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Based on the shake table test on "tie column-ring beam-cast-in-place slab" construction waste recycled brick masonry structure, a 1/3 scaled model of 4 stories is tested to analyze the seismic behavior of the multi-storey masonry structure. The test is conducted with EL-Centro seismic wave, Taft wave and artificial wave to simulate the damages observed and the seismic response under different earthquake levels. On the basis of test results, the seismic performance of the model is good and the overall structure could satisfy seismic fortification requirements in the region of intensity 8. At the same time, there was no obvious difference between this masonry structure and recycled aggregate concrete block masonry structure. The lintel of the door and window damage seriously. The base damages more easily than the superstructure. Masonry structure with construction waste recycled brick can satisfy the requirement of the masonry structure buildings in eight degree of aseismatic design area.

Reuse of construction and demolition (C&D) waste as aggregates is becoming increasingly popular for a number of environmental and economic reasons. The purpose of this paper is to explore this topic.

In this study, structural‐ and pavement‐grade portland cement concrete (PCC) mixtures were developed using crushed recycled brick masonry from a demolition site as a replacement for conventional coarse aggregate. Prior to developing concrete mixtures, testing was performed to determine properties of whole clay brick and tile, as well as the crushed recycled brick masonry aggregate (RBMA), and a database of material properties was developed.

Concrete mixtures exhibiting acceptable workability and other fresh concrete properties were obtained, and tests were performed to assess mechanical properties and durability performance of the hardened concrete. Results indicated that recycled brick masonry aggregate concrete (RBMAC) mixtures can exhibit mechanical properties comparable to that of structural‐ and pavement‐grade PCC containing conventional coarse aggregates.

Results for durability performance were mixed, but additional testing to evaluate durability performance is recommended.

Although RBMAC has been untested in field applications, results of laboratory studies performed to date indicate that this material shows promise for use in pavement and structural applications. Future testing of RBMAC in both laboratory and field settings will allow stakeholders to gain a comfort level with its properties, identify specific potential uses, and establish guidelines that will assist in ensuring acceptable service life performance.

From the standpoint of sustainability, use of recycled materials as aggregates provides several advantages. Landfill space used for disposal is decreased, and existing natural aggregate sources are not as quickly depleted. Use of recycled aggregates in lieu of virgin quarried aggregates can potentially result in a lower embodied energy of the concrete, although this is often dependent on hauling costs. This particularly holds true if the methodology used to compute the embodied energy of a structure accounts for the “recovery” of energy at the end of its service life.

The United Nations has demonstrated a commitment to preserving the ecosystem through its 2030 sustainable development goals agenda. One crucial objective of these goals is to promote a healthy ecosystem and discourage practices that harm it. Building materials production significantly contributes to the emissions of greenhouse gases. This poses a threat to the ecosystem and prompts a growing demand for sustainable building materials (SBMs). The purpose of this study is to investigate SBMs to determine their utilization in construction operations and the potential impact their application could have on construction productivity.

A systematic review of the existing literature in the field of SBMs was conducted for the study. The search strings used were “sustainable” AND (“building” OR “construction”) AND “materials” AND “productivity”. A total of 146 articles were obtained from the Scopus database and reviewed.

Bio-based, cementitious and phase change materials were the main categories of SBMs. Materials in these categories have the potential to substantially contribute to sustainability in the construction sector. However, challenges such as availability, cost, expertise, awareness, social acceptance and resistance to innovation must be addressed to promote the increased utilization of SBMs and enhance construction productivity.

Many studies have explored SBMs, but there is a dearth of studies that address productivity in the context of SBMs, which leaves a gap in understanding. This study addresses this gap by drawing on existing studies to determine the potential implications that using SBMs could have on construction productivity.

Due to the high demand of concrete, significant volume of natural resources is required, including virgin aggregates. Many studies have shown that the production of concrete has one of the highest CO₂ levels. Although efforts are in place to recycle, enormous effects on landfill and the wider environment remain. Research has suggested the importance of reusing construction and demolition waste such as aggregate for use in recycled concrete. However, robust construction and demolition waste reduction strategies are required. There have been numerous researches on the use of recycled concrete and its management in the construction industry. This paper further consolidates this position.

This paper exhibits the barriers and benefits of using recycled aggregates for construction industry. This is achieved via reviewing the current construction and demolition waste reduction strategies used mainly in three countries: the UK, Australia and Japan. These countries were selected since they seemingly have similar construction industry and environment. Subsequently, evolving barriers and benefits of using recycled aggregates for construction industry are also reviewed and discussed. And to support such focus, robust construction and demolition waste reduction strategies will be advocated.

The findings are summarized as follows. The recycling construction and demolition waste could have a positive net benefit compared to the procurement and production of virgin aggregate materials with the same properties. This is not only financially beneficial but also environmentally viable, as fewer resources would be required to produce the same aggregate material. There are effective ways to achieve a high recycle rate target, as demonstrated by Japan. The implementation of a similar recycling process could be implemented globally to achieve a more effective recycle rate through the help of governments at all levels. By creating awareness about the financial and environmental benefits of using recycled aggregate products, large recycling companies can be also enticed to follow suit.

The findings from this paper can ultimately support the construction industry to further consolidate and advocate the use of recycled aggregates.

To achieve the research aim, this paper reviews some of the main sustainability factors of recycled aggregates (including coarse and fine aggregates) and provides comparison to virgin aggregates.

The improper evaluation and information management of circular economy (CE) (i.e. design, planning, supply chain, waste pile and material hazard) is critical for public health and is a major problem in the waste management of precast concrete (PC) building manufacture and construction and demolition wastes industry. The CE model is particularly problematic for PC building construction projects where the standard practices for the total number of waste building materials are not appropriate and do not match the safe disposal design specification, such as the recent number increase in the Malaysian illegal construction waste pile during the Movement Control Order (11 March 2021, about 5 out of 29 landfills related to states enforcing Act 672). The study aims to develop a framework application (i.e. Building Information Modelling [BIM]) that supports intelligent waste recycling management and sophisticated CE model system solutions.

Thus, the development of a new BIM-based programming algorithm approach is proposed for optimising CE in accordance with the needs of the current PC building construction schemes. As a precursor to this study, the concepts of CE practices are reviewed and the main features of BIM tools and techniques currently being employed on such projects are presented.

Sophisticated CE system solutions are described as an essential component of this optimisation to reduce the amount of waste generated at the end of the life cycle of PC building construction projects and to better manage the resources used throughout it.

Finally, the potential for a research framework for developing such a system in the future is presented.

A current trend is to use waste and by‐products in concrete to replace binders and aggregates. This trend reduces the impact on the environment and the use of finite natural resources. This paper aims to investigate whether concrete which includes crushed, graded and washed recycled construction demolition waste, used as a coarse aggregate, can be manufactured to a comparable strength as concrete manufactured from virgin aggregates.

Laboratory testing investigated the strength development of concrete manufactured with varying degrees of coarse aggregate replacement. All of the concrete samples were tested at five, seven, 14 and 21 days and the concrete with the recycled aggregate was compared to a plain control sample manufactured with virgin aggregates. The mixes tested against the control sample were: 100 per cent gravel replacement with recycled aggregate, and the same mix with a viscosity modifying agent. A 50 per cent partial coarse aggregate replacement was used in one batch to compare against the control and the 100 per cent recycled aggregate concrete. Compressive strength was used to compare the different concrete batch performance. Density was used to indicate the degree of particle packing and void content which was measured across the range of samples to evaluate the relationship between the different concrete mixes.

The optimum concrete mix design using recycled construction waste was obtained by using a 50‐50 per cent mix of virgin gravel and recycled aggregates. Using recycled construction waste as a 100 per cent coarse aggregate replacement produces concrete with a lower compressive strength when compared to concrete made with virgin aggregates.

The paper investigates ways of incorporating construction demolition waste as recycled aggregate to reduce the environmental impact of the production of concrete.

The capacity of landfills will reach saturation in the 2020s. There are more than 50,000 buildings in Hong Kong over 30 years old and which may require extensive refurbishment under the Mandatory Building Scheme. Additionally, most new owners/tenants tend to renovate their premises before moving in. Hence, there is an urgent need in Hong Kong, to explore strategies and measures to enable the development of effective refurbishment and renovation (R&R) waste management for such projects. The objectives of this paper are to investigate the process of R&R for identifying the perceived barriers and thereby the strategies for minimisation and management of R&R waste in Hong Kong.

Desktop study, semi-structured interviews, site observations and document reviews were used as the data collection methods to achieve the objectives of this research. Considering the nature and characteristics of the industry structure, the snowball sampling process was deployed for data collection. Thematic analysis and content analysis were used for data analysis. Waste minimisation and management strategies for R&R projects were then discussed and developed by the research team and a focus group meeting was held to validate the research findings. Six strategies were then proposed to the government.

R&R projects contribute 10–20% of the construction and demolition waste. The barriers to recycling of R&R waste can be grouped into six major categories: (1) lack of sorting and storage spaces, (2) high cost, (3) insufficient government supporting policy, (4) complicated recycling processes, (5) immature recycling market and (6) insufficient public education. Also, six strategies are proposed in this study, which include (1) pre-refurbishment audit, (2) development of recycling market, (3) sea reclamation, (4) incineration, (5) government support and (6) education and research.

The strategies and measures proposed in this research could most adequately serve as reference for the government officials, building professionals and academic researchers. Such knowledge would make possible the development of effective strategies and measures for minimising and managing R&R waste.

Introduction In a recent paper in this journal, Campbell outlined some of the techniques and problems associated with the demolition of existing structures and touched upon the possibility of recycling the debris from this process. This reflects the growing awareness among the general public, local authorities and central Government that the recycling of waste materials, from all sources, is both necessary and desirable. Indeed, according to a recently published report from the Trade and Industry Committee of the House of Commons: ‘The benefits of recycling are obvious: rarely do environ‐mental and economic factors so unambiguously support the same goal’.

In England and Wales, the construction industry produces 53.5 Mt of construction and demolition waste (C&D waste) annually, of which 51 percent goes to landfill, 40 percent is used for land reclamation and only 9 percent is crushed for future use or directly recovered. C&D waste may be contaminated, either through spillage from industrial processes or contact with contaminated land. There are no guidelines on how to classify C&D waste as contaminated or on risk management for contaminated C&D waste. Research at the UK Building Research Establishment and the University of Manchester has shown that new taxes are making disposal of C&D waste to landfill uneconomic, that low grade “land‐modelling” recycling is increasing, and that disposal on‐site is preferred. Sampling spatially of structures before demolition and temporally of processed C&D waste emerging from crushers is enabling sources of contamination and exceedance of guideline values to be compared with natural background levels. Improved sampling procedures and recommendations for risk assessment for the re‐use of C&D waste are being prepared.

It is a well-known fact that global warming is the extraordinary threat facing the world. The main reasons of these are human activities. Human beings have been contributing to the global warming in different ways for many years. Right material and product selection are some of the most important factors in the process of eliminating the negative effects of constructions on the natural environment and users. The life cycle of building materials involves the processes in which the products are extracted from the source. These processes are the stages of production, transportation, construction, use, demolition and destruction. Making wrong decisions in the selection and use of building materials may cause negative effects in the environment. The major purpose of this study is to to examine the embodied energy of of the traditional and comtemporary building materials according to the characteristics of the local climate. It will answer the question of; “What the embodied energy of a house was in the past and now” in Northern Cyprus. It will help to find out building materials with low embodied energy. There is no published database prepared for or in Northern Cyprus. In order to measure and evaluate the embodied energy of buildings and construction products in the world, there are no integrated systems in the Northern Cyprus at this point, while different countries have unique systems depending on the environmental, economic and social conditions of those countries. Measuring and controlling the environmental performance of environmental development is essential for the sustainable development of the Northern Cyprus.

By using the The Inventory of Carbon & Energy (ICE) program the embodied carbon statuses, embodied energy and transport energy and manufacture energy were discussed for each building material. As a result of this research it was found that locally produced or locally existing materials do not always give the best result in terms of embodied energy all the time. The energy consumption of building materials used in buildings and their associated carbon emissions will assist in the selection of environmentally friendly materials.