A Conceptual Model for Assessing Circularity Potential of Building Materials at the Product Manufacturing Stage

The construction industry presently accounts for 30% of natural resource extraction and 25% of solid waste generation. The prevailing economy is “Linear” which is summarised as take-makedispose. On the contrary, the “circular economy” model is a systematic model to restore, regenerate and expand the lifecycle of materials. Most of the existing circularity assessment methods are focused on the end-of-life wastage of building materials while neglecting resource consumption and wastage at the product manufacturing stage. Further, these methods only consider direct material flows for assessing the circularity potential of building materials and overlook the indirect material flows associated with product manufacturing. There is a need to develop metrics to assess the circularity performance of building materials more holistically. Therefore, this study proposes a conceptual model to assess the circularity potential of building materials by analysing both direct and indirect material flow processes of the product manufacturing stage including raw material extraction, transportation, and manufacturing. The method used to design the conceptual model includes a comprehensive literature review in two stages. First, the existing circular assessment methods are reviewed to identify the methods used for assessing the circularity potential of building materials. Secondly, the circularity options are explored to develop the circularity metrics. According to the findings of this study, in the absence of a comprehensive method to assess the circularity potential of building materials, the life cycle assessment and material flow analysis are the most prominent circularity assessment methods used. Furthermore, circularity options such as industrial waste (by-products), biodegradability, biofuels, renewable energy, reusability, recoverability, recyclability and product life span are identified as the circularity metrics for building materials at the product manufacturing stage

A Conceptual Model for Assessing Circularity Potential of Building Materials at the Product Manufacturing Stage

The construction industry presently accounts for 30% of natural resource extraction and 25% of solid waste generation. The prevailing economy is “Linear” which is summarised as take-make dispose. On the contrary, the “circular economy” model is a systematic model to restore, regenerate and expand the lifecycle of materials. Most of the existing circularity assessment methods are focused on the end-of-life wastage of building materials while neglecting resource consumption and wastage at the product manufacturing stage. Further, these methods only consider direct material flows for assessing the circularity potential of building materials and overlook the indirect material flows associated with product manufacturing. There is a need to develop metrics to assess the circularity performance of building materials more holistically. Therefore, this study proposes a conceptual model to assess the circularity potential of building materials by analysing both direct and indirect material flow processes of the product manufacturing stage including raw material extraction, transportation, and manufacturing. The method used to design the conceptual model includes a comprehensive literature review in two stages. First, the existing circular assessment methods are reviewed to identify the methods used for assessing the circularity potential of building materials. Secondly, the circularity options are explored to develop the circularity metrics. According to the findings of this study, in the absence of a comprehensive method to assess the circularity potential of building materials, the life cycle assessment and material flow analysis are the most prominent circularity assessment methods used. Furthermore, circularity options such as industrial waste (by-products), biodegradability, biofuels, renewable energy, reusability, recoverability, recyclability and product life span are identified as the circularity metrics for building materials at the product manufacturing stage

The impact of occupants’ behaviours on building energy analysis: A research review

Over the past 15 years, the evaluation of energy demand and use in buildings has become increasingly acute due to growing scientific and political pressure around the world in response to climate change. The estimation of the use of energy in buildings is therefore a critical process during the design stage. This paper presents a review of the literature published in leading journals through Science Direct and Scopus databases within this research domain to establish research trends, and importantly, to identify research gaps for future investigation. It has been widely acknowledged in the literature that there is an alarming performance gap between the predicted and actual energy consumption of buildings (sometimes this has been up to 300% difference). Analysis of the impact of occupants’ behaviour has been largely overlooked in building energy performance analysis. In short, energy simulation tools utilise climatic data and physical/ thermal properties of building elements in their calculations, and the impact of occupants is only considered through means of fixed and scheduled patterns of behaviour. This research review identified a number of areas for future research including: larger scale analysis (e.g. urban analysis); interior design, in terms of space layout, and fixtures and fittings on occupants’ behaviour; psychological cognitive behavioural methods; and the integration of quantitative and qualitative research findings in energy simulation tools to name but a few

The Influence of Space Layout Design on Occupant’s Energy Behaviour

In the past 15 years, the calculation of energy consumption in buildings has become more and more critical due to growing scientific and political concerns to respond to the challenges of global warming and climate change. The estimation of energy demand in buildings is now often a required process during the design stages. Yet, there is a considerable discrepancy between the predicted and actual energy consumption in buildings due to occupantsÕ energy consumption activities. OccupantsÕ presence and their interactions with building systems play a significant role in buildingÕs energy consumption; however, it has been overlooked in building energy predictions. Different studies have been performed with the aim to better understand the parameters affecting occupantÕs energy behaviour with special focus on climatic, economics, regulations and social/personal aspects. Interior design of the space, too, has various impacts on behaviours of occupants and their interactions with building systems which affects the energy consumption of buildings. Space layout is a feature within interior design of space which influences occupantsÕ movement and choices of intentional behaviours. This paper highlights a gap in the knowledge by introducing Òspace layoutÓ features as an influential factor on occupantÕs energy behaviours and propose an analytical method to study the impact of the space layout on occupantsÕ energy behaviours. Understanding the impact will help designers influence the sustainable behaviour through the design of interior spaces

Metrics development and modelling the mixed reality and digital twin adoption in the context of Industry 4.0

PurposeThis paper aims to examine the current technology acceptance model (TAM) in the field of mixed reality and digital twin (MRDT) and identify key factors affecting users' intentions to use MRDT. The factors are used as a set of key metrics for proposing a predictive model for virtual, augmented and mixed reality (MR) acceptance by users. This model is called the extended TAM for MRDT adoption in the architecture, engineering, construction and operations (AECO) industry.Design/methodology/approachAn interpretivist philosophical lens was adopted to conduct an inductive systematic and bibliographical analysis of secondary data contained within published journal articles that focused upon MRDT acceptance modelling. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) approach to meta-analysis were adopted to ensure all key investigations were included in the final database set. Quantity indicators such as path coefficients, factor ranking, Cronbach’s alpha (a) and chi-square (b) test, coupled with content analysis, were used for examining the database constructed. The database included journal papers from 2010 to 2020.FindingsThe extant literature revealed that the most commonly used constructs of the MRDT–TAM included: subjective norm; social influence; perceived ease of use (PEOU); perceived security; perceived enjoyment; satisfaction; perceived usefulness (PU); attitude; and behavioural intention (BI). Using these identified constructs, the general extended TAM for MRDT in the AECO industry is developed. Other important factors such as “perceived immersion” could be added to the obtained model.Research limitations/implicationsThe decision to utilise a new technology is difficult and high risk in the construction project context, due to the complexity of MRDT technologies and dynamic construction environment. The outcome of the decision may affect employee performance, project productivity and on-site safety. The extended acceptance model offers a set of factors that assist managers or practitioners in making effective decisions for utilising any type of MRDT technology.Practical implicationsSeveral constraints are apparent due to the limited investigation of MRDT evaluation matrices and empirical studies. For example, the research only covers technologies which have been reported in the literature, relating to virtual reality (VR), augmented reality (AR), MR, DT and sensors, so newer technologies may not be included. Moreover, the review process could span a longer time period and thus embrace a fuller spectrum of technology development in these different areas.Originality/valueThe research provides a theoretical model for measuring and evaluating MRDT acceptance at the individual level in the AECO context and signposts future research related to MRDT adoption in the AECO industry, as well as providing managerial guidance for progressive AECO professionals who seek to expand their use of MRDT in the Fourth Industrial Revolution (4IR). A set of key factors affecting MRDT acceptance is identified which will help innovators to improve their technology to achieve a wider acceptance.</jats:sec

A Conceptual Model for Assessing Circularity Potential of Building Materials at the Product Manufacturing Stage

The construction industry presently accounts for 30% of natural resource extraction and 25% of solid waste generation. The prevailing economy is “Linear” which is summarised as take-make dispose. On the contrary, the “circular economy” model is a systematic model to restore, regenerate and expand the lifecycle of materials. Most of the existing circularity assessment methods are focused on the end-of-life wastage of building materials while neglecting resource consumption and wastage at the product manufacturing stage. Further, these methods only consider direct material flows for assessing the circularity potential of building materials and overlook the indirect material flows associated with product manufacturing. There is a need to develop metrics to assess the circularity performance of building materials more holistically. Therefore, this study proposes a conceptual model to assess the circularity potential of building materials by analysing both direct and indirect material flow processes of the product manufacturing stage including raw material extraction, transportation, and manufacturing. The method used to design the conceptual model includes a comprehensive literature review in two stages. First, the existing circular assessment methods are reviewed to identify the methods used for assessing the circularity potential of building materials. Secondly, the circularity options are explored to develop the circularity metrics. According to the findings of this study, in the absence of a comprehensive method to assess the circularity potential of building materials, the life cycle assessment and material flow analysis are the most prominent circularity assessment methods used. Furthermore, circularity options such as industrial waste (by-products), biodegradability, biofuels, renewable energy, reusability, recoverability, recyclability and product life span are identified as the circularity metrics for building materials at the product manufacturing stage