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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]

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]

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 building and construction sector is a major contributor to carbon emissions in China. Hence, it is crucial to explore the characteristics and trends of building carbon emissions to achieve the carbon peak and neutrality. While previous studies have made efforts to analyze the influencing factors through different approaches, developing an effective and intelligent regression model based on machine learning algorithms remains challenging in predicting the carbon emission trend. This study analyzed carbon emissions and per capita indicators of the building and construction sector in 30 provincial regions in China from 2005 to 2021. While embodied and operational carbon emissions contribute equally to the total emissions, the results showed a significant spatial-temporal correlation. Considering the emissions as target features, nine alternative machine learning regression models were developed using eight identified explanatory features incorporating scale, economic, technological, and classification factors. Based on performance metrics encompassing root mean squared error, coefficient of determination, and mean absolute percentage error, the stacking ensemble regression model was identified to have superior performance. This model was further employed to conduct a sensitivity analysis of explanatory features on carbon emissions. The results indicated that urbanization rate and population were the most sensitive factors, with varying effects on different target features. These findings can be used to predict carbon emission trends and promote carbon reduction policies in the building industry. • Characteristics and trends analyzed for building carbon emissions during 2005–2021. • Embodied and operational carbon emissions contribute equally to the building sector. • Nine regression models developed for embodied and operational carbon emissions. • Stacking ensemble model shows superior performance with R2 values exceeding 0.910 • Sensitive features exert different influences on varying carbon emission targets. [ABSTRACT FROM AUTHOR]

This study has its bases on the concept of store equity developed by Hartman and Spiro (2005) and in the empirical model of Teixeira, Oliveira and Pires (2006), which identifies four dimensions: loyalty, memory, quality and image. The objective was to apply and test the dimensions of the model in four distinct retail brands of the building and construction segment of São Paulo, compare their store equity and segment the consumers. In each store (160 total), forty interviews were conducted. By exploratory factor analysis, it was possible to observe five dimensions related to the store equity construct: loyalty, store image, customer satisfaction, and customer care and service conformity. Through cluster analysis, respondents were classified into three different groups of consumers according to the five dimensions identified and received the categories of Unprepared, Demanding and Accustomed. Theoretical and managerial implications reinforce the possibility of applying the store equity as a customer segmentation variable in the construction retail segment. [ABSTRACT FROM AUTHOR]

Abstract Scalability is a problem common to most existing 3D printing processes, where the size of the design is strictly constrained by the chamber volume of the 3D printer. This issue is more pronounced in the building and construction industry, where it is impractical to have printers that are larger than actual buildings. One workaround consists in printing smaller pieces, which can then be assembled on-site. This workaround generates however additional design and process complexities, as well as creates potential weaknesses at the assembly interfaces. In this paper, we propose a 3D printing system that employs multiple mobile robots printing concurrently a large, single-piece, structure. We present our system in detail, and report simulation and experimental results. To our knowledge, this is the first physical demonstration of large-scale, concurrent, 3D printing of a concrete structure by multiple mobile robots. Highlights • Use multiple mobile robot printers in multi-agent settings for collaborative printing • System incorporates localisation, collision avoidance and optimal robot placement • Improve scalability and time efficiency, and demonstrate on-site printing capability • Large structure printed with proposed system in a safe, efficient and scalable manner • First multi-robot simultaneous printing on single concrete structure [ABSTRACT FROM AUTHOR]

Abstract: An emerging theme for a nation transiting into a sustainable future is the provision of a low carbon (dioxide) environment. Carbon emission reduction is therefore important for the industry and community as a whole. Buildings contribute immensely to total greenhouse gas emissions, so pragmatic actions need to be taken to cut the amount of carbon emitted by the construction industry. These typically involve strategies such as energy-saving features in the design, construction and operation of building projects. However, a variety of characteristics of the markets and stakeholders involved are suppressing their development. This paper reports on a series of interviews with a variety of Hong Kong construction project participants aimed at identifying the drivers of, and obstacles to, the construction industry's attempts to reduce carbon emissions. The results confirm the main actions currently undertaken are energy efficiency enhancement, green procurement, research and development activities, waste/water management and other technical measures such as the provision of thermal insulation. The majority of the drivers are economical in nature, suggesting that financial aids, and particularly government incentives, are likely to be useful motivators. Also suggested is the increased promotion of the benefits of environmental sustainability to the wider community, in order to alert the general public to the need for reducing the amount of carbon originating from building usage. [Copyright &y& Elsevier]

Impact modified rigid PVC formulations for the building and construction industry have evolved since their introduction in the 1960s. Formulations mainly consist of stabilised PVC with low levels of inorganic filler, pigment, and impact modifier. For outdoor applications n-butyl-acrylic grafted poly-methyl-methacrylate core/shell modifiers (AIM, a thermoset) and chlorinated polyethylene (CPE, a thermoplastic) modifiers are commonly used. It is known that CPE, especially the newer high molecular weight CPE products, are very efficient at high levels of filler (i.e. CaCO3>8 phr). The high molecular weight CPE impact modifier has a synergistic effect with high CaCO3 filler levels, boosting the impact strength of the final formulation. This effect is also seen at low temperatures, important in cold regions. This advantage has been exploited in the North American rigid PVC siding market; however, the European window profile market has kept CaCO3 levels at 5–8 phr. There is a lack of knowledge around high molecular weight CPE in comparison with newer AIM in highly filled formulations, especially on how the impact modifier affects toughness and plate-out. A range of impact modifiers has been studied, focusing on their effects on impact strength (at room and low temperatures) and plate-out in formulations with high filler levels. [ABSTRACT FROM AUTHOR]

In this article, we survey various non-contact, non-destructive testing methods by way of terahertz (THz) spectroscopy and imaging designed for use in various industrial sectors. A brief overview of the working principles of THz spectroscopy and imaging is provided, followed by a survey of selected applications from three industries—the building and construction industry, the energy and power industry, and the manufacturing industry. Material characterization, thickness measurement, and defect/corrosion assessment are demonstrated through the examples presented. The article concludes with a discussion of novel spectroscopy and imaging devices and techniques that are expected to accelerate industry adoption of THz systems. [ABSTRACT FROM AUTHOR]

In this paper, a novel optimization model is developed for heavy construction equipment. This approach investigates a complete range of engine operating points, considering fuel consumption and emission maps to accurately model fuel efficiency and level of emissions in different working conditions. As a case study, a tracked bulldozer is investigated on different terrains. The target of the optimization problem is defined as a specific digging or grading depth with minimum fuel consumption and emissions (unburned hydrocarbons, carbon monoxide, and nitrogen oxides) based on EU non-road diesel engine emission standard values. Interaction between the terrain and the bulldozer track is modeled using a semi-empirical method. Dry sand, clayey soil, and snow terrain are considered. The studied bulldozer is a Caterpillar D8T with 233 kW engine power and 8A type blade. The design variables are engine speed, transmission gear number, and throttle position. Genetic algorithm, a famous optimization method, is employed. In order to reduce computational costs, integer programming genetic algorithm is utilized. Due to the complexity of the problem, a constrained nonlinear optimization problem with combined-objectives is developed. Results show that the general trend of fuel consumption and emissions rise as the digging depth increases, as expected. However, this study indicates that the bulldozer traction and digging control can be effectively manipulated by controlling the engine operating point, characterized by engine speed and gear number, to obtain significant improvements in fuel consumption and reduction of exhaust emissions. The results also indicate that re-performing the optimizing problem for different terrain types leads to optimized fuel and emissions targets of up to 77%. • A novel nonlinear optimization model is developed for heavy construction equipment. • Engine operating points are studied considering fuel consumption and emission maps. • Terrain and bulldozer track interaction is modeled by a terramechanics method. • Digging depth is the optimization target with minimum fuel consumption and emission. • Re-performing the optimization for different terrains improves the target up to 77%. [ABSTRACT FROM AUTHOR]