In recent decades, global urbanisation has accelerated human population expansion, requiring more material resources. Construction uses 32% of natural resources (Yeheyis et al., 2012). However, this figure is lower than in the 1990s (40%) (Rees, 2010); it is estimated that over 75% of building waste has a residual value and is not presently utilised or recycled. Insufficiently integrated waste management framework (Yeheyis et al., 2012).
In general, construction and demolition wastes are nothing that is no longer usable due to building, restoration, or destruction. Most of the time, such garbage is dumped. Construction and demolition trash represents 30% of worldwide waste production (Papargyropoulou et al., 2011), with about 35% of construction and demolition waste deposited in landfills yearly (Menegaki and Damigos, 2018). The construction sector has a substantial environmental effect due to natural resources, energy consumption, and trash creation.
This is because the linear economic paradigm depends on taking, manufacturing, and discarding. Using energy-intensive equipment, raw materials are taken from natural resources and processed into building materials. Because most building materials cannot be deconstructed, they are thrown into a landfill or burnt (Mangialardo and Micelli, 2018). The negative repercussions of construction and demolition waste handling include environmental damage and public health (Lu and Yuan, 2012). This scenario necessitates an efficient framework to minimise pollution, climate change, and resource depletion (Yeheyis et al., 2012),7]. Concrete, wood, bricks, Glass, steel, and other rejected materials are often found in construction and demolition trash (Solís-Guzmán et al., 2009). Due to the vast construction and demolition waste generated each year, trash must be handled sustainably. Traditional environmental mitigation measures, such as linear Economy, have been inefficient. For sustainable development, the term Circular Economy has arisen as a unique method to decrease negative environmental impacts while increasing economic growth. The Circular Economy is a unique reformative framework that helps optimise raw material use and guarantees material value throughout its lifespan (Bilal et al., 2020). Circular Economy also reduces trash output and conserves natural resources. This technique shows that everything created can be recycled, reconditioned, or utilised. In their conclusion, Hossain et al. (Hossain et al., 2020) stated that employing Circular Economy for construction and demolition waste would improve sustainable resources, promote material efficiency by recycling/reusing construction waste, and reduce wasteful waste generation and disposal. Generally, the Circular Economy tries to repurpose materials that would otherwise be dumped into landfills in the construction business.
Different dimensions must be well understood to properly apply Circular Economy in a construction business. Ghisellini et al. studied the costs and advantages of the Circular Economy in the building and demolition industry. Lederer et al. used a material flow analysis to establish how a Circular Economy may reduce raw mineral imports for the building industry in Vienna. They discovered that reusing/recycling building minerals might cut imports by 32%. Although various efforts have been made to recycle or recover construction and demolition waste, little research has been done on the viability of including a Circular Economy in the current built environment. Unlike small and medium-sized building projects, large-scale CE applications pose significant obstacles. Combining novel technologies, such as BIM (Building Information Modelling), with Circular Economy might alleviate the issues in large-scale built environments. Several techniques have been suggested to help the building industry migrate to Circular Economy. Employing sustainable and durable materials, designing for disassembly, using modular and prefabricated pieces, and developing recovery methods [10,16]. However, little study has been done so far on the above methodologies.
This assessment will present a distinct viewpoint on how construction and demolition waste may be repurposed by adopting a Circular Economy strategy. Unlike the linear Economy, recovering or reusing resources requires additional stages, which means more obstacles. This research will explore the problems and limitations of implementing a Circular Economy for construction and demolition waste from a fresh perspective while minimising environmental consequences and reducing carbon emissions. The prospective usage of several materials that have proved helpful in building (especially concrete) will next be discussed. Also, this research provides a theoretical framework to encourage better use of recycled materials in the establishment or for other services.
Materials and Methods
This study’s approach has two primary stages. A systematic review was done to identify and synthesise scientific evidence in the first step. This method collects all essential research evidence. The most extensive scientific database, Science Direct, gathered relevant material for the systematic review. Keywords included “construction and demolition”, “waste”, “construction”, “circular economy”, “framework”, “climate change”, “carbon emissions”, etc. The Boolean operators (AND) and (OR) were employed to retrieve relevant articles. A few examples include “circular economy” AND “framework,” “construction and demolition waste” AND “waste,” “construction and demolition” AND “strategies,” and so on. The search was restricted to 2005–2021, with most articles from the past five years. This aimed to guarantee the retrieval of unique ideas and research concepts that were relevant and original. The benefit of this work above prior publications is that it discusses the relevance of environmental repercussions based on construction and demolition waste.
English is a worldwide lingua franca and is commonly used for communication. Similarly, most of the sources included in this study were peer-reviewed studies in reputable, well-indexed journals. Some of the references came from citations in the literature. With this framework, early adoption of this successful strategy may be achieved.
Background Information
Waste
Garbage is an unavoidable by-product of production and usage, whether an industrial by-product or demolition waste. However, owing to pollution, resource depletion, landfill site shortages, and climate change, academics have started investigating society’s role in waste reduction [17,18].
Seadon argues that society’s ‘mine-build-discard’ mentality is unsustainable. According to the essay, unsustainable civilisations inevitably collapse. Thriving communities recognise the value of limited resources, utilise them responsibly, and appreciate the surrounding environment. It is dynamic in all aspects, notably productivity, and uses scarce resources responsibly and effectively.
Globally, the quantity of garbage created each year is frightening. The global production of municipal solid waste was 2.02 billion metric tonnes in 2016 and is expected to rise to 3.4 billion metric tonnes by 2050 (Tiseo, 2021). A 70% rise in worldwide garbage output is estimated if the existing system is maintained. To solve this situation, the world community must work together to safeguard the future prosperity of our children.
The New Zealand construction sector was expected to rise 70% by 2029 before the COVID-19 pandemic. This means more horizontal infrastructure projects for New Zealanders, which means more jobs (Harman, n.d.). As a result, building and demolition trash, which accounts for around half of New Zealand’s landfill garbage, is expected to rise, possibly straining the country’s waste management system. Recycling waste materials is one technique New Zealand’s construction sector may use to decrease its environmental impact. Concrete is one material that has been shown to benefit from trash. According to Tavakoli et al. (Tavakoli, Hashempour and Heidari, 2018), concrete is the most significant building material nowadays. He also claims that employing waste materials in concrete may considerably lessen the negative environmental consequences of concrete.
Concepts and Foundations of Circular Economy
Developing urban infrastructure has made sustainability a popular term and a worry (Anastasiades et al., 2020). As a result, pollution and environmental damage increase (Jhatial et al., 2020). Sustainability is vital in every construction project since it helps the project and the environment. Thus, a popular definition of sustainable development is the certainty that a project meets current requirements without jeopardising future demands (Anastasiades et al., 2020). Sustainability has three pillars: planet, people, and profit. The planet’s ecosystem and environmental conditions are vital, but people’s demands should be met to maximise profit within limited resources. Sustainable development seeks to make growth socially, ecologically, and economically feasible, tolerable, and equitable.
The concept of Circular Economy arose from the desire to raise awareness about the environmental damage caused by using and wasting raw resources. The Circular Economy is being investigated as a potential solution for natural resource depletion. The Circular Economy idea grew out of the 3Rs (Reduce-Reuse-Recycle). The 4R framework focuses on reducing, reusing, recycling, and recovering raw materials (Anastasiades et al., 2020). Unlike in the linear Economy, natural materials in the Circular Economy are mended, recycled, and refurbished to be used in other processes. Thus, a Circular Economy’s principles include not buying surplus raw materials, changing design standards, and minimising, reusing, and recycling trash. Such approaches effectively recycle, decrease waste, and prevent global environmental damage.
Construction Waste
Construction waste is categorised based on its origin or type. The writers defined trash as physical (residual debris) and non-physical (waste) (time overruns and cost overruns). Figure 2 investigates building waste sources. As indicated in Figure 2, building debris may be classified as either artificial or natural. Artificial sources include design, procurement, material handling, operation, residue, and other sources (ElHaggar, 2007). construction and demolition waste materials are valuable and might be repurposed for concrete buildings. In concrete, the majority may be recycled as coarse or fine aggregate (Ulsen et al., 2013). Metals (6%), organic garbage (2%), Glass and hazardous materials (2%), and miscellaneous (5%) (Ghorbanian et al., 2017).
Figure 3 shows the tonnes of building trash generated in major European nations and New Zealand. Construction trash is a significant contributor in Denmark, France, Ireland, and Germany. Poland, Lithuania, Bulgaria, Greece, Slovakia, Hungary, and New Zealand generated the most minor building trash (Forbes, 2018). Construction and demolition waste accounts for over half of New Zealand’s yearly trash; hence, waste reduction efforts must be heavily engaged (Ghorbanian et al., 2017). However, 2019 Auckland City Council research on the diversion of demolition trash indicated that recycling would still have substantial advantages (Rohani et al., 2019). The research focused on the cost-benefit analysis of reusing demolition trash for new dwellings. Opt A, a moderate deconstruction technique that emphasises partial trash recovery and recycling, or Opt B, an intense deconstruction approach that emphasises the two highest levels of the hierarchy. While the developers would only break even, the net benefits to society were significant for both choices (A: NPV = $6.97 m, B: NPV = $14.46 m). Employers earned skills and experience through on-the-job training, while employees got skills and expertise by reusing building materials. While reducing and reusing were proven to be better for society, recycling was also helpful. For many materials, recycling is the sole option. Hence it is an integral waste reduction approach worth exploring.
Waste Minimisation in the Circular Economy
The core of the Circular Economy is reducing waste in landfills by reusing rejected materials in various ways. It is a 4R approach concentrating on Reduce-Reuse-Recycle-Recover raw material operations (Anastasiades et al., 2020). Less acquisition of raw materials means less GHG emissions, which helps the Economy and the environment. Moreover, reducing trash creation lowers the harmful consequences of garbage generation on our living environment.
Several studies have examined the economic viability of decreasing trash. This effort focuses on reducing construction and demolition waste, the leading contributor to landfills worldwide (Osmani and Villoria-Sáez, 2019). A cost-benefit analysis conducted in Malaysia in 2006 revealed reducing construction and demolition waste is possible with a 2.5% net profit (Begum et al., 2006). This research examined the costs and advantages of reducing trash on a Malaysian construction site. The study showed several immediate benefits, including reduced purchase costs from reusing and recycling goods, reduced garbage collection and transport costs, and reduced disposal charges. Intangible advantages include decreased responsibility for environmental issues or worker safety, loosened soil and groundwater pollution risk, and better public perception of the ecological problems—direct expenditures for collection and separation, equipment purchases, storage, and transportation. Intangible expenses included worker health risks and negative externalities like noise and odour. According to Auckland City Council research, less waste is economically viable and has many unquantifiable advantages. According to both studies, the rise in wastage levies might push construction businesses to adopt better waste reduction measures.
An independent researcher did a cost-benefit study to evaluate the waste reduction hypothesis (Ghorbanian et al., 2017). The project included building a complicated model of a waste chain that appropriately represented society’s trash. This conceptual model stresses the complexity of waste reduction and explains prior global waste reduction challenges. According to the model, a high waste tax would increase net benefits for construction businesses and society, but it would also encourage the general people to dump their garbage unlawfully. It was decided that stiffer punishments should be implemented to counteract this issue. It was discovered that under the four billing systems, the expenses initially surpassed the benefits, but by the 11th month, the benefits started to outweigh the costs. The high-charge schemes also encouraged contractors to start trash management early, making it more effective. The net advantages of reduced charge schemes increased considerably when the regulation was tightened. To be effective, trash charges must be more than 76 yuan/ton (NZD 15.50).
Waste reduction for contractors has been economically beneficial, as has waste minimisation for recycling organisations. One research looked at the economics of recycled concrete aggregate (Tam, 2008). The cost-benefit study included both existing and concrete recycling methods for waste disposal. Using concrete debris as aggregates instead of dumping it in landfills may assist the building sector (Tam, 2008). The research indicated a $30,916,000 annual net gain and reduced resource depletion and energy use. Thus, building projects may be made eco-friendlier and more cost-effective. One issue was the lack of reclaimed concrete. Concrete is a seasonal waste product; therefore, it was inconsistently used throughout the research, reducing profitability. Also, the recycling materials vary in size and the locations of ‘urban dumps’ change. Thus, recycling concrete is more challenging than maintaining a reliable cash source. Predictability is owing to a lack of material and price volatility.
As stated before, reducing waste is difficult with many contributing elements. Van Tran interviewed seven experienced construction experts in 2017. These interviews were conducted to understand better the industry’s inadequate waste reduction practices. According to interviewees, the present waste fee of $10 per tonne (2017) is an insufficient incentive for construction enterprises to adopt better waste reduction plans. The existing levy has little impact on a company’s bottom line; therefore, it doesn’t motivate them to change. The levy charge must be hiked to $150 per tonne (Tran, 2017). In the model developed by Yuan et al. (Ding et al., 2015), a considerable rise in waste levies is required to observe meaningful change by contractors. This association is generally accepted as a waste reduction strategy. According to the interviewees, companies that do not decrease their trash should be penalised, not just financially.
Advantages of Recycling Construction Materials
The idea that our natural resources will someday become limited if people continue to mismanage and exploit them drives the usage of recycled materials in the building. Thus, the three pillars of sustainability will benefit the environment, Economy, and society (Khahro et al., 2021). Using recycled materials in the building has several benefits. Increasing the capacity to recycle and reuse building debris reduces the amount dumped in landfills, extending their useful life. Chemical additions in construction materials increase landfill contamination. Toxic contaminants may enter natural rivers and streams through groundwater intrusion. Expanding the use of recycled materials reduces the need to transport garbage from the building site to the landfill, lowering total CO2 emissions. There is a concern that eliminating landfill usage may result in job losses; nevertheless, new jobs can be created utilising recycled materials. This is because recycled materials, unlike reused materials, will be modified to improve the secondary product while keeping their physical attributes to allow the material or product to perform its role in the structure. These procedures need skill sets, thereby creating job opportunities. Providing such changes will help the Economy while also helping to lessen negative environmental repercussions. Population growth will raise the demand for land development. Increased recycling in the building sector reduces land conversion to landfills, making more quality land accessible for home development. Toxic compounds from building materials discarded in landfills wind up in rivers and natural streams. These unmanaged situations may affect the surrounding living species, endangering the community’s health. Due to heavy winds, bad scents from landfills may also be problems for adjacent communities.
Materials that can be Recycled
Concrete is a widely utilised building material that consumes limited resources and produces CO2. Using recycled materials reduces waste streams and production by-products. A 2018 assessment of the literature on these materials yielded encouraging findings (Tavakoli, Hashempour and Heidari, 2018). The research examined waste materials such as Glass, plastic (PET), tile and ceramics, clay bricks, tires and rubber, metal, concrete, agricultural waste, silica fume, fly ash, etc. The research indicated that using trash in concrete, mainly aggregate, may minimise waste transfer to landfills. Using garbage in cement minimises hazardous chemicals in concrete while also recycling. The review’s details are described here. Adding trash as an aggregate to concrete has several advantages. Glass may improve the characteristics of concrete. Glass may be crushed into three distinct forms: CGA, FGA, and Glass Powder (GP). A pozzolanic reaction occurs when Glass is combined with cement, reducing CO2 and NO2 emissions (Ismail and AL-Hashmi, 2008). Glass has a higher thermal conductivity than aggregate; therefore, it may be utilised in structures that need thermal stability (Poutos et al., 2008). Combining coarse and fine Glass improves water absorption and reduces shrinkage.
Plastic used in PET concrete is considered environmentally friendly (Choi et al., 2005). Adding this plastic to concrete may boost its ductility and decrease shrinkage fractures (Singh, Shukla and Brown, 2004). The concrete is very lightweight yet is of good quality. Workability, density, modulus of elasticity, tensile strength, and slump are all reduced with lightweight concrete (Akçaözoğlu, Atiş and Akçaözoğlu, 2010). This aggregate is ideal for light, corrosion-resistant concrete.
Tiles, marble, and ceramic are alternative aggregates that increase concrete characteristics. Using coarse ceramic granules (10–20%) enhances concrete compressive strength, decreasing specific weight without affecting water absorption. However, ceramics are porous and rigid; thus, water absorption and elasticity are weak. Tiles and ceramics are light and pozzolanic. Ceramics have qualities that vary depending on the manufacturing process and other factors. This may impair their performance in concrete; thus, they should be tested beforehand. Fired bricks may be used as sand in concrete. The research indicated that using clay bricks as sand might save money and time. Except for corrosion caused by steel reinforced bars, the concrete had no detrimental consequences. The concrete qualities provided no further advantages (Tavakoli, Hashempour and Heidari, 2018).
Tires and rubber are wastes with little recycling potential. Rubber in concrete solves this issue by lowering the rigidity of concrete and protecting it from fire. This research found an increase in flexural strength compared to the control group. While the brittleness of the control sample resulted in a fracture, the addition of the rubber fibre resulted in deformation but not collapse [59]. Silica flume mixed with cement paste and rubber particles enhanced compressive strength (Yehia and Emam, 2018). This fibre also increased freeze-thaw resistance. Rubber seems an excellent aggregate addition, but further study is needed to understand its strength and durability.
Given that 20–30% of agricultural output is trash, it is critical to maximise recycling. Almond and coconut shells have been employed in a recent agricultural waste concrete study. According to one research, using almond shells as coarse aggregate resulted in a slump similar to standard concrete but with more air content. Another research used coconut shells to make lightweight, high-quality concrete. The lighter coarse-grain aggregate possessed the same mechanical qualities as the heavier coarse-grain aggregate. It had the same quality and flexural characteristics as the standard sample. The compressive strength of coconut shell concrete may be lowered by 22% by reducing the water-cement ratio. Concrete waste research started during WWII, making it the oldest recycled factual material. Adding fly ash to the mix helped reduce shrinkage caused by the substantial waste. Another analysis indicated that using clay brick powder as cement compensated for the waste aggregate’s compressive strength loss. The study shows that concrete debris may be utilised as an aggregate. However, various projects demand different definite qualities, and the quantity of trash can substantially alter the substantial performance.
17% of the material is slag (Tavakoli, Hashempour and Heidari, 2018). This by-product has a high shear modulus and chemical stability in alkaline and acidic conditions. Concrete mixed with slag had better water absorption and tensile and compressive strength. The slump increased with density and bending strength, as anticipated. Studies have demonstrated that ultra-strong concrete may be made at roughly 150 MPa. Steel furnace slag has a substantially greater hardness than typical aggregates, boosting flexural and compressive strength, yet, adding slag to concrete adds weight.
Because of its ‘super pozzolanic’ qualities, silica fume is a by-product of silica metal manufacturing. One research indicated that replacing 10–15% of the cement with silica powder enhanced early drying strength. Alternatively, another research finds silica flume may affect concrete durability. Because silica fume has various detrimental effects, it should only be used as required. Zhang et al. studied the impact resistance, mechanical characteristics, and durability of coal fly ash concrete. The authors observed that adding nano-silica (1–5% of the binder weight) improved the concrete’s mechanical characteristics and freezing-thawing resistance. Including nano-silica, it increased the samples’ compressive, flexural, and splitting tensile strengths by 15%, 27%, and 19%, respectively. Adding nano-silica to basalt fiber-modified recycled aggregate concrete is helpful. Adding basalt fibre may prevent the development and spread of primary microcracks in recycled aggregate concrete and mortar. In this case, nano-silica fills microcracks and promotes cement hydration. Another study found that adding nano-silica to mortar may aid polymerisation; however, exceeding the critical ratio can adversely affect mechanical qualities.
Rice husk has excellent pozzolanic qualities when burnt, making it an ideal waste material for concrete. One research indicated that adding rice husk to high-performance micro silica concrete reduced the cement’s porosity. Compressive strength and water absorption also improved. In addition to compressive strength and other mechanical qualities, resistance to chloride attack was certified. Rice husk may be utilised in high-strength concrete or repair mortars for nations with limited aggregate supply. It is necessary to employ rice husk as a cement addition at an appropriate amount to obtain the required qualities.
Fly ash is a by-product of coal combustion. Using fly ash instead of cement for 40–60% of the cement resulted in a 28-day improvement in compressive strength. Also, pozzolanic fly ash has outstanding mechanical qualities, durability, and low chloride permeability (Uysal and Akyuncu, 2012). According to research, fly ash, unlike concrete debris and brick, does not degrade steel reinforcement. After 90 days, fly ash generates concrete with more muscular compressive strength and water absorption than 10% glass powder. To decrease the harmful Alkali-Silica Reaction (ASR), silica should be added to the concrete as an additive.
Early ceramic tile chemistry analyses revealed pozzolanic characteristics. In one investigation, the utilisation of clay brick waste in cement was 91 per cent stronger than in regular concrete. The replacement cement also lowered concrete permeability and boosted efficiency. Alternatively, tile powder may be combined with silica flume to form concrete with comparable qualities (Tavakoli, Hashempour and Heidari, 2018).
Circular Economy for Construction and Demolition Waste Paradigms and Model Strategies
A literature study indicated that research on circular Economy and building in Australasia, notably New Zealand, is scarce. If Circular Economy is implemented in the building, environmental and economic difficulties may be minimised. A concept for integrating Circular Economy into the construction industry suggested that it may be done in three levels or stages: micro, meso, and macro. The authors believe that the micro set of the Circular Economy should concentrate on eco-friendly design and procedures and the meso level on waste trading networks. For example, a collaborative industry with many stakeholders must cope with the 3R principles [102,103]. Only the UK and the Netherlands have Circular Economies in construction enterprises. For example, the UK has implemented Resource Efficient Construction, which lowers waste while lowering GHG emissions. A questionnaire-based pilot study in Denmark found that the building process may move through the ReSOLVE framework’s share, optimise, and loop phases. In the Netherlands, the International Management Search Association (IMSA) actively incorporates Circular Economy (Yumpu, n.d.). On-going waste, negative impacts on the planet’s ecosystem, illicit dumps of garbage, and lack of assistance from top building groups are all addressed in the proposed framework.
According to Esa et al., the 3Cs (contractor, consultant, and client) should be involved in the 3R operations of construction waste throughout the five phases of the project lifecycle: planning, designing, procurement, construction, and demolition. A micro-level industrialised building system (IBS) was recommended for effective and sustainable facility management. On a micro level, it was proposed that the building sector’s laws be implemented to reduce waste and promote sustainable growth. As total trash elimination is impossible, authorities should control construction and demolition waste via adequate worker supervision. The model suggested by the authors includes this framework and the responsibilities of different stakeholders at various phases of the project lifecycle. The multiple waste reduction solutions listed above align with the 3R operations of practical construction and demolition waste management.
Thoughts about Scientific Reuse
While adopting a circular economy in the construction and demolition industry has many advantages, the scientific usage of such wastes must be researched. Contractors should be encouraged to recycle and reuse construction and demolition waste materials, provided the recovery procedure results in a product of an acceptable grade as specified by specifications and is economically viable. Recycled waste materials’ chemistry, physical, mechanical, and durability properties must be studied. The environmental aspects of recycled materials include their sustainability and life cycle. Recycling is energy-intensive, but the benefits to society and the environment exceed the costs, making recycling economically viable. For example, energy is already spent on mining, quarrying, and transportation in construction and demolition waste recovery. This may also minimise emissions and other environmental problems, such as the loss of natural resources and the spread of dust and airborne particles. However, life cycle analysis may be used to measure the contribution of the Circular Economy to sustainability. Also, considering both hazardous and non-toxic environmental consequences, Butera et al. The scientists found that transportation contributes the greatest (60–95%) to non-toxic products. Surprisingly, dumping minerals has less effect than using them. This is due to less leachate per tonne of construction and demolition waste reaching groundwater resources over 100 years. A significant feature of leaching oxyanions was identified to be soil Cr immobilisation. Overall, leaching emissions influenced toxicity consequences more than manufacturing the same materials. The life cycle study indicated that transportation (on-site and off-site) absorbed 15% of CO2.
Conclusion
Annually, a considerable part of construction and demolition trash is in landfills, causing severe environmental and socioeconomic issues. The volume of construction and demolition waste dumped is increasing alarmingly, with detrimental repercussions. A few model practices exist to recover or reuse a tiny fraction of construction and demolition waste; nevertheless, worldwide adoption faces several challenges/barriers. The research shows that the problems fall into five categories: legal, technological, social, behavioural, and economic. Within the core areas, difficulties include legislation and regulations, permits and requirements, technology limitations, quality and performance, knowledge and information, and the expenses involved with early Circular Economy model adoption. The magnitude of problems also varies based on the project size and country. Thus, a basic framework and a practical method are required to shift from a linear to a circular economy in CDM. We must first investigate and categorise the financial and societal advantages of recycling construction and demolition trash and the significant hurdles. Various integrative models and frameworks from the UK, Netherlands, Malaysia, Denmark, etc., were evaluated and debated. The feasibility and advantages of recycling building waste materials are examined in this review study. Previously published data on ecological, economic, strength, and durability were revealed. It was discovered that recycling waste materials in the building positively affects the environment, Economy, and durability. Environmentally-friendly construction will also assist the government and stakeholders in achieving sustainability objectives. The resources necessary to develop and execute waste management strategies may also be reduced; nevertheless, the construction industry faces various obstacles that prohibit the recycling of construction and demolition waste materials in building operations. Quality assurance systems, market uncertainty regarding waste materials availability and perceptions, and high costs of material recovery technologies were cited as barriers.
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How civil engineering should embed principles, embrace sustainability, and implement circular economy?
In recent decades, global urbanisation has accelerated human population expansion, requiring more material resources. Construction uses 32% of natural resources (Yeheyis et al., 2012). However, this figure is lower than in the 1990s (40%) (Rees, 2010); it is estimated that over 75% of building waste has a residual value and is not presently utilised or recycled. Insufficiently integrated waste management framework (Yeheyis et al., 2012).
In general, construction and demolition wastes are nothing that is no longer usable due to building, restoration, or destruction. Most of the time, such garbage is dumped. Construction and demolition trash represents 30% of worldwide waste production (Papargyropoulou et al., 2011), with about 35% of construction and demolition waste deposited in landfills yearly (Menegaki and Damigos, 2018). The construction sector has a substantial environmental effect due to natural resources, energy consumption, and trash creation.
This is because the linear economic paradigm depends on taking, manufacturing, and discarding. Using energy-intensive equipment, raw materials are taken from natural resources and processed into building materials. Because most building materials cannot be deconstructed, they are thrown into a landfill or burnt (Mangialardo and Micelli, 2018). The negative repercussions of construction and demolition waste handling include environmental damage and public health (Lu and Yuan, 2012). This scenario necessitates an efficient framework to minimise pollution, climate change, and resource depletion (Yeheyis et al., 2012),7]. Concrete, wood, bricks, Glass, steel, and other rejected materials are often found in construction and demolition trash (Solís-Guzmán et al., 2009). Due to the vast construction and demolition waste generated each year, trash must be handled sustainably. Traditional environmental mitigation measures, such as linear Economy, have been inefficient. For sustainable development, the term Circular Economy has arisen as a unique method to decrease negative environmental impacts while increasing economic growth. The Circular Economy is a unique reformative framework that helps optimise raw material use and guarantees material value throughout its lifespan (Bilal et al., 2020). Circular Economy also reduces trash output and conserves natural resources. This technique shows that everything created can be recycled, reconditioned, or utilised. In their conclusion, Hossain et al. (Hossain et al., 2020) stated that employing Circular Economy for construction and demolition waste would improve sustainable resources, promote material efficiency by recycling/reusing construction waste, and reduce wasteful waste generation and disposal. Generally, the Circular Economy tries to repurpose materials that would otherwise be dumped into landfills in the construction business.
Different dimensions must be well understood to properly apply Circular Economy in a construction business. Ghisellini et al. studied the costs and advantages of the Circular Economy in the building and demolition industry. Lederer et al. used a material flow analysis to establish how a Circular Economy may reduce raw mineral imports for the building industry in Vienna. They discovered that reusing/recycling building minerals might cut imports by 32%. Although various efforts have been made to recycle or recover construction and demolition waste, little research has been done on the viability of including a Circular Economy in the current built environment. Unlike small and medium-sized building projects, large-scale CE applications pose significant obstacles. Combining novel technologies, such as BIM (Building Information Modelling), with Circular Economy might alleviate the issues in large-scale built environments. Several techniques have been suggested to help the building industry migrate to Circular Economy. Employing sustainable and durable materials, designing for disassembly, using modular and prefabricated pieces, and developing recovery methods [10,16]. However, little study has been done so far on the above methodologies.
This assessment will present a distinct viewpoint on how construction and demolition waste may be repurposed by adopting a Circular Economy strategy. Unlike the linear Economy, recovering or reusing resources requires additional stages, which means more obstacles. This research will explore the problems and limitations of implementing a Circular Economy for construction and demolition waste from a fresh perspective while minimising environmental consequences and reducing carbon emissions. The prospective usage of several materials that have proved helpful in building (especially concrete) will next be discussed. Also, this research provides a theoretical framework to encourage better use of recycled materials in the establishment or for other services.
Materials and Methods
This study’s approach has two primary stages. A systematic review was done to identify and synthesise scientific evidence in the first step. This method collects all essential research evidence. The most extensive scientific database, Science Direct, gathered relevant material for the systematic review. Keywords included “construction and demolition”, “waste”, “construction”, “circular economy”, “framework”, “climate change”, “carbon emissions”, etc. The Boolean operators (AND) and (OR) were employed to retrieve relevant articles. A few examples include “circular economy” AND “framework,” “construction and demolition waste” AND “waste,” “construction and demolition” AND “strategies,” and so on. The search was restricted to 2005–2021, with most articles from the past five years. This aimed to guarantee the retrieval of unique ideas and research concepts that were relevant and original. The benefit of this work above prior publications is that it discusses the relevance of environmental repercussions based on construction and demolition waste.
English is a worldwide lingua franca and is commonly used for communication. Similarly, most of the sources included in this study were peer-reviewed studies in reputable, well-indexed journals. Some of the references came from citations in the literature. With this framework, early adoption of this successful strategy may be achieved.
Background Information
Waste
Garbage is an unavoidable by-product of production and usage, whether an industrial by-product or demolition waste. However, owing to pollution, resource depletion, landfill site shortages, and climate change, academics have started investigating society’s role in waste reduction [17,18].
Seadon argues that society’s ‘mine-build-discard’ mentality is unsustainable. According to the essay, unsustainable civilisations inevitably collapse. Thriving communities recognise the value of limited resources, utilise them responsibly, and appreciate the surrounding environment. It is dynamic in all aspects, notably productivity, and uses scarce resources responsibly and effectively.
Globally, the quantity of garbage created each year is frightening. The global production of municipal solid waste was 2.02 billion metric tonnes in 2016 and is expected to rise to 3.4 billion metric tonnes by 2050 (Tiseo, 2021). A 70% rise in worldwide garbage output is estimated if the existing system is maintained. To solve this situation, the world community must work together to safeguard the future prosperity of our children.
The New Zealand construction sector was expected to rise 70% by 2029 before the COVID-19 pandemic. This means more horizontal infrastructure projects for New Zealanders, which means more jobs (Harman, n.d.). As a result, building and demolition trash, which accounts for around half of New Zealand’s landfill garbage, is expected to rise, possibly straining the country’s waste management system. Recycling waste materials is one technique New Zealand’s construction sector may use to decrease its environmental impact. Concrete is one material that has been shown to benefit from trash. According to Tavakoli et al. (Tavakoli, Hashempour and Heidari, 2018), concrete is the most significant building material nowadays. He also claims that employing waste materials in concrete may considerably lessen the negative environmental consequences of concrete.
Concepts and Foundations of Circular Economy
Developing urban infrastructure has made sustainability a popular term and a worry (Anastasiades et al., 2020). As a result, pollution and environmental damage increase (Jhatial et al., 2020). Sustainability is vital in every construction project since it helps the project and the environment. Thus, a popular definition of sustainable development is the certainty that a project meets current requirements without jeopardising future demands (Anastasiades et al., 2020). Sustainability has three pillars: planet, people, and profit. The planet’s ecosystem and environmental conditions are vital, but people’s demands should be met to maximise profit within limited resources. Sustainable development seeks to make growth socially, ecologically, and economically feasible, tolerable, and equitable.
The concept of Circular Economy arose from the desire to raise awareness about the environmental damage caused by using and wasting raw resources. The Circular Economy is being investigated as a potential solution for natural resource depletion. The Circular Economy idea grew out of the 3Rs (Reduce-Reuse-Recycle). The 4R framework focuses on reducing, reusing, recycling, and recovering raw materials (Anastasiades et al., 2020). Unlike in the linear Economy, natural materials in the Circular Economy are mended, recycled, and refurbished to be used in other processes. Thus, a Circular Economy’s principles include not buying surplus raw materials, changing design standards, and minimising, reusing, and recycling trash. Such approaches effectively recycle, decrease waste, and prevent global environmental damage.
Construction Waste
Construction waste is categorised based on its origin or type. The writers defined trash as physical (residual debris) and non-physical (waste) (time overruns and cost overruns). Figure 2 investigates building waste sources. As indicated in Figure 2, building debris may be classified as either artificial or natural. Artificial sources include design, procurement, material handling, operation, residue, and other sources (ElHaggar, 2007). construction and demolition waste materials are valuable and might be repurposed for concrete buildings. In concrete, the majority may be recycled as coarse or fine aggregate (Ulsen et al., 2013). Metals (6%), organic garbage (2%), Glass and hazardous materials (2%), and miscellaneous (5%) (Ghorbanian et al., 2017).
Figure 3 shows the tonnes of building trash generated in major European nations and New Zealand. Construction trash is a significant contributor in Denmark, France, Ireland, and Germany. Poland, Lithuania, Bulgaria, Greece, Slovakia, Hungary, and New Zealand generated the most minor building trash (Forbes, 2018). Construction and demolition waste accounts for over half of New Zealand’s yearly trash; hence, waste reduction efforts must be heavily engaged (Ghorbanian et al., 2017). However, 2019 Auckland City Council research on the diversion of demolition trash indicated that recycling would still have substantial advantages (Rohani et al., 2019). The research focused on the cost-benefit analysis of reusing demolition trash for new dwellings. Opt A, a moderate deconstruction technique that emphasises partial trash recovery and recycling, or Opt B, an intense deconstruction approach that emphasises the two highest levels of the hierarchy. While the developers would only break even, the net benefits to society were significant for both choices (A: NPV = $6.97 m, B: NPV = $14.46 m). Employers earned skills and experience through on-the-job training, while employees got skills and expertise by reusing building materials. While reducing and reusing were proven to be better for society, recycling was also helpful. For many materials, recycling is the sole option. Hence it is an integral waste reduction approach worth exploring.
Waste Minimisation in the Circular Economy
The core of the Circular Economy is reducing waste in landfills by reusing rejected materials in various ways. It is a 4R approach concentrating on Reduce-Reuse-Recycle-Recover raw material operations (Anastasiades et al., 2020). Less acquisition of raw materials means less GHG emissions, which helps the Economy and the environment. Moreover, reducing trash creation lowers the harmful consequences of garbage generation on our living environment.
Several studies have examined the economic viability of decreasing trash. This effort focuses on reducing construction and demolition waste, the leading contributor to landfills worldwide (Osmani and Villoria-Sáez, 2019). A cost-benefit analysis conducted in Malaysia in 2006 revealed reducing construction and demolition waste is possible with a 2.5% net profit (Begum et al., 2006). This research examined the costs and advantages of reducing trash on a Malaysian construction site. The study showed several immediate benefits, including reduced purchase costs from reusing and recycling goods, reduced garbage collection and transport costs, and reduced disposal charges. Intangible advantages include decreased responsibility for environmental issues or worker safety, loosened soil and groundwater pollution risk, and better public perception of the ecological problems—direct expenditures for collection and separation, equipment purchases, storage, and transportation. Intangible expenses included worker health risks and negative externalities like noise and odour. According to Auckland City Council research, less waste is economically viable and has many unquantifiable advantages. According to both studies, the rise in wastage levies might push construction businesses to adopt better waste reduction measures.
An independent researcher did a cost-benefit study to evaluate the waste reduction hypothesis (Ghorbanian et al., 2017). The project included building a complicated model of a waste chain that appropriately represented society’s trash. This conceptual model stresses the complexity of waste reduction and explains prior global waste reduction challenges. According to the model, a high waste tax would increase net benefits for construction businesses and society, but it would also encourage the general people to dump their garbage unlawfully. It was decided that stiffer punishments should be implemented to counteract this issue. It was discovered that under the four billing systems, the expenses initially surpassed the benefits, but by the 11th month, the benefits started to outweigh the costs. The high-charge schemes also encouraged contractors to start trash management early, making it more effective. The net advantages of reduced charge schemes increased considerably when the regulation was tightened. To be effective, trash charges must be more than 76 yuan/ton (NZD 15.50).
Waste reduction for contractors has been economically beneficial, as has waste minimisation for recycling organisations. One research looked at the economics of recycled concrete aggregate (Tam, 2008). The cost-benefit study included both existing and concrete recycling methods for waste disposal. Using concrete debris as aggregates instead of dumping it in landfills may assist the building sector (Tam, 2008). The research indicated a $30,916,000 annual net gain and reduced resource depletion and energy use. Thus, building projects may be made eco-friendlier and more cost-effective. One issue was the lack of reclaimed concrete. Concrete is a seasonal waste product; therefore, it was inconsistently used throughout the research, reducing profitability. Also, the recycling materials vary in size and the locations of ‘urban dumps’ change. Thus, recycling concrete is more challenging than maintaining a reliable cash source. Predictability is owing to a lack of material and price volatility.
As stated before, reducing waste is difficult with many contributing elements. Van Tran interviewed seven experienced construction experts in 2017. These interviews were conducted to understand better the industry’s inadequate waste reduction practices. According to interviewees, the present waste fee of $10 per tonne (2017) is an insufficient incentive for construction enterprises to adopt better waste reduction plans. The existing levy has little impact on a company’s bottom line; therefore, it doesn’t motivate them to change. The levy charge must be hiked to $150 per tonne (Tran, 2017). In the model developed by Yuan et al. (Ding et al., 2015), a considerable rise in waste levies is required to observe meaningful change by contractors. This association is generally accepted as a waste reduction strategy. According to the interviewees, companies that do not decrease their trash should be penalised, not just financially.
Advantages of Recycling Construction Materials
The idea that our natural resources will someday become limited if people continue to mismanage and exploit them drives the usage of recycled materials in the building. Thus, the three pillars of sustainability will benefit the environment, Economy, and society (Khahro et al., 2021). Using recycled materials in the building has several benefits. Increasing the capacity to recycle and reuse building debris reduces the amount dumped in landfills, extending their useful life. Chemical additions in construction materials increase landfill contamination. Toxic contaminants may enter natural rivers and streams through groundwater intrusion. Expanding the use of recycled materials reduces the need to transport garbage from the building site to the landfill, lowering total CO2 emissions. There is a concern that eliminating landfill usage may result in job losses; nevertheless, new jobs can be created utilising recycled materials. This is because recycled materials, unlike reused materials, will be modified to improve the secondary product while keeping their physical attributes to allow the material or product to perform its role in the structure. These procedures need skill sets, thereby creating job opportunities. Providing such changes will help the Economy while also helping to lessen negative environmental repercussions. Population growth will raise the demand for land development. Increased recycling in the building sector reduces land conversion to landfills, making more quality land accessible for home development. Toxic compounds from building materials discarded in landfills wind up in rivers and natural streams. These unmanaged situations may affect the surrounding living species, endangering the community’s health. Due to heavy winds, bad scents from landfills may also be problems for adjacent communities.
Materials that can be Recycled
Concrete is a widely utilised building material that consumes limited resources and produces CO2. Using recycled materials reduces waste streams and production by-products. A 2018 assessment of the literature on these materials yielded encouraging findings (Tavakoli, Hashempour and Heidari, 2018). The research examined waste materials such as Glass, plastic (PET), tile and ceramics, clay bricks, tires and rubber, metal, concrete, agricultural waste, silica fume, fly ash, etc. The research indicated that using trash in concrete, mainly aggregate, may minimise waste transfer to landfills. Using garbage in cement minimises hazardous chemicals in concrete while also recycling. The review’s details are described here. Adding trash as an aggregate to concrete has several advantages. Glass may improve the characteristics of concrete. Glass may be crushed into three distinct forms: CGA, FGA, and Glass Powder (GP). A pozzolanic reaction occurs when Glass is combined with cement, reducing CO2 and NO2 emissions (Ismail and AL-Hashmi, 2008). Glass has a higher thermal conductivity than aggregate; therefore, it may be utilised in structures that need thermal stability (Poutos et al., 2008). Combining coarse and fine Glass improves water absorption and reduces shrinkage.
Plastic used in PET concrete is considered environmentally friendly (Choi et al., 2005). Adding this plastic to concrete may boost its ductility and decrease shrinkage fractures (Singh, Shukla and Brown, 2004). The concrete is very lightweight yet is of good quality. Workability, density, modulus of elasticity, tensile strength, and slump are all reduced with lightweight concrete (Akçaözoğlu, Atiş and Akçaözoğlu, 2010). This aggregate is ideal for light, corrosion-resistant concrete.
Tiles, marble, and ceramic are alternative aggregates that increase concrete characteristics. Using coarse ceramic granules (10–20%) enhances concrete compressive strength, decreasing specific weight without affecting water absorption. However, ceramics are porous and rigid; thus, water absorption and elasticity are weak. Tiles and ceramics are light and pozzolanic. Ceramics have qualities that vary depending on the manufacturing process and other factors. This may impair their performance in concrete; thus, they should be tested beforehand. Fired bricks may be used as sand in concrete. The research indicated that using clay bricks as sand might save money and time. Except for corrosion caused by steel reinforced bars, the concrete had no detrimental consequences. The concrete qualities provided no further advantages (Tavakoli, Hashempour and Heidari, 2018).
Tires and rubber are wastes with little recycling potential. Rubber in concrete solves this issue by lowering the rigidity of concrete and protecting it from fire. This research found an increase in flexural strength compared to the control group. While the brittleness of the control sample resulted in a fracture, the addition of the rubber fibre resulted in deformation but not collapse [59]. Silica flume mixed with cement paste and rubber particles enhanced compressive strength (Yehia and Emam, 2018). This fibre also increased freeze-thaw resistance. Rubber seems an excellent aggregate addition, but further study is needed to understand its strength and durability.
Given that 20–30% of agricultural output is trash, it is critical to maximise recycling. Almond and coconut shells have been employed in a recent agricultural waste concrete study. According to one research, using almond shells as coarse aggregate resulted in a slump similar to standard concrete but with more air content. Another research used coconut shells to make lightweight, high-quality concrete. The lighter coarse-grain aggregate possessed the same mechanical qualities as the heavier coarse-grain aggregate. It had the same quality and flexural characteristics as the standard sample. The compressive strength of coconut shell concrete may be lowered by 22% by reducing the water-cement ratio. Concrete waste research started during WWII, making it the oldest recycled factual material. Adding fly ash to the mix helped reduce shrinkage caused by the substantial waste. Another analysis indicated that using clay brick powder as cement compensated for the waste aggregate’s compressive strength loss. The study shows that concrete debris may be utilised as an aggregate. However, various projects demand different definite qualities, and the quantity of trash can substantially alter the substantial performance.
17% of the material is slag (Tavakoli, Hashempour and Heidari, 2018). This by-product has a high shear modulus and chemical stability in alkaline and acidic conditions. Concrete mixed with slag had better water absorption and tensile and compressive strength. The slump increased with density and bending strength, as anticipated. Studies have demonstrated that ultra-strong concrete may be made at roughly 150 MPa. Steel furnace slag has a substantially greater hardness than typical aggregates, boosting flexural and compressive strength, yet, adding slag to concrete adds weight.
Because of its ‘super pozzolanic’ qualities, silica fume is a by-product of silica metal manufacturing. One research indicated that replacing 10–15% of the cement with silica powder enhanced early drying strength. Alternatively, another research finds silica flume may affect concrete durability. Because silica fume has various detrimental effects, it should only be used as required. Zhang et al. studied the impact resistance, mechanical characteristics, and durability of coal fly ash concrete. The authors observed that adding nano-silica (1–5% of the binder weight) improved the concrete’s mechanical characteristics and freezing-thawing resistance. Including nano-silica, it increased the samples’ compressive, flexural, and splitting tensile strengths by 15%, 27%, and 19%, respectively. Adding nano-silica to basalt fiber-modified recycled aggregate concrete is helpful. Adding basalt fibre may prevent the development and spread of primary microcracks in recycled aggregate concrete and mortar. In this case, nano-silica fills microcracks and promotes cement hydration. Another study found that adding nano-silica to mortar may aid polymerisation; however, exceeding the critical ratio can adversely affect mechanical qualities.
Rice husk has excellent pozzolanic qualities when burnt, making it an ideal waste material for concrete. One research indicated that adding rice husk to high-performance micro silica concrete reduced the cement’s porosity. Compressive strength and water absorption also improved. In addition to compressive strength and other mechanical qualities, resistance to chloride attack was certified. Rice husk may be utilised in high-strength concrete or repair mortars for nations with limited aggregate supply. It is necessary to employ rice husk as a cement addition at an appropriate amount to obtain the required qualities.
Fly ash is a by-product of coal combustion. Using fly ash instead of cement for 40–60% of the cement resulted in a 28-day improvement in compressive strength. Also, pozzolanic fly ash has outstanding mechanical qualities, durability, and low chloride permeability (Uysal and Akyuncu, 2012). According to research, fly ash, unlike concrete debris and brick, does not degrade steel reinforcement. After 90 days, fly ash generates concrete with more muscular compressive strength and water absorption than 10% glass powder. To decrease the harmful Alkali-Silica Reaction (ASR), silica should be added to the concrete as an additive.
Early ceramic tile chemistry analyses revealed pozzolanic characteristics. In one investigation, the utilisation of clay brick waste in cement was 91 per cent stronger than in regular concrete. The replacement cement also lowered concrete permeability and boosted efficiency. Alternatively, tile powder may be combined with silica flume to form concrete with comparable qualities (Tavakoli, Hashempour and Heidari, 2018).
Circular Economy for Construction and Demolition Waste Paradigms and Model Strategies
A literature study indicated that research on circular Economy and building in Australasia, notably New Zealand, is scarce. If Circular Economy is implemented in the building, environmental and economic difficulties may be minimised. A concept for integrating Circular Economy into the construction industry suggested that it may be done in three levels or stages: micro, meso, and macro. The authors believe that the micro set of the Circular Economy should concentrate on eco-friendly design and procedures and the meso level on waste trading networks. For example, a collaborative industry with many stakeholders must cope with the 3R principles [102,103]. Only the UK and the Netherlands have Circular Economies in construction enterprises. For example, the UK has implemented Resource Efficient Construction, which lowers waste while lowering GHG emissions. A questionnaire-based pilot study in Denmark found that the building process may move through the ReSOLVE framework’s share, optimise, and loop phases. In the Netherlands, the International Management Search Association (IMSA) actively incorporates Circular Economy (Yumpu, n.d.). On-going waste, negative impacts on the planet’s ecosystem, illicit dumps of garbage, and lack of assistance from top building groups are all addressed in the proposed framework.
According to Esa et al., the 3Cs (contractor, consultant, and client) should be involved in the 3R operations of construction waste throughout the five phases of the project lifecycle: planning, designing, procurement, construction, and demolition. A micro-level industrialised building system (IBS) was recommended for effective and sustainable facility management. On a micro level, it was proposed that the building sector’s laws be implemented to reduce waste and promote sustainable growth. As total trash elimination is impossible, authorities should control construction and demolition waste via adequate worker supervision. The model suggested by the authors includes this framework and the responsibilities of different stakeholders at various phases of the project lifecycle. The multiple waste reduction solutions listed above align with the 3R operations of practical construction and demolition waste management.
Thoughts about Scientific Reuse
While adopting a circular economy in the construction and demolition industry has many advantages, the scientific usage of such wastes must be researched. Contractors should be encouraged to recycle and reuse construction and demolition waste materials, provided the recovery procedure results in a product of an acceptable grade as specified by specifications and is economically viable. Recycled waste materials’ chemistry, physical, mechanical, and durability properties must be studied. The environmental aspects of recycled materials include their sustainability and life cycle. Recycling is energy-intensive, but the benefits to society and the environment exceed the costs, making recycling economically viable. For example, energy is already spent on mining, quarrying, and transportation in construction and demolition waste recovery. This may also minimise emissions and other environmental problems, such as the loss of natural resources and the spread of dust and airborne particles. However, life cycle analysis may be used to measure the contribution of the Circular Economy to sustainability. Also, considering both hazardous and non-toxic environmental consequences, Butera et al. The scientists found that transportation contributes the greatest (60–95%) to non-toxic products. Surprisingly, dumping minerals has less effect than using them. This is due to less leachate per tonne of construction and demolition waste reaching groundwater resources over 100 years. A significant feature of leaching oxyanions was identified to be soil Cr immobilisation. Overall, leaching emissions influenced toxicity consequences more than manufacturing the same materials. The life cycle study indicated that transportation (on-site and off-site) absorbed 15% of CO2.
Conclusion
Annually, a considerable part of construction and demolition trash is in landfills, causing severe environmental and socioeconomic issues. The volume of construction and demolition waste dumped is increasing alarmingly, with detrimental repercussions. A few model practices exist to recover or reuse a tiny fraction of construction and demolition waste; nevertheless, worldwide adoption faces several challenges/barriers. The research shows that the problems fall into five categories: legal, technological, social, behavioural, and economic. Within the core areas, difficulties include legislation and regulations, permits and requirements, technology limitations, quality and performance, knowledge and information, and the expenses involved with early Circular Economy model adoption. The magnitude of problems also varies based on the project size and country. Thus, a basic framework and a practical method are required to shift from a linear to a circular economy in CDM. We must first investigate and categorise the financial and societal advantages of recycling construction and demolition trash and the significant hurdles. Various integrative models and frameworks from the UK, Netherlands, Malaysia, Denmark, etc., were evaluated and debated. The feasibility and advantages of recycling building waste materials are examined in this review study. Previously published data on ecological, economic, strength, and durability were revealed. It was discovered that recycling waste materials in the building positively affects the environment, Economy, and durability. Environmentally-friendly construction will also assist the government and stakeholders in achieving sustainability objectives. The resources necessary to develop and execute waste management strategies may also be reduced; nevertheless, the construction industry faces various obstacles that prohibit the recycling of construction and demolition waste materials in building operations. Quality assurance systems, market uncertainty regarding waste materials availability and perceptions, and high costs of material recovery technologies were cited as barriers.
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