workload during bricklaying is primarily based on subjective measurements. OBJECTIVE: This cross-sectional field study with technical measurements aimed to quantify physical workload in terms of muscular activity and degree of forward bending during bricklaying at different working heights among masons, i.e., knee, hip, shoulder, and above shoulder height. METHODS: Twelve male (36.1±16.1 years) experienced masons participated in a cross-sectional field study with technical measurements. Surface electromyography from erector spinae longissimus and upper trapezius muscles and an inertial measurement unit-sensor placed on the upper back were used to assess the physical workload (level of muscle activation and degree of forward bending) different bricklaying heights. Manual video analysis was used to determine duration of work tasks, frequency, type, and working height. The working heights were categorized as 'knee', 'hip', 'shoulder', and 'above shoulder'. The 95 percentiles of the normalized Root Mean Square (RMSn) values were extracted assess from erector spinae and trapezius recordings to assess strenuous level muscle of muscle activation. RESULTS: The RMSn of dominant erector spinae muscle increased from hip- to shoulder height (from 26.6 to 29.6, P < 0.0001), but not from hip to above shoulder height and decreased from hip to knee height (from 26.6 to 18.9, P < 0.0001). For the dominant trapezius muscle, the RMSn increased from hip- to shoulder- and above shoulder height (from 13.9 to 19.7 and 24.0, respectively, P < 0.0001) but decreased from hip- to knee height (from 13.9 to 11.5, P < 0.0001). Compared to hip height (27.9°), an increased forward bending was detected during bricklaying at knee height (34.5°, P < 0.0001) and a decreased degree of forward bending at shoulder- and above shoulder height (17.6° and 12.5°, P < 0.0001, respectively). CONCLUSION: Based on technical measurements, bricklaying at hip height showed the best compromise between muscular load and degree of forward bending. This study contributes to the development of the work environment for masons and can help guide preventive initiatives to reduce physical workload. [ABSTRACT FROM AUTHOR]

Vocational teachers in building and construction in upper secondary school deal with complex situations of an organisational, vocational, and social kind. Recent research has shown that the teacher is the single most important factor for students' learning in school. Teacher-student relationships and the teacher's repertoire of teaching practices can be more important for the student's learning than class size, the classroom environment, and the student's socio-economic background. Beyond passing the journeyman's test, we know little about the craft knowledge and working life experiences vocational teachers in the building and construction trades have acquired over many years in the construction industry, and thus, what knowledge and experiences they bring into the vocational teacher role. Learning in working life often takes place as an integrated part of work, and it is difficult to observe how learning happens. Craft knowledge is often tacit and personal. In this narrative, phenomenologically inspired study, learning is investigated as a bodily, internal process that simultaneously depends on the interaction with the material and social environment. Through narrative interviews with eleven vocational teachers in plumbing and carpentry, this study explores the teachers' backgrounds as vocational students and apprentices, and their extensive experience as craftsmen on different construction sites. The analysis shows that the building site drives craft-related actions and situations that generate a strong craft identity, professional working life experiences, and personal growth. Craftsmen at the construction site work under constant pressure in a social, physically, and mentally demanding work environment and consecutively solve problems. As professional craftsmen in the complex working environment, the teachers also acquired social and organisational expertise, which they intuitively transferred to their role as vocational teachers. [ABSTRACT FROM AUTHOR]

Abstract The ecological and economic benefits of mycelium composites offer a promising opportunity for supporting sustainable development in Africa. This study focuses on assessing the environmental impact of mycelium composites for building and construction (MCBs) by conducting a life cycle assessment (LCA) in the context of Africa. It is demonstrated that the potential environmental impact of MCBs is substantially influenced by the use and source of electrical power for autoclaves, incubators, and ovens, making the culturing and post-processing phases the major environmental hotspots. The impact of MCB production is also relative to the energy mix of specific countries, being higher in countries that rely on fossil fuel energy (e.g., South Africa) and lower in those that rely more on renewable sources (e.g., Democratic Republic of the Congo, DRC). Furthermore, the impact of MCB production is found to be sensitive to travel distance, suggesting that situating production facilities closer to agricultural, agro-industrial, and/or forestry waste sources could be more beneficial than interregional sourcing, for example. It is also demonstrated that MCBs have the potential to be a more ecologically sustainable alternative to some conventional construction materials (e.g., concrete) over an entire life cycle. Based on the insights obtained from this LCA, some recommendations have been proposed to address potential environmental repercussions pre-emptively and proactively: this is particularly important for nations, mainly in the Global South, that exhibit low resilience to climate change due to limited economic resources. Furthermore, with the rapid expansion of mycelium composite technology, there is a need to increase awareness about its potential environmental impact and, ultimately, to mitigate its potential contribution to pressing environmental concerns (e.g., global warming and climate change). Consequently, this study also adds to the existing body of literature on LCA studies, delineating key factors for consideration in future LCA studies and providing guidance for the sustainable establishment and expansion of this technology.

The ecological and economic benefits of mycelium composites offer a promising opportunity for supporting sustainable development in Africa. This study focuses on assessing the environmental impact of mycelium composites for building and construction (MCBs) by conducting a life cycle assessment (LCA) in the context of Africa. It is demonstrated that the potential environmental impact of MCBs is substantially influenced by the use and source of electrical power for autoclaves, incubators, and ovens, making the culturing and post-processing phases the major environmental hotspots. The impact of MCB production is also relative to the energy mix of specific countries, being higher in countries that rely on fossil fuel energy (e.g., South Africa) and lower in those that rely more on renewable sources (e.g., Democratic Republic of the Congo, DRC). Furthermore, the impact of MCB production is found to be sensitive to travel distance, suggesting that situating production facilities closer to agricultural, agro-industrial, and/or forestry waste sources could be more beneficial than interregional sourcing, for example. It is also demonstrated that MCBs have the potential to be a more ecologically sustainable alternative to some conventional construction materials (e.g., concrete) over an entire life cycle. Based on the insights obtained from this LCA, some recommendations have been proposed to address potential environmental repercussions pre-emptively and proactively: this is particularly important for nations, mainly in the Global South, that exhibit low resilience to climate change due to limited economic resources. Furthermore, with the rapid expansion of mycelium composite technology, there is a need to increase awareness about its potential environmental impact and, ultimately, to mitigate its potential contribution to pressing environmental concerns (e.g., global warming and climate change). Consequently, this study also adds to the existing body of literature on LCA studies, delineating key factors for consideration in future LCA studies and providing guidance for the sustainable establishment and expansion of this technology. [ABSTRACT FROM AUTHOR]

Material efficiency (ME), making products with less material or substituting with less carbon‐intensive material without a loss of functionality, can reduce greenhouse gas (GHG) emissions and complement other strategies to mitigate climate change. Seven ME strategies for cars and homes in the G7 countries were recently modeled in a study by the International Resource Panel. Modeling indicates that ME strategies focusing on construction and use of homes could lower the overall cumulative emissions in the G7 between 2016 and 2060 by 8.5 Gt CO2e (20%), while ME strategies for the production and use of cars could reduce up to 12 Gt (24%). For both homes and cars, the strategy of more intensive use—where fewer or smaller products are required to provide the same basic service—showed the greatest potential. A review of existing ME policies reveals that attention to ME in climate policy has been limited. Policy toward ME has historically focused on waste management rather than GHG reduction. Ex post evaluation of policies that do exist, especially for recycling and related waste strategies, is infrequent. Framing efficient use of materials as a measure primarily intended for climate mitigation is relatively recent and uncommon. Production‐related policy opportunities have been neglected because using ME to reduce GHGs is novel in some sectors and because increased ME faces economic and social barriers. Rebound effects where reduction of the cost of housing or transportation can increase material consumption offsetting potential gains, a problem for all efficiency‐based approaches, is understudied and not currently addressed through policy. This article is categorized under:The Carbon Economy and Climate Mitigation > Policies, Instruments, Lifestyles, BehaviorThe Carbon Economy and Climate Mitigation > Decarbonizing Energy and/or Reducing Demand [ABSTRACT FROM AUTHOR]

Lowering the embodied carbon of building materials requires a transition away from fossil derived products towards bio-based alternatives, alongside the design and development of new clean tech biomaterials that can function as carbon sinks. This paper presents an overview of historical and existing uses of seaweeds in construction to identify gaps and opportunities for the development of seaweed-based construction materials that can support atmospheric carbon removal through algal photosynthesis. This study highlights the value of interdisciplinary research collaborations that can be situated within the expanding field of biodesign where design research and methods are used to influence the development materials science. It presents as a case study the design of seaweed bricks utilising a biorefinery framework that aims to valorise residual seaweed biomass being grown for waste-water management, identifying value-adding opportunities for this seaweed by-product and new possibilities for carbon storage in the built environment. It details the development of a 1:1 scale prototype for the purposes of an exhibition at the Art Gallery of South Australia in order to demonstrate what biomasonry products from macroalgae can look like, to build social acceptance and to encourage future uptake of sustainable seaweed construction products. [ABSTRACT FROM AUTHOR]

The construction industry is among the most prominent contributors to global resource consumption, waste production, and greenhouse gas emissions. A pivotal step toward mitigating these sectoral impacts lies in the adoption of a circular production and consumption system. The use of alternative waste materials can mitigate landfill accumulation and the associated detrimental environmental effects. To highlight unconventional materials, this study began with a bibliometric assessment via a bibliography analyzis software called “Bibliometrix” (version 4.1.3). The outputs from the analyzis can assist in identifying research trends, gaps in literature and benchmark research performance. The search engine used for sourcing publications was Scopus, using the main criteria as “Waste materials used in building and construction”. The time-period analysed was from 2013 to 2023. The results included publications obtained in journal articles, book chapters and conference proceedings. The assessment reviewed 6238 documents from 1482 sources. The results revealed an array of waste materials; however, rubber, textiles, and ceramics had a significant reduction in research attention. Rubber waste presents promising opportunities in civil concrete construction methods. The preparatory steps of textile fibres in composite materials are frequently disregarded, resulting in structural issues for the end-product. Obstacles persist in ceramic technology due to the absence of transparency, primarily because industry entities closely safeguard proprietary information. While sustainability research often emphasizes emissions, practical trials commonly revolve around integrating materials into current systems. A more comprehensive approach, contemplating the complete lifecycle of materials, could provide deeper insights into fostering sustainable construction practices. Researchers can use these findings when determining trends, research gaps, and future research directions.

Currently, there is an increasing focus on procurement contract administration as among of the key variables in explaining the performance of construction projects. Despite such observations, their relationship with quality attainment of the Force Account (FA) construction projects is not well postulated to cement the observed causal relationship. Therefore, this study assesses the role of procurement contract administration in the quality attainment of FA construction projects in Local Government Authorities (LGAs) in Tanzania. The study employed a cross-sectional research design, and data was collected by using structured questionnaires from primary schools in Dodoma, Tanzania. The study used 318 respondents to analyse data by using Partial least square structural equitation modelling (PLS-SEM). The findings of the study reveal that risk management, relationship management, dispute management, and monitoring and control are positive and significant factors in explaining the quality attainment of FA construction projects. Notably, risk management is the strongest predictor of quality attainment of FA construction projects. It was concluded that the quality attainment of FA construction projects is highly influenced by procurement contract administration. These findings have practical implications, as procurement practitioners and FA committees can use them to make decisions concerning the quality attainment of the projects through the implementation of procurement contract administration practices. [ABSTRACT FROM AUTHOR]

While previous studies have shown mixed results regarding the impact of human resource (HR) recruitment on construction project outcomes, they are limited in explaining the mechanisms through which HR recruitment influences construction project performance. The current study examines the influence of HR recruitment on the cost performance of force account construction projects, while also investigating the mediating effect of quality performance. The hypothesized model was established and empirically tested using partial least squares structural equation modeling. Data were collected from 192 force account construction projects through structured questionnaires administered to local contractors in surveyed local government authorities in Tanzania. The results reveal a positive and significant influence of HR recruitment on project cost performance. Furthermore, quality performance mediates the link between HR recruitment and cost performance. The study contributes to the limited literature on HR recruitment and construction project performance by highlighting the need for construction companies to customize their recruitment practices to align with their unique situations and needs. The findings provide practical implications to construction practitioners to enhance HR practices towards improving quality performance, which, in turn, strengthens the cost performance of force account construction projects. Additionally, the study can help policymakers develop guidelines on HR recruitment practices to ensure higher quality and cost performance in force account construction projects. [ABSTRACT FROM AUTHOR]

As tall wooden structures emerge as a burgeoning and promising sector, offering considerable ecological and financial benefits across their life cycles, their prevalence is on the rise, particularly in Europe. However, the current corpus of literature fails to offer a detailed assessment of the fundamental architectural and structural planning parameters for European tall timber towers (≥9 stories). To span this gap and improve the comprehension of the developing European tendencies, this study meticulously examined information from 33 tall timber towers in Europe. The principal findings uncovered the following: (i) tall timber buildings predominantly favored residential applications as their primary function, (ii) the prevailing preference for the central core arrangement was evident, (iii) the most prevalent design preference for tall timber buildings was prismatic forms, (iv) widespread adoption of composite materials was evident, with combinations of timber and concrete being particularly prominent, and (v) the structural systems were primarily characterized by shear-frame configurations. By revealing these present-day attributes of tall wooden towers in Europe, this article is anticipated to offer valuable insights to architectural designers, assisting and directing them in the formulation and implementation of forthcoming developments in this domain. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and numerical investigation of RCC (Reinforced Concrete) piles with helical grooves under axial and lateral loads in cohesionless soil. A set of experiments is carried out to assess the performance of RCC piles with helical grooves. To replicate the experimental findings, the Finite Element Method (FEM) is employed using Abaqus software. Three-dimensional (3D) models are created to represent both the pile and the soil using Abaqus. The paper compares settlement characteristics and lateral displacement of plain RCC piles and RCC piles with helical grooves. This study also evaluates the impact of varying the pitch of helical grooves on enhancing pile performance. The results indicate that RCC piles with helical grooves outperform plain RCC piles in terms of both axial and lateral load-carrying capacity, inferred from both experimental and analytical techniques. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the individual and combined effect of kaolin clay (KC) and shea nut shell particles (SSP) on the physical, strength, and durability properties of concrete. The cement content was replaced with up to 20% KC, and the fine aggregate content was replaced with up to 40% SSP. The concrete samples were cured for 7, 14, 28, and 90 days, and tested. The total SiO2+Al2O3+Fe2O3 content of the KC studied was 88.23%; hence, it possesses pozzolanic properties. Initial and final setting times of the KC pastes steadily increased to 154 min and 325 min at the 20% KC representing 37.5% and 14.4% increase over the control. The control mix obtained a workability value of 102 mm, and decreased steadily to 68 mm at the 20% KC and 40% SSP concrete mix, representing 50% reduction. Maximum compressive and split tensile strength values of 25.97 N/mm2 and 4.14 N/mm2 were obtained at the 15% KC and 30% SSP concrete, representing 9% and 5% increase over the control concrete respectively in 90 days curing. Furthermore, concrete with 15% KC and 30% SSP recorded 61.5% and 22.1% decrease in water absorption and sulfate attack, over the control concrete respectively in 90 days curing. It is concluded that the addition of KC and SSP positively influenced the physical, strength and durability of concrete, and therefore recommend 15% KC and 30% SSP replacements of cement and fine aggregate respectively for concrete production. [ABSTRACT FROM AUTHOR]

Facility maintenance management (FMM) is essential for ensuring long-term values and to sustain project goals throughout the life cycle delivery process. However, in underdeveloped nations such as Ethiopia, facility maintenance management is an immature and underutilised process that requires a holistic intervention for practical improvement. The main aim of this study was to identify and prioritise critical factors that affect the effectiveness of FMM, with a focus on public universities in Ethiopia. Initially, a total of thirty-three (33) crucial variables were identified with a systematic literature review and desk study. To collect primary data, a survey research design approach was utilised using questionnaires and informant interviews. A total of seventy-five (75) data sets were obtained from 180 online surveys for conducting exploratory factor analysis (EFA). The outcome of the study revealed thirteen (13) critical attributes grouped into four factors that affect the effectiveness of facility maintenance management practises. The final four-factor model includes F1, internal processes and organisation; F2, community culture, learning, and growth; F3, impacts of design and construction quality; and F4, facility maintenance approach and management. This study indicated that facility maintenance management practises in public universities in Ethiopia are immature and require extensive enhancement. The identified influencing factors highlight the need for a comprehensive intervention to promote improved facility maintenance management practises and applications in Ethiopia. Further research is needed to analyse a wider range of attributes and data using confirmatory factor analysis. [ABSTRACT FROM AUTHOR]

The construction industry is among the most prominent contributors to global resource consumption, waste production, and greenhouse gas emissions. A pivotal step toward mitigating these sectoral impacts lies in the adoption of a circular production and consumption system. The use of alternative waste materials can mitigate landfill accumulation and the associated detrimental environmental effects. To highlight unconventional materials, this study began with a bibliometric assessment via a bibliography analyzis software called "Bibliometrix" (version 4.1.3). The outputs from the analyzis can assist in identifying research trends, gaps in literature and benchmark research performance. The search engine used for sourcing publications was Scopus, using the main criteria as "Waste materials used in building and construction". The time-period analysed was from 2013 to 2023. The results included publications obtained in journal articles, book chapters and conference proceedings. The assessment reviewed 6238 documents from 1482 sources. The results revealed an array of waste materials; however, rubber, textiles, and ceramics had a significant reduction in research attention. Rubber waste presents promising opportunities in civil concrete construction methods. The preparatory steps of textile fibres in composite materials are frequently disregarded, resulting in structural issues for the end-product. Obstacles persist in ceramic technology due to the absence of transparency, primarily because industry entities closely safeguard proprietary information. While sustainability research often emphasizes emissions, practical trials commonly revolve around integrating materials into current systems. A more comprehensive approach, contemplating the complete lifecycle of materials, could provide deeper insights into fostering sustainable construction practices. Researchers can use these findings when determining trends, research gaps, and future research directions. [ABSTRACT FROM AUTHOR]

Inspection of the technical condition of load-bearing structural elements of buildings and structures in the process of their construction and operation is an important issue at the present time. A fiber-optic monitoring system is proposed as a solution to the problem of early diagnosis of defects and damage to load-bearing building structures. A scheme has been developed for testing fiber-optic sensors, which make it possible to control the stress-strain state of monolithic reinforced concrete structures. For testing, a series of monolithic concrete beams of rectangular cross section has been made reinforced with fiber optics during their manufacturing. The values of mechanical stresses and deformations arising in beams under loading have been determined. Using the tested samples as an example, it has been established that the proposed fiber-optic monitoring system (FOMS) makes it possible to control stresses and deformations (and to predict the appearance and growth of cracks) in various building structures. The main element of the system is a hardware-software complex capable of estimating the parameters of a light wave at the output of the optical fiber. The distance from the installation site of the data processing unit to the measurement point can cover the area of 30 km. At this, fiber-optic sensors operate without additional power supply from a laser with the power of up to 30 mW. The proposed monitoring system has a low cost of one measurement point, it is easy to install, which is a good alternative to the electronic beacon-recorder device and the development of optical digital technologies in construction.

The construction industry is a key player in total energy consumption. The design and construction of buildings shall be executed to minimize their negative environmental impacts. Many research studies have focused on reducing operational energy in the past decades. As a result, the proportion of embodied energy in the life cycle energy use of buildings has increased. This research adopts a holistic review method to provide a comprehensive and systematic analysis of the literature related to embodied energy in the construction industry. A bibliometric analysis is applied to obtain 269 papers from the Web of Science database during 1996–2020. A scientometric analysis is adopted for 175 publications to identify the publication year and geographical distribution, journals, scholars, citations, and keywords of publications. Results showed that the publications originated from 47 countries, and they were published in 73 journals. The United States, China, and England dominate the research publications. This indicates a strong research collaboration between developing and developed countries. The embodied energy is the top keyword in the frequency of occurrence and relationships with other keywords. The primary research areas for this topic are sustainable construction materials, information technology, sensitivity analysis of environmental impact, building type and composition, life cycle energy use of buildings, estimation methods, and life cycle analysis. An in-depth qualitative discussion is conducted to discuss research topics, identify research gaps, and propose future research directions.

The United Nations (UN) 2030 Agenda, borne from the most inclusive policy dialogue ever, emphasized partnerships built upon collaboration to achieve sustainable goals, as documented in SDG17. However, the building and construction sector has been experiencing sustainability issues, leading to several traditional government-led initiatives in the built environment. The private sector is critical to achieving the sustainable development goals (SDGs) and the 2030 Agenda by interacting with societies, governments, and other actors for a circular built environment. The circular economy (CE) is a paradigm that is becoming increasingly popular to drive the movement to sustainability, requiring the partnership of the private sector to be implemented successfully. However, the application of CE initiatives in the private sector engagement has received less attention. Recognizing the interaction of multiple parties' influence on the uptake of a CE, this study thus seeks to examine the participation of the private sector in the CE in the built environment using a mixed review approach (scientometric and content analysis). The findings reveal that the private sector faces barriers in terms of financial and economic, institutional and technological, and political and regulatory factors. This research also identified areas for greater private sector involvement in CE initiatives in the built environment, such as resource reduction, sharing, and the adaptive reuse of existing buildings. [ABSTRACT FROM AUTHOR]

The Australian Bureau of Statistics (ABS) regularly releases statistical information, for the whole of Australia, for public access. Building- and construction-related statistics are important to reflect the status of this pillar industry of Australia and help researchers, practitioners, and investors with decision-making. Due to complex retrieval hierarchy of ABS's website and irregular update frequency, it is usually time-consuming to find relevant information. Moreover, browsing the raw data from ABS's webpages could not provide the insights to the future. In this work, we applied techniques from computer science to help users in the building and construction domain to better explore the ABS statistics and forecast the future trends. Specifically, we built an integrated Web application that could help collect, sort, and visualize the ABS statistics in a user-friendly and customized way. Our Web application is publicly accessible. We further injected our insights into the Web application, based on the existing data by providing online forecasting on user's interested information. To achieve this, we identified a series of related economic factors as features and adjusted a multi-variant, LSTM-based time series forecasting model by considering the most informative factors. We also compared our approach with the most widely used SARIMA-based forecasting model to show the effectiveness of the deep learning-based models. The forecast values are depicted at the end of the time series plots, selected by the users. [ABSTRACT FROM AUTHOR]

Modifications to improve the physical, thermal, and mechanical properties of gypsum ceiling composites can be made by adding bio-fillers. Adding 1 and 3 wt% of Typha angustifolia fiber in 1D, 2D, or 3D fiber orientations, and adding 20 or 50 wt% natural rubber-latex compound were embedded into gypsum ceiling composites using a casting process. The gypsum ceiling composites added 1 wt% Typha angustifolia fiber 3D orientation (Formula 6, G-3D-1 F) resulted in optimum conditions with high compressive stress, high nail tensile resistance, high thermal shock resistance, low thermal conductivity, and a light weight with values of 315.17 ± 27.40 N, 92.10 ± 3.78 N. The received samples (G-3D-1 F) were no cracking and fracturing after autoclave testing, and 0.0796 ± 0.0005 W/m.K, respectively, better than those of the reference sample (Formula1, G-ref). Furthermore, the received samples were compared to commercial insulation materials such as concrete block, earthenware brick, light concrete brick, and cement brick with thermal conductivity values of approximately 0.546, 0.473, 0.180, and 0.126 W/m.K, respectively. The tested gypsum ceiling composites can be applied for thermal insulation and as decorative materials for construction and building to reduce energy consumption. In addition, the developed gypsum ceiling composites are easy fabrication and operation, non-toxic, inexpensive, and light weight.

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The purpose of this paper is determination the critical geometric dimensions of a three-dimensional vertical heated cavern. In this rate the convection's contribution to heat transfer will be limited due to thermal conductivity at a fixture temperature drop. The model validated and verified by comparison with the experimental results. А stable non-stationary flow regime is observed for Rayleigh number Ra = 15,000, because the temperature fields in different cross-sections of the flow coincide. For the flow with Rayleigh number Ra = 15,000, the nonstationary formulation without the turbulence model did not give the required convergence on residuals. So it was calculated by using the three-dimensional RANS approach closed with the k-w SST turbulence model. In this case the flow is unstable in the third direction, therefore it is impossible to consider the cavern as a heat insulator at numbers Ra = 10,000 and above.