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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]

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 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]

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]