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The construction industry accounts for approximately one-third of the total waste generation globally. With the United Nations projecting a population increase of 2 billion within the next three decades, there is a heightened demand for building stock, generating unprecedented volumes of construction and demolition waste (CDW). To combat this, circular economy strategies are purported to help alleviate the prevailing situation. But a number of challenges are jeopardizing their implementation in the construction industry and preventing from achieving the UN Sustainable Development Goals, net zero carbon and zero avoidable waste targets. This paper systematically analyzes 54 research articles, published in the past decade within major peer-reviewed English-language scholarly publications in the form of a systematic research review. In doing so, it aims to identify and classify the challenges that prevent improved CDW management by assimilating previous research results in support of a circular economy. The classification and analysis using a PESTLE model offers insights into gaps and differences between categories, as well as regions and countries. This initial step could contribute to a better understanding of these barriers, along with associated solutions, which could result in a significant reduction on the impact of construction activities, therefore facilitating the development of an effective circular economy in the sector.

Construction waste (CW) source reduction is a crucial strategy to address the sustainability issue of the construction industry. The economic benefit is a key factor affecting project decision-makers on whether to implement this strategy. However, limited studies analysed the cost–benefit of CW source reduction from a system dynamic perspective. Therefore, by considering the design and construction phase as a whole, this study constructed a system dynamics (SD) model based on the identification of the factors affecting the cost–benefit of CW source reduction to analyse the cost–benefit of CW source reduction. A residential building project in China’s Chengdu was used for the study case. The results show that the net benefit of CW source reduction is positive, and BIM implementation, design for standard material size, and building material storage are the three strategies to effectively improve the economic benefits of CW source reduction. Furthermore, the best investment level of CW source reduction was also determined. This study provides a model which can be used to simulate the cost–benefit under different implementation levels of reduction strategies and different investment levels in advance, thereby providing a reference for project decision-makers to plan CW source reduction.

Construction and demolition waste represents a growing environmental, social, and economic problem, and has become a priority for European and worldwide policies. The early quantification of construction waste is essential for the minimisation of its production and the improvement of waste management. This requires the development of design-based tools that enable a better understanding of the expected waste produced during the construction phase. Building Information Modelling (BIM) methodologies have gained recognition in the Architecture, Engineering, Construction, and Operations (AECO) sector, largely due to their capacity for data simulation, storage, and management during the building design phase. This study presents a software application, called WE-BIM Add-in, to quantify construction waste (CW) while designing the BIM model in Revit. A validated CW quantification model which enables waste types and quantities per building element to be predicted in detail according to the European List of Waste (LoW) is integrated into the Revit workflow. Design alternatives could be effortlessly simulated in real time to assist practitioners in decision-making during the early design stages. Two alternative structural systems of a Spanish residential building were compared: a reinforced concrete structure, Option 1 (O1), and a steel structure, Option 2 (O2). The results were obtained automatically: O2, in addition to reducing 56% of O1′s waste, would have increased the waste recycling rate by 49%; and displayed in Revit, thereby remaining consistent with those of other studies that compare prefabricated systems with in situ systems. This work provides a basis for future research into the automated estimation of construction waste in BIM which could become a useful tool in waste-prevention policies.

The scientific community has revealed the environmental benefits of recycling construction waste (CW) versus its disposal, and its contribution to circularity. The Life Cycle Assessment (LCA) method enables the environmental impact of CW management to be quantified and facilitates the comparison of recycling versus alternative disposal scenarios. However, due to its complexity, LCA is seldom used by technicians during the design phase, which constitutes a crucial stage in the prevention of environmental impacts. This paper therefore proposes an LCA-based tool, integrated into the Building Information Modelling (BIM) methodology, that helps designers to automate the environmental assessment of recycling versus disposal. The CW-LCA-BIM tool uses impact factors obtained from an LCA model applied to CW and was applied to the structural system of a building in Spain. Up to 99% of the non-hazardous waste was recyclable or reusable. The management of three types of recyclable waste was assessed: concrete (27.2 t), plastics (4.2 t), and steel (1.5 t). Recycling is shown to be the best option since it prevents 1.4 times (14.6 t) the emissions of the disposal scenario and saves 85 times (148.5 GJ) its energy consumption. This tool can be developed in other waste management systems and infrastructures. It can be useful both for designers for the reduction of the environmental impact of their buildings, and for policy managers for waste-prevention policies.

Global construction waste (CW) poses escalating environmental, social, and economic challenges. While New Zealand grapples with a dearth of research on optimal construction waste management (CWM) techniques, it stands to gain from the comprehensive practices employed in regions like Hong Kong. Drawing from the extensive literature on CWM practices in Hong Kong and other countries, this study seeks to furnish New Zealand’s construction professionals and policymakers with invaluable insights. Key findings illuminate the determinants of successful CWM, the motivations steering stakeholder behaviour towards CW reduction, the transformative potential of public policy, and innovative enhancement strategies. The research underscores the instrumental roles of green building and big data in CW curtailment, delving into the attendant challenges and rewards. By assimilating lessons from these international paradigms, New Zealand is poised to refine its CWM, catalysing a shift towards a more sustainable construction landscape.

The waste generation rate (WGR) is used to predict the generation of construction and demolition waste (C&DW) and has become a prevalent tool for efficient waste management systems. Many studies have focused on deriving the WGR, but most focused on demolition waste rather than construction waste (CW). Moreover, previous studies have used theoretical databases and thus were limited in showing changes in the generated CW during the construction period of actual sites. In this study, CW data were collected for recently completed apartment building sites through direct measurement, and the WGR was calculated by CW type for the construction period. The CW generation characteristics by type were analyzed, and the results were compared with those of previous studies. In this study, CW was classified into six types: Waste concrete, waste asphalt concrete, waste wood, waste synthetic resin, waste board, and mixed waste. The amount of CW generated was lowest at the beginning of the construction period. It slowly increased over time and then decreased again at the end. In particular, waste concrete and mixed waste were generated throughout the construction period, while other CWs were generated in the middle of the construction period or towards the end. The research method and results of this study are significant in that the construction period was considered, which has been neglected in previous studies on the WGR. These findings are expected to contribute to the development of efficient CW management systems.

The United States manufactured significant quantities of chemical weapons during the Cold War and the years prior. Because the chemical weapons are aging, storage constitutes an ongoing risk to the facility workforces and to the communities nearby. In addition, the Chemical Weapons Convention treaty stipulates that the chemical weapons be destroyed. The United States has destroyed approximately 90 percent of the chemical weapons stockpile located at seven sites. As part of the effort to destroy its remaining stockpile, the Department of Defense is building the Blue Grass Chemical Agent Destruction Pilot Plant (BGCAPP) on the Blue Grass Army Depot (BGAD), near Richmond, Kentucky. The stockpile stored at BGAD consists of rockets and projectiles containing the nerve agents GB and VX and the blister agent mustard. Continued storage poses a risk to the BGAD workforce and the surrounding community because these munitions are several decades old and are developing leaks. Due to public opposition to the use of incineration to destroy the BGAD stockpile, Congress mandated that non- incineration technologies be identified for use at BGCAPP. As a result, the original BGCAPP design called for munitions to be drained of agent and then for the munition bodies to be washed out using high-pressure hot water. However as part of a larger package of modifications called Engineering Change Proposal 87 (ECP-87), the munition washout step was eliminated. Effects of the Deletion of Chemical Agent Washout on Operations at the Blue Grass Chemical Agent Destruction Pilot Plant examines the impacts of this design change on operations at BGCAPP and makes recommendations to guide future decision making.

A microbial fuel cell coupled with constructed wetland (CW-MFC) was built to remove heavy metals (Zn and Ni) from sludge. The performance for the effects of substrates (granular activated carbon (GAC), ceramsite) and plants ( Iris pseudacorus , water hyacinth ) towards the heavy metal treatment as well as electricity generation was systematically investigated to determine the optimal constructions of CW-MFCs. The CW-MFC systems possessed higher Zn and Ni removal efficiencies as compared to CW. The maximal removal rates of Zn (76.88%) and Ni (66.02%) were obtained in system CW-MFC based on GAC and water hyacinth (GAC- and WH-CW-MFC). Correspondingly, the system produced the maximum voltage of 534.30 mV and power density of 70.86 mW·m −3 , respectively. Plant roots and electrodes contributed supremely to the removal of heavy metals, especially for GAC- and WH-CW-MFC systems. The coincident enrichment rates of Zn and Ni reached 21.10% and 26.04% for plant roots and 14.48% and 16.50% for electrodes, respectively. A majority of the heavy metals on the sludge surface were confirmed as Zn and Ni. Furthermore, the high-valence Zn and Ni were effectively reduced to low-valence or elemental metals. This study provides a theoretical guidance for the optimal construction of CW-MFC and the resource utilization of sludge containing heavy metals.

This study investigated the feasibility of large-scale utilizing calcareous wastes (CW) of Angoran lead and zinc mine as aggregates in mortar production with the maximum possible substitution of natural aggregates. The main goal was to produce mortar (concrete with fine aggregates as fine as sand or smaller) from Angoran mine's calcareous wastes for maintenance in its underground spaces. Compared to concrete, such mortars with better fluidity can enter narrow spaces more easily. In addition, it can be used to build various structures around the mine. Therefore, multiple samples were prepared by replacing 0% (as the control sample), 20%, 40%, 60%, 80%, and 100% of natural aggregates with CW. Subsequently, compressive strength, flexural strength, water absorption, slump, and TCLP tests were conducted on these samples. The results revealed that the mortar sample with 80% CW exhibited significantly higher compressive strength at 3, 14, 28, and 56 days compared to both the control sample and other samples. Specifically, the compressive strength of this sample reached 35.5 MPa at 56 days, representing an 18.4% increase over the control sample. This indicates that the hydration of cement and the growth of C-S–H gel were enhanced. Analysis of the workability and slump of the samples indicated that as the percentage of natural aggregate replaced by CW increased, the fluidity of the mortar slightly decreased. In addition to mechanical properties like compressive strength, environmental aspects like heavy metal stabilization are also very important. So, TCLP tests conducted on the four heavy metals lead, zinc, copper, and cadmium demonstrated that the released amounts of these elements from all the samples were below the EPA standard limits. These findings confirm the effective stabilization of heavy metals in mortar samples. A comparison of SEM images revealed that the mortar sample made with 20% CW (with minimum compressive strength) exhibited a higher presence of ettringite compared to the sample made with 80% CW (with maximum compressive strength) after 28 days.

This proceeding volume has been retracted from the publication because we found some solid reasons to believe that it has infringed our integrity criteria and now presents a risk for our journal and scholarly science in general. Different types of malpractice are involved, in particular citation manipulation and inappropriate references. We are extremely concerned by such malpractice which considerably impacts the image of our title and our Publisher’s reputation. For further details, please refer to our publishing ethics policies . If you have any questions, please contact us at contact@webofconferences.org See the retraction notice E3S Web of Conferences 505 , 00001 (2024), https://doi.org/10.1051/e3sconf/202450500001