Significant research initiatives are currently under way to determine how technical characteristics, such as moisture content, the California Bearing Ratio (CBR), and degree of compaction, is affected when recycledconstruction and demolitionwaste (CDW) aggregate is included in pavement layers. Due to high water absorption of recycled aggregates, it is sometimes suggested to use pre-soaked aggregates for construction of road layers using recycled aggregate. Furthermore, designers lack the knowledge of what actually can be recycled in the region. The aim of our project is to verify the technical viability of using constructionwaste and plastic waste (<30µ) as material for the base of road surfaces.
The collected construction and demolitionwaste were crushed, sieved and according to gradation it was separated with a required quantity for the analysis. Natural aggregates according to gradation with the percentages of 4%, 4.5%, 5%, 5.5%, 6% of 60/70 penetration grade bitumen was used, and casted moulds. The mixture having 100% natural aggregates is labeled as control mix. By the results we found the optimum percentage of bitumen. By keeping that as ideal then the partial replacement of natural aggregates by recycledconstructiondemolitionwaste according to gradation was done with optimum bitumen content , 5%, 10%, 15%, 20% & 25% of CDW. From the results found the optimum percentage of CDW, keeping that as constant instead of natural bitumen recycled bitumen was incorporated.
Opportunities for recycledconstruction and demolition product are likely to grow as environmental consciousness grows to meet the increased demand for building material in the future. This helps to encourage digital platform to exchange waste among public and various stakeholder. Innovative and recycled material from construction and demolition wastes will help to tackle the challenges due to abundant waste generation and lack of disposal alternatives. It is therefore important to implement construction and demolitionwaste management planning to achieve the envisaged target to reduce the environmental impact of construction and demolitionwaste. The effort of recycling construction and demolitionwaste helps to achieve eco- friendly, cost-effective construction and sustainable future.
to the rapid rise in urbanization, construction activities are more to meet modern society needs, as a result, production of waste from construction 60% waste is generated from Hongkong, 57% in Australia, 30% in the USA, 30% in European countries . Majority of these wastes ends up in landfills. In many countries space is a constrain and dumping is not possible, which make them recycle or reuse of these wastes. Many researchers suggested that CDW in a coarse fraction is used in pavements and a replacement in concrete. But fine fractions were still not used as efficiently in civil engineering construction . This fine fractions from CDW were arises as a residue of coarse fraction production as high- grade recycledconstruction material for pavements. Mainly these fine fractions consist of natural grains which are crushed from concrete, brick powder, cement powder and motor. Being a pozzolanic and non-cohesive fine fraction one better technique for reuse is by using in geotechnical works for stabilization of fine and soft-grained soils.
Recycled coarse buildings, bridges, concrete pavements etc. aggregates are obtained by crushing of Concrete paving block is versatile, concrete waste from demolition of structural aesthetically attractive, functional and cost components in many structures such as old effective and requires little or no maintenance if correctly manufactured and laid. Paver block are solid, unreinforced precast cement concrete paving units used in the surface course of pavements.(6) Interlocking concrete paving block technology has been introduced in India in construction, a decade ago, for specific requirement like footpaths, parking areas, gardens, etc. We all know that the basic requirement of paver blocks is high compressive strength and low water absorption, so in order to achieve the same conventional results we have replaced the course aggregate and fine aggregate partially (50%) in top and bottom layer because of environmental considerations and growing trend in reusing waste products.
The demand for new construction is ever-increasing with the rise in population. The use of demolition concrete waste as aggregates in concrete is prevailing from over a few years. But due to the concern over its strength from structural point of view it is not largely accepted as a structural material hence being used for insignificant works. Frondistou-Y.  evaluated and compared the mechanical properties of conventional concrete and RAC and concluded that the RAC has a compressive strength of at least 76% and modulus of elasticity from 60% to 100% of the control mix. Test results by Tavakoli et al.  indicated that the strength of recycled aggregate concrete is affected by the strength of original concrete, percentage of coarse aggregate in original concrete and the ratio of top size of aggregate in original concrete to that of recycled aggregate. In this study instead of full replacement of natural aggregates, a part replacement that offers a better structural property in comparison with the conventional concrete is ascertained. Mainly four percentage replacements were selected i.e. 0% (NAC), 20% (RAC 20), 30% (RAC 30) and 40% (RAC 40) to conduct the various tests on its property.
A. ConstructionWaste Scenario Around the World According to Mazumdar (2009), In Scotland 63% of waste was reused in 2000; the remaining 37% waste was dumped in land. The government is developed waste management regulations with code specifications. There are number of trials to establish connections with the planning system, computerization of transfer note scheme to promote numerical analysis and to encourage dialogue between organizations for advisors and contractors to adopt secondary aggregates. According to Danish Environment Protection Agency (DEPA) the constructionwaste produced in 2003 is about 30% of total waste. In constructionwaste 70-75% was generated due to demolition of buildings, 20- 25% was generated due to refurbishment of buildings and the remaining 5 % waste generated from fresh buildings. Recycling is the main problem for Denmark due to landfill site limitations. There have been statutory orders, action plans and voluntary agreements, e.g. asphalt reuse (1985), building waste sorting (1995), etc. Mazumdar (2009) reported that around 40 million constructionwaste is produced. Out of this 80% waste is concrete and brick. The number of measures adopted since 1993, such as waste prevention, stimulation of recycling, promotion of long- lived building materials, products that can be readily disassembled, separation at source and prohibition of building waste at landfill sites. The factors that led to elevated levels of recycling are 1. Source 2 separation. Good recycled product market 3. Prohibition of landfill 4. Guidelines for the use of building waste instead of new aggregates
Since higher amount of building and infrastructure has been constructed in Bangkok, Thailand, the number of construction and demolition (C&D) waste is increasing continuously . The C&D wastes, comprising of concrete, brick, metal, ceramics, roofing, gypsum, and wood, can be classified into two categories: recyclable (70%) and non-recyclable (30%) wastes . It is, however, found that not all the recyclable wastes are yet recycled, and are dumped into landfills. The improvement of C&D waste management, thus, helps reducing the amount of C&D wastes and landfill requirement .
Approximately 94% of roads in the United States are paved with hot mix asphalt (HMA) (NAPA 2002). The structural portion of asphalt pavement can last for decades, but surface layers need periodic maintenance to remain drivable. Maintenance activities on highways and parking lots lead to the generation of waste asphalt pavement when material is milled off of the surface layer. In 1992, 100 million tons of waste HMA were generated in the US, 78 million tons (78%) of which were recycled as aggregate or new HMA (USDOT 1993). State and federal contracts generally stipulate that contractors recycle the HMA removed from the road surface. The contractors then use the recycled asphalt pavement (RAP) in their mixing plants, or as base material for new roads. The RAP is valuable to contractors because it allows them to purchase less binder and aggregate.
One Styrofoam is usually used in packaging purposes for electrical appliances and consist a huge part of solid waste as well because of its extensive use in disposable items like plates and cups, moreover because of its su- perior insulating properties, expanded polystyrene foam, often referred to as Styrofoam is used as building insu- lation material in walls, floors and roofs in residential and commercial buildings. As is the case with all organic compounds, polystyrene burns to give carbon dioxide and water vapor. It is a light weight component however is quit bulky to transport. Styrofoam is a petroleum-based plastic which does not biodegrade by time and is very dangerous when burnt so it presents a real problem. Some researches are conducted to accommodate the Styro- foam in its present form in other materials manufacturing. Jong-Jin Kim, tried in 1998 to form a new type of drainage system which replaces gravel, with pieces of polystyrene, which would otherwise be dumped into land- fills. This new type of product can be used in foundations works, in drainage fields and parking lots . This new product might not be very cost effective in its use when compared to gravel which has very low cost, for that reason continuing research is needed to come up with alternative uses or recycling techniques for used po- lystyrene. Polystyrene is rarely recycled because it is usually not cost effective as the start-up costs for a polys- tyrene recycling plant are enormous and the pay-off, is still uncertain. Moreover Polystyrene is bulky, it's diffi- cult and expensive to transport and cannot even be used for products that contact food because of health con- cerns.
Abstract: Increased construction activities in Australia have led to the generation of a massive volume of construction and demolition (C&D) waste annually. Management of this volume of waste requires an effective waste framework. The literature reported that the current Australian waste framework does not meet expectations and needs immediate improvements. This study was therefore conducted to seek the key C&D stakeholders' opinion about various issues identified in this waste stream. The specific objectives of this study are identification of the main barriers to effective C&D waste management, the impact of current regulations and opportunities to enhance the current C&D waste management system. A survey was conducted in 2019 to capture the stakeholders' perception. 132 participants from various industries and government agencies based in various Australian jurisdictions took part in the survey. The key results showed that the main barriers towards an effective management system are "overregulation, tough acceptance criteria, and increased testing requirements", "lack of local market" and "culture, poor education and low acceptance". Furthermore, a low number of participants indicated that the current legislation encourages waste recovery activities. The main areas of improvements included "providing a guideline that determines the accepted level of contamination for reusing C&D waste”, "preparation of guidelines on requirements of using recycled C&D materials in different industries" and "setting target for reduction, reusing, and recycling C&D waste". The results can inform policy development and be used as evidence for a broader discussion to solve lasting issues in C&D waste management.
ABSTRACT: Construction and demolitionwaste, C&D, is one of the largely produced wastes in Kingdom of Saudi Arabia, KSA. Management of C&D waste is essential in formation, growth and renovation of urban areas. Current municipality legislation and directive sets out to implement C&D waste prevention and recycling measures. Main objective of this study is to determine indicators to estimate amount of C&D waste generated on site and to find best way of recycling waste into a useful product. Part of study in metropolitan area of Dammam, Khobar and Dhahran focuses on generation and management of C&D waste based on construction activity and waste load movements. Data needed to develop indicators is collected through survey studies by suitably designed questionnaires, site investigations and field visits for a reasonable sample of home owners, construction firms and municipality. Laboratory activities were conducted to create a recycled concrete and compare its mechanical properties to a normal mix. Questionnaires results show that largest amount of municipality C&D waste was approximately 252806.8 tons/year, and from private sector amount was more than 5000 tons/month. Results of laboratory experiments showed that cubic samples had highest compressive stress value of 51.95MPa.
4.2 BRICKS - Bricks are the important building material in the construction of residential as well as non -residential buildings. It is also a significant component of the total C&D waste on new residential construction sites. Bricks are largely treated as waste when broken or damaged from the brick production line or from construction site due to poor internal handling and excessive cutting. Brick is a maintenance-free component of the structure which is durable during the complete service life of the building. The high durability property of the brick makes it environmental friendly in the sense that after the demolition of the structure, it can be reused repeatedly and the left over volume which is non- reusable can be recycled for other beneficial purposes. During the demolition process itself, bricks obtained are stacked for next use in its original form after the removal of mortar which is chiselled out and make the brick ready for reuse or recycling, if not reusable. Bricks, after the removal of the stuck up mortar remain reusable for restoration or for new homes and projects. Recovered bricks can be used like a fresh lot of bricks without any further processing. These can also be laid on as brick pavers or for landscaping or any other artistic creations. Brick paved streets are aesthetically pleasing and rain water also percolates through the pavement. Also, a brick surface is cooler in hot months. These street advantages make bricks a good choice in driveways. Bricks on edge are also sometimes used as economical pavement solutions in smaller compounds.
ABSTRACT: Significant effort has been seen with upcycling or repurposing old materials such as soil, wood, metal, concrete etc. The concept of upcycling relates to the process of converting waste materials or useless products into new materials or products of better quality or better environmental value than in their previous use. This paper explores the challenges, opportunities that exist with the development of a recycled and reused building material market. This paper also seeks to address how issues behind secondary material in the life cycle of C&D wastes can be resolved by reusing and recycling techniques deemed problematic by local recyclers. The paper was developed using a variety of multidisciplinary resources within the field of solid waste management. It is hoped that the policy, regulation, circular economy recommendations within this paper be adopted as potential options for the municipality to address these issues.
The demolition is the most commonly pronounced word in the construction industry. As per the new building rules building should be demolished after its service period. Now-a-days the importance is given to sustainable and environmental friendly construction; there should be effective control of the demolitionwaste. The demolitionwaste can be reused for the construction. Construction and demolition (C and D) waste is defined as the solid waste generated by the construction, renovation, repair, alteration or demolition of residential, commercial, government or institutional buildings, industrial, commercial facilities and infrastructures such as roads, bridges, dams, tunnels, railways and airports. Construction and demolitionwaste is considered as high volume, low risk. It is commonly understood that this waste can be considered a resource, either for reuse in its original form or for recycling or energy recovery. Because of increasing waste production and public concerns about the environment, it is desirable to recycle materials from building demolition. If suitably selected ground cleaned appropriate industrial crushing in plants, these materials can be profitably used in concrete. Despite this, most Construction and Demolitionwaste ends up in landfills recycled aggregate and recycled sand that can be obtained. Further with the help of the obtained recycled material we intend to make various products such as concrete, paver blocks, hollow blocks, etc which will in turn be less costly as well. These recycled materials and products made from it are economical without any considerable change in the strength and durability aspect. Not only the cost effectiveness but it will also be aesthetically pleasing. According to Metropolitan region development authority the amount of construction and demolitionwaste (C&D waste) must be reduced by at least 70%. 3Rs model (Reduce, Reuse and Recycle) in the C&D waste management with costs savings.
The demolished aggregate is comparatively weaker than the natural aggregate against different mechanical actions. As per IS 2386 part (IV), the impact and crushing values for concrete wearing surfaces should not exceed 30% & for other than wearing surfaces 45% respectively. The crushing & impact values of recycled aggregate satisfy the BIS specifications limit. From crushing and impact test it is found that use of recycled aggregate is possible for application other than wearing surfaces.
During the last decades, the intense activity in the construc- tion sector within the European Union (EU) has generated huge volumes of construction and demolition (C&D) waste, precisely 890 million tonnes per year. On average, 50% of the C&D waste generated in EU is recycled (Tojo, Fischer 2011). However, this percentage is overrated because some countries consider mineral wastes, such as soil and stones not containing hazardous materials in their ratios. Accord- ing to this, EU State members are still far from achieving the quantitative target set by the Directive 2008/98/EC on Waste (Waste Framework Directive) for the year 2020. The reasons for this might include: high cost of C&D waste manage- ment, low cost of natural resources and landfill disposal, lack of knowledge regarding the consequences of waste, lack of interest by the clients for waste reduction or mini- mization, and lack of standards to regulate the inclusion of these wastes in the manufacturing of other materials.
Ox Mountain Landfi ll accepts loads of certain materials for reuse onsite. These materials are: asphalt, bricks, concrete, dirt, fi nes, rock, sand, soil, stone, untreated wood and yard waste. Loads with untreated wood and/or green waste mixed with inerts (asphalt, brick, concrete, dirt, fi nes, rock, sand, soil and stone) will not be sorted and therefore not recycled. However a load with mixed inerts only (asphalt, brick, concrete, dirt, fi nes, rock, sand, soil and stone) or mixed green waste only (untreated wood and yard trimmings) will be accepted for Alternative Daily Landfi ll Cover.
There is a growing awareness even in India about extensive damage being caused to the environment due to accumulation of waste materials from industrial plants, power houses, colliery pits and demolition sites. Use of waste products is not only a partial solution to environmental and ecological problems; it significantly improves the microstructure, and consequently the properties of concrete. Because of the above factors, there is a need and increasing demand for better understanding the behavior of waste material properties as well as better control of the microstructure developing in the construction material, to increase the durability. Following are
Central Road Research Institute (CRRI) carried out the “Feasibility study on the use of C&D waste in roadwork”. The study found potential feasibility for application in (a) embankment and sub-grade construction, (b) sub-base construction, (c) stabilized base course construction and (d) rigid pavement construction. But again this is not adopted on a magnificent scale. Also, another plausible use of C&D waste is in the manufacturing of recycled aggregates to replace with the natural ones in concrete . All these though have a great potential but not enough to tackle almost 50% of C&D waste that is generated in the form of bricks and concrete (Figure 2).