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Construction contractors and facility managers are being challenged to minimize the carbon footprint. Life cycle carbon‐equivalent (CO₂‐e) accounting, whereby the potential emissions of greenhouse gases due to energy expenditure during construction and subsequent occupation of built infrastructure, generally ceases at the end of the service life. However, following demolition, recycling of demolition waste that becomes incorporated into 2nd generation construction is seldom considered within the management of the carbon footprint. This paper aims to focus on built concrete infrastructure, particularly the ability of recycled concrete to chemically react with airborne CO₂, thereby significantly influencing CO₂‐e estimates.

CO₂‐e estimates were made in accordance with the methodology outlined in the Australian National Greenhouse Accounts (NGA) Factors and were based on the energy expended for each life cycle activity from audited records. Offsets to the CO₂‐e estimates were based on the documented ability of concrete to chemically react with airborne carbon dioxide (“carbonation”) and predictions of CO₂ uptake by concrete and recycled concrete was made using existing predictive diffusion models. The author's study focused on a built concrete bridge which was demolished and recycled at the end of the service life, and the recycled concrete was utilized towards 2nd generation construction. The sensitivity of CO₂‐e and carbonation estimates were tested on several different types of source demolition waste as well as subsequent construction applications using recycled concrete (RCA). Whole‐of‐life CO₂‐e estimates, including carbonation of RCA over the 1st and 2nd generations, were estimated and contrasted with conventional carbon footprints that end at the conclusion of the 1st generation.

Following demolition, CO₂ capture by RCA is significant due to the more permeable nature of the crushed RCA compared with the original built infrastructure. RCA also has considerably greater exposed surface area, relative to volume, than a built concrete structure, and therefore more highly exposed surface to react with CO₂: it therefore carbonates more comprehensively. CO₂‐e estimates can be offset by as much as 55‐65 per cent when including the contribution of carbonation of RCA built within 2nd generation infrastructure. Further offsets are achievable using blended fly ash or slag cement binders; however, this study has focused on concrete composed of 100 per cent OPC binders and the effects of RCA.

Construction project estimates of life cycle CO₂‐e emissions should include 2nd generation applications that follow the demolition of the 1st generation infrastructure. Life cycle estimates generally end at the time of demolition. However, by incorporating the recycled concrete demolition waste into the construction of 2nd generation infrastructure, the estimated CO₂‐e is significantly offset during the 2nd generation life cycle by chemical uptake of CO₂ (carbonation). This paper provides an approach towards inclusion of 2nd generation construction applications into whole‐of‐life estimates of CO₂‐e.

The growth of the Chinese economy has resulted in a significant increase in construction and demolition waste (CDW), and regional differences in CDW generation are gradually increasing. The purpose of this study is to investigate the regional differences in CDW generation and the driving factors that influence CDW generation in different areas of China. To provide a systematic advisement for local governments to select the appropriate policy, reduce CDW generation.

The generation of CDW was calculated by region, based on the area estimation method, from 2005 to 2018. The relationship between CDW generation and economic development, and the driving factors of CDW generation in different regions of China, was investigated using the environmental Kuznets curve (EKC) model and the STIRPAT theoretical model.

CDW generation of China increased at the average annual growth rate of 10.86% from 2005 to 2018. The main areas of CDW generation were concentrated in the eastern and central regions, while the proportion of CDW generation in the northeast region decreased gradually, and the changes varied significantly across different regions. The EKC between CDW generation and economic development was established for the whole country, North China, Northeast China, East China, Central South China, Southwest China and Northwest China. Three main factors based on the STIRPAT theoretical model were identified and explained into a framework to reduce CDW generation. The results provided a useful theoretical basis and data support guide for devising effective policies and regulations for the Chinese context.

The findings from this study can ultimately support policymakers and waste managers in formulating effective policies for waste management strategies and CDW-specific legislation. Additionally, it can help the coordinated reduction of CDW generation across regions in China and can support construction enterprises (in their development strategies), similar developing economies and foreign firms planning to operate in China.

This study contributes to the field through the STIRPAT model on driving factors of CDW generation in the Chinese context, in different regions.

The generation of construction and demolition waste in China is a pressing need to be minimized in order to alleviate the environmental burden. The effectiveness of implementing construction and demolition waste management in this economy, however, is very limited due to various barriers. Therefore, this paper aims to explore the major obstacles to managing construction and demolition waste in China.

The views from Chinese practitioners were collected via a questionnaire survey. The respondents were invited to rate a total of 16 obstacles that hinder the effective implementation of construction and demolition waste management as gleaned from previous literature and six semi‐structured interviews. The results of the questionnaire were analyzed by ranking analysis and factor analysis.

The findings show that “lack of a well‐developed waste recycling market”, “insufficient regulation support” and “waste reduction does not receive sufficient attention in construction design” are perceived as the three barriers of most importance. Furthermore, the 16 obstacles could be grouped into five underlying components including: component 1 – weak awareness and inadequate training, component 2 – insufficient support of the authority, component 3 – economic consideration, component 4 – immature market and component 5 – barriers related to site activity.

Based on the findings, industry practitioners' understandings about the barriers to better performing construction and demolition waste management in China can be deepened. Furthermore, the results also provide useful information for developing strategies to improve the performance of construction and demolition waste management in China.

Major obstacles to improving the performance of construction and demolition waste management in China are identified and analyzed in this study.

The purpose of this paper is to develop a novel tool to support decision making for enhanced demolition process efficiency and material waste sortability through computerised 4D motion workflow simulation.

A time-lapse evaluation model was developed to classify and estimate the impact of building demolition processes and material waste recovery. The dynamic assessment of demolition, collision and mechanical impact was measured through computerised 4D motion game and physics engines. Waste recovery and treatment complemented the simulation algorithm. The simulation of the information workflow was tested through case study using two demolition strategies.

The simulation successfully estimated the efficiency and efficacy of the different demolition strategies. Thus, simulation results can potentially support better decision making related to the definition of demolition strategies associated with recycling and re-use targets.

The simulation was limited to a simple machine-led demolition strategy. Further research is required to understand the impact of complex machine mechanic movements and processes on complex building fabrics.

Modelling and evaluating the demolition process and its impact on material waste recovery with a time dimension is novel. The comparative analysis of quantitative data allows demolition professionals to find optimal and more sustainable demolition solutions and more efficient and safer implementation on site. It also contributes to a better understanding of the relationship between demolition strategy and waste sortability. This research represents a significant advancement in applied computing for building demolition waste recycling and notably, it improves the quality of information available in the definition of building demolition strategies.

This paper aims to explore UAE's transition towards circular economy (CE) through construction and demolition waste (CDW) management in the pre-construction stage. The extent of circularity is assessed by five key aspects of CE, such as policies and strategic frameworks, design for waste prevention, design for disassembly or deconstruction, use of prefabricated elements and CDW management plans.

Multiple case studies were conducted in the context of the Dubai construction industry (UAE). Three significant and unique construction projects were selected as the cases. Semi-structured interviews were carried out to collect data, and the thematic analysis technique and NVIVO 12 software were used for data analysis.

Findings reveal several positive initiatives towards CE in the UAE context; yet it is identified that the transition is still at the initial stage. Selected case studies, the best-case scenarios of UAE (i.e. influential cases), demonstrated adequate measures in relation to four key CE aspects out of five. For instance, (a) policies and strategic frameworks such as lean standards, green building standards and standards developed by the local authorities, (b) design for waste prevention (e.g. adherence to the 3R principle, and construction planning with BIM), (c) use of prefabricated elements and application of innovative construction technologies (e.g. 3DPC, DfMA) and (d) CDW management planning such as 3R principle were evident. However, the selected cases hardly showcase designing for disassembly or deconstruction.

The existing CDW practices are mostly conventional, as most constructions in UAE are procured through conventional building materials and methods. Therefore, there is a necessity of encouraging CE principles in CDW management. Even though the transition towards CE was evident in four key CE aspects out of five, the UAE construction industry has yet to adopt more effective CE-based CDW management practices to accelerate the circularity. Hence, it is necessary to enforce standard waste management guidelines, including the 3R principle, to standardise CDW management in UAE and encourage construction practitioners to adhere to CE principles.

The findings of this study provide valuable insights for decision-making processes around CDW management towards a CE. This paper contributes to the literature by bridging the CE concept with CDW management in the pre-construction stage. The study provides insights for industry practitioners for planning CE in terms of policies and strategic frameworks, CDW management planning, construction planning and application of innovative construction technologies.

Construction and Demolition (C&D) Waste Management (WM) poses significant challenges in Sri Lanka, contributing to environmental degradation and resource depletion. To address these issues, this study explores the application of Circular Economy (CE) strategies in minimising waste generation and optimising resource utilisation in Sri Lankan construction industry. The research focuses on the construction and building renovation and use and operate stages of the building project life cycle, recognising their significance in waste generation and resource consumption.

The research employed a qualitative approach, utilising the Delphi technique through three rounds of expert interviews. Seventeen experts were involved in the first round, followed by fifteen in the second round, and twelve in the final round. The collected data was analysed using manual content analysis methods.

The research findings revealed fifteen C&D WM issues in the construction and building renovation stage in Sri Lanka, along with suitable strategies to overcome each of them. Similarly, eight C&D WM issues were identified for the use and operate stage of the building, and corresponding strategies were provided to address each issue. By adopting CE strategies such as modular design and material reuse, construction projects can optimise the project's timeline, cost, and quality factors. These strategies enable efficient resource allocation, reduce waste generation, and contribute to the overall sustainability of the project. The impact of CE strategies on mitigating these issues within the project management iron triangle was also discussed.

This paper entails delving into how construction, building renovation, and operation stages of a building's life cycle intersect with CE strategies, which profoundly influence operational efficiency and long-term sustainability. By incorporating principles such as energy efficiency, water conservation, and circular product design, the paper illuminates how these strategies facilitate decreased energy usage, enhanced resource management, and diminished waste production throughout the building's lifespan.

The purpose of this study is to explore the multifaceted challenge of managing construction and demolition waste within the context of the Jordan construction industry.

Using data sourced through desk research, interviews and questionnaires, this study examines the principal causes of increased volumes of construction and demolition waste, as well as the obstacles to both developing and implementing better waste management strategies.

This study identifies multiple causes of issues related to waste management and barriers to developing and implementing solutions and concludes by recommending a holistic approach to this multifaceted problem. A lack of adequate construction waste management infrastructure, regarding both physical facilities and regulations, was highlighted as the key challenge.

The accumulation of waste that results from construction and demolition activity, and activities characterized by unsustainable utilization of raw materials and inefficiency are a global issue. The challenge of effectively managing construction waste is importantly tied to factors including the availability of the necessary infrastructure; economic conditions; and the scarcity of skilled laborers, among others.

This study focuses on the Jordan construction industry, which is so far not very well researched. By building upon previous studies, this study supports further research to illuminate the causes of waste and the barriers to better management, an issue that is not only a pillar of progress at the country level but also key for a sustainable development in general.

Lean management has been used in various constructions around the world for more than a quarter of a century, and it is an important factor in the construction of new projects. In relation to demolition management, only standards and codes and general principles of demolition of specific buildings were evaluated. The purpose of this study is providing relation between lean management on demolition processes of municipality buildings evaluated.

This study investigates the lean demolition of demolished and renovated buildings in a metropolitan area that can be extended to all cities. In the first stage, the effective factors in the demolition of the building based on lean management were identified through a valid questionnaire based on the valid Delphi approach. Social, economic and environmental considerations were considered in designing the appropriate questionnaire.

The modified approach between the fuzzy method and partial least squares was used to evaluate important variables. All of the modified processes were developed in MATLAB by the authors of this paper. The results show that customer-focused degradation parameter has the weakest effect and waste removal variable has the most effect on lean management.

Statistical results show that there is no significant difference between the effect of lean management on variables such as demolition time, quality and type of construction (p < 0.05).

The purpose of this research is to address the existing gap in the study of construction and demolition waste (C&DW) by focusing on its impact on human health throughout the entire life cycle. And this research provides a comprehensive assessment model that incorporates the release of gaseous pollutants and particulate matter during the whole life cycle of C&DW, thereby contributing to a more holistic understanding of its impact on human health.

The research was conducted in two stages. Firstly, the quantitative model framework of pollutants emitted by C&DW was established. Three types of pollutants were considered, namely nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and inhalable particulate matter (PM10). Second, disability-adjusted life year (DALY) and willingness to pay (WTP) assessments were used to provide a monetary quantified health impact for pollutants released by C&DW.

The results show that the WTP value of PM10 is the highest among all pollutants and 8.68E+07 dollars/a, while the WTP value in the disposal stage accounts for the largest proportion compared to the generation and transportation stage. These findings emphasize the importance of PM10 and C&DW treatment stage for pollutant treatment.

The results of this study are of great significance for the management department to optimize the construction management scheme to reduce the total amount of pollutants produced by C&DW and its harm to human health. Meanwhile, this study fills the gap in existing research on the impact assessment of C&DW on human health throughout the whole life cycle, and provides reference and basis for future research and policy formulation.

The concept of Circular Economy (CE) has gained significant traction in addressing the issue of Construction and Demolition (C&D) waste, which is generated because of global urbanisation and urban renewal. Therefore, this research aims to explore the applicability of CE strategies to minimise the C&D Waste Management (WM) issues in Sri Lanka considering the preconstruction stage of the building project.

The research adopted a qualitative approach, using three expert interview rounds with the Delphi technique. In each round, 17, 15 and 12 experts were involved. A manual content analysis method was used to analyse the collected data.

Findings uncovered effective strategies in CE to address the 14 issues within C&D WM and its effects on the project management iron triangle in Sri Lanka. Integrating CE strategies within the construction sector to tackle C&D WM issues can significantly contribute to establishing a more sustainable, robust and resource-conscious built environment. By adopting CE strategies such as design for adaptability of existing buildings and design for disassembly, construction projects can optimise the project's timeline, cost and quality factors.

This will help to minimise the demand for virgin materials and reduce the volume of waste generated. Using recycled materials also helps close the loop of the materials cycle, thereby contributing to the CE. Also, this research contributes uniquely by offering practical, context-driven solutions that align with Sri Lanka’s construction sector.