Demolition waste recycling in China: New evidence from a demolition project for highway development

Impact assessment of construction waste policy intensity on environmental efficiency based on system generalized method of moments

With the acceleration of urbanization in recent years, China has witnessed large-scale construction across its provinces, generating massive amounts of construction waste that pose challenges to environmental protection and sustainable development. This study evaluated the impact of construction waste policy intensity on its environmental efficiency. Firstly, the content analysis method was used to analyze the construction waste policy text quantitatively. Second, this study constructed a slack-based measure (SBM) model based on data envelopment analysis (DEA), considering resource input and construction waste output to measure environmental efficiency. Finally, we built and tested an econometric model of how policies affect environmental efficiency using the system generalized method of moments (SYS-GMM). The findings indicate a non-linear U-shaped link between policy intensity and environmental efficiency. Among all five control variables, population density, urbanization level, and technological innovation enhance environmental efficiency, while economic development and highway density will lower it. This study advances the research on construction waste policies and offers some insights for the construction industry to pursue sustainable development.

Identifying and prioritizing sustainability indicators for China's assessing demolition waste management using modified Delphi-analytic hierarchy process method

Addressing the sustainability issues arising from construction and demolition waste management (DWM) has gained little traction due to the lack of incentives, stringent regulations, and systematic guidance. This study aims to empower systematic decision-making concerning DWM alternative selection by developing a sustainability assessment framework by coupling a modified Delphi method with the multicriteria decision analysis technique. First, the study identifies a comprehensive inventory of indicators across three dimensions of sustainability in the context of DWM. Next, the study combines a modified Delphi method with the analytic hierarchy process to validate and prioritize the selected sustainability indicators. For the first time, insights regarding the DWM sustainability indicators from China's construction industry practitioners' perspectives are elicited using a mixed method comprising online semistructured interviews and two rounds of questionnaire surveys. Experts participating in the research are mostly based in Guangzhou and Shenzhen, where local governments exhaust all efforts in promoting carbon-neutral and sustainable development. The findings reveal that eight sustainability indicators were regarded as the determinants for the sustainability performance of DWM, with the global warming potential (32%), energy efficiency (16.1%) and land use (13.5%) receiving the highest preference scores (weights) based on the experts' judgment. Notably, the economic factors like the total cost (6.54%) appeared not highly prioritized by the local experts as typically did in the previous studies from developing countries.

Evolutionary game model of construction enterprises and construction material manufacturers in the construction and demolition waste resource utilization

With the continuous advancement of urbanization, a huge amount of construction and demolition waste (CDW) is generated in large-scaled construction activities, which has aggravated the problem of environmental pollution, waste of resources and destruction of city appearance. In the context of waste-free city, the recycling of CDW can reduce environmental pollution and promote the sustainable development of a city. However, only 20-30% of CDW in the world is recycled, showing a low rate of global CDW utilization. In order to improve the utilization rate, this paper selects construction enterprises and construction material manufacturers as main participants, applies evolutionary game theory to construct an evolutionary game model on the two parties' decision-making behaviors in CDW recycling, and uses MATLAB to make a numerical simulation. The aim of the model is to analyze the influence of various factors on the parties' decision-making behavior evolution and propose strategies to promote CDW utilization. The study found that the stable state of the CDW resource utilization system mainly depends on the difference between revenue and costs, the initial strategy, and the strength of the external environment; for the government, a supervision strategy is found to be necessary, and the best supervision level is 0.6. In the early stage of resource utilization of CDW, subsidies to construction material manufacturers should be increased to improve their initial participation; public participation can effectively improve the efficiency of government supervision, and its optimal participation level is greater than or equal to 0.4; under weak supervision, government penalty increases alone cannot prevent construction enterprises from illegally disposing of CDW. Therefore, the greater the difference, the positive the initial strategy, and the stronger the external environment, the more the behavior of the two participants tends to be {participation, use}. The results show that the government should establish effective supervision mechanisms and legal systems, improve supervision hotlines and information platforms, encourage the public to participate in CDW management and supervision, set appropriate rewards and punishments, strengthen supervision and management levels, reduce supervision costs, and ensure the effectiveness of construction management to improve the efficiency of cooperation between construction enterprises and construction material manufacturers.

Construction and demolition waste management in Australia: A mini-review

Construction and demolition activities generate huge quantities of waste with substantial impacts on environment. This mini-review article covers the literatures relating to construction and demolition waste management practice in Australia. The Scopus search engine was used in literature search and 26 journal articles relating to construction and demolition waste management in Australia were targeted for analysis. Additionally, various government acts, regulations, policies, and strategy documents were collected and analyzed. This review indicated that the inconsistencies in legislation and landfill levies across states and territories contributed to the cross-jurisdiction waste movement. Given the stakeholders' attitude and project life cycle, this review reported that the design phase had the greatest potential to minimize waste and that the role of designers had been highlighted in various empirical studies. This review provides practitioners and academics with an understanding of the current construction and demolition waste management research in Australia and recommends directions for future research.

Minimizing Macro-Level Uncertainties for Quality Assurance in Reverse Logistics Supply Chains of Demolition Waste

In light of the increasing detrimental effects on sustainability, the reverse logistics supply chain (RLSC) has emerged as one of the remedies in the construction industry, whereby the bulk of demolition waste (DW) is returned into the production cycle. Quality assurance (QA) plays an important role in RLSCs, which needs an information-rich environment enriched with external stakeholders’ influence strategies. However, due to ineffective external stakeholders’ influence, useful information is not available, making macro-level uncertainties for QA. Given this, the current study aimed to identify the macro-level uncertainties for QA in the RLSC of DW. The study used a qualitative approach involving 21 semi-structured interviews representing five external stakeholder categories. The study found the regulatory uncertainties are the root causes that propagate through incentivizing and contractual uncertainties to influence QA in the RLSC. The external stakeholders could employ measures such as ‘reforming regulatory instruments’, ‘employing effective incentivizing schemes’ and ‘active involvement of forward supply chain actors’ to minimize uncertainties at their source. The external and internal stakeholders can use these findings as a roadmap to determine suitable measures to overcome macro-level uncertainties in the RLSC. Furthermore, the study paved an avenue to integrate stakeholder theory and organizational information processing theory (OIPT) in future research.

Stakeholder-Associated Factors Influencing Construction and Demolition Waste Management: A Systematic Review

Construction and demolition (C&D) activities generate a large amount of waste and have significant impacts on the environment. Thus, it is necessary to implement C&D waste management (WM), which requires the involvement of stakeholders and is influenced by a variety of factors. This study aims to undertake a systematic review of the stakeholder-associated factors influencing C&D WM. The Scopus search engine was used in a literature search, and two rounds of screening were performed. Only journal articles or reviews that were published in English after 2000 were used in this study. A total of 106 journal articles were reviewed. The review identified 35 stakeholder-associated factors influencing C&D WM and categorized them into six groups: regulatory environment, government and public supervision, advances in technologies, recycling market, knowledge, awareness, attitude, and behaviour of stakeholders, and project-specific factors. All the 35 factors are discussed in detail with considerations into relevant stakeholders. Although there have been studies focused on the factors influencing C&D WM, few have attempted to take stakeholders’ perspectives into consideration. This study expands the C&D WM literature by mapping the influential factors with relevant stakeholders and enables the practitioners to clearly understand their roles and responsibilities and make better informed decisions in the C&D WM process.

Construction and demolition wastes in Beijing: Where they come from and where they go?

Urbanization and related construction activities generate massive construction and demolition (C&D) waste, which poses considerable risks to the environment and human health. However, it is difficult to assess the significance of these issues without a quantitative understanding of spatial patterns of C&D waste generation (source), transportation (flow), and treatment (sink). This paper maps source, sinks, and flows of C&D waste by coupling a geographic information system and material flow analysis. The methodology is new in the field of C&D waste quantification at the city level, especially downscaling to 5 km × 5 km grids. The results showed that a total of 37.72 million metric tonnes (Mt) of C&D wastes were generated in Beijing, 2019, and ~72% of them were reused and recycled. In space, C&D waste generation in suburban and rural districts (28.73 Mt) was over three times more than that in the downtown area (8.99 Mt). However, the downtown area was the net source region and transported massive amounts of C&D waste to suburban and rural districts. In comparison, several suburban and rural districts had self-sufficient treatment capacity. Our study highlights that a series of C&D waste maps on multiple spatial scales are of great help to design effective policies for waste management by providing spatial details of magnitude and components, and explicitly recognizing primary source and sink areas in cities.