Design waste mapping: a project life cycle approach

An ever-increasing amount of global research on construction waste has been conducted over the past two decades, ranging from ‘soft’ mapping and management, reduction tools and methodologies to ‘hard’ material and recycling technologies. However, the current state of research is largely dominated by endeavours to manage waste that has already been produced. Hence, there is a need for a shift from ‘end-of pipe’ solutions that focus on on-site waste management to a source-based approach that is aimed at ‘life cycle’ analysis. This research engaged a sample population from the major UK architectural and contracting firms through 24 interviews to investigate the underlying origins, causes and sources of waste across all project life cycle stages. Respondents reported that designing out waste has never been the most glamorous end of sustainable design. Moreover, the results reveal that waste generation is affected by a wide practice of not embedding waste reduction in briefing and contractual documents, no baseline setting, and lack of designers’ understanding of design waste origins, causes and sources. This is hindered by limited know-how and incoherent coordination and communication between project members and impeded by time constraints and disjointed design information. Collectively, these impediments disallow the consideration, engagement and implementation of designing out waste

Innovation in cleaner production through waste recycling in composites

Purpose: At present Glass Reinforced Plastic (GRP) waste recycling is very limited due to its intrinsic thermoset composite nature and non-availability of viable recovery options. The purpose of this paper is to assess the recycling potential of GRP waste powder and fibre in concrete, cement and rubber composites. Design/methodology/approach: Extensive laboratory experiments were conducted to examine the suitability of GRP waste in concrete, cement, and rubber composites. GRP waste samples were processed and suitable tests were performed to measure the mechanical properties of the resulting three composites. Findings: The findings of this experimental investigation confirmed that GRP waste can be used as a partial replacement for virgin and raw materials in composites. Furthermore, the addition of GRP waste powder and fibre to composites has the potential to improve their mechanical properties. Research limitations/implications: Results show that the use of GRP waste powder in concrete and rubber composites and GRP waste fibre in architectural cladding panels has technical, economic and environmental benefits. As such, the findings of this research pave the way for viable technological options for substituting quality raw materials by GRP waste in pan-industry composites and improving their mechanical properties. However, resulting recycled composites depend upon the consistency and quality of GRP waste powder and fibre, and the access to specialised composite material manufacturing facilities. Furthermore, full compliance tests including durability studies and requirements, which may depend upon specific applications, are recommended. Practical implications: The adopted methodological approach of this research and subsequent experimental results pave the way for viable technological options for substituting quality raw materials by GRP waste in pan-industry composites. It is anticipated that the results of this research would help diverting GRP waste from landfill to more useful industrial applications. Originality/value: Growing technological innovations, ample market value and demand for GRP composites all over the world has trigged interest in optimising GRP waste recovery. However, few solutions for GRP waste recycling into value-added industrial products are being explored. The work reported so far is very limited and did not show viable applications for GRP waste composites. Hence, this research sets out to examine the suitability of GRP waste powder and fibre in concrete, cement, and rubber composites. © Emerald Group Publishing Limited

Integration of waste minimisation strategies into the design process of buildings

The construction industry is by far the greatest consumer of resources and waste producer of all industries in the UK; being responsible for 32% of total waste generation, which equates to three times the combined waste produced by all households. Consequently, construction waste management and minimisation became a priority in the EU and UK environmental policy programmes resulting in a combined plethora of government-driven waste related legislation and guidance documents to curb construction waste production. Similarly, an ever-increasing global research on construction waste has been conducted over the last decade ranging from ‘soft’ onsite waste auditing tools and methodologies to ‘hard’ material and recycling technologies. However, the current state-of-research is largely dominated by endeavours to manage waste that has already been produced. Very few studies have been undertaken on how architects could go about minimising waste through a change in design practices. Hence, this research set out to construct and validate a Designing out Waste (DoW) Framework to assist architects in embedding design waste reduction strategies in each design stage. [Continues.

An Assessment of the Compressive Strength of Glass Reinforced Plastic Waste Filled Concrete for Potential Applications in Construction

Efforts were made to recycle Glass reinforced plastic (GRP) waste powder in concrete products and assess its compressive strength to comply with British Standards for use in construction applications. More than 90 GRP waste-filled concrete specimens were developed using the concentration of 5%, 15%, 30% and 50% (w/w). The findings revealed that the increase in concentration of GRP waste decreased the compressive strength. However, increase in curing duration resulted in improving the compressive strength of concrete. The findings of this work pave the way for further GRP waste recycling in precast construction products for use in various applications

Investigation into contractors' responsible sourcing implementation practice

Over the last few years there has been an increasing demand for more efficient ways of procuring materials in terms of reducing their impacts on the environment. The UK Strategy for Sustainable Construction introduced a voluntary target of 25% of all resources in the construction industry to be responsibly sourced by 2012. At the time of writing there has been very limited research on responsible sourcing (RS), particularly in terms of contractors' current practices and implementation at project level. Therefore, an assessment of the current status of RS among the top 100 UK contractors has been captured using a questionnaire survey and follow-up interviews. The results indicate that no clear RS responsibility has been established, and there is no cohesive, top-down strategy from the strategic level (sustainability managers) to the implementation level (procurement mangers) in place in contracting companies. On the other hand, there was agreement that government leadership through the implementation of RS in all public projects could be a significant catalyst to drive RS in construction projects

Feasibility of zero carbon homes in England by 2016: a house builder's perspective

The UK government set itself a 60 per cent reduction of carbon dioxide emissions target on 2000 levels by 2050. This commitment will require carbon reductions to be made by all industries including the housing sector which presently accounts for 27 per cent of carbon dioxide emissions. The house building industry is the subject of numerous government policies and legislation, but none are as demanding as the Code of Sustainable Homes, which set a ‘world-beating’ target for all new homes to be zero carbon by 2016. This paper sets out to investigate the feasibility of building zero carbon homes in England by 2016 from a house builder’s perspective. A comprehensive opinion of the feasibility of zero carbon homes is gathered through a questionnaire survey and in-depth semi-structured interviews with the major UK housing developers. The research found that there are currently numerous legislative, cultural, financial and technical barriers facing house builders to deliver zero carbon homes in England by 2016..The surveyed house builders concurred that these challenges are not insurmountable provided that a swift, all-embracing and above all realistic strategy is adopted and implemented across the supply chain

Reducing construction waste in healthcare facilities: a project lifecycle approach

The NHS has one of the largest property portfolios in the UK, comprising hospitals, clinics, dental offices, out-patient surgery centres, birth centres and nursing homes. Additionally, it is experiencing historic levels of growth with the largest programme of investment the country has ever seen where 25 per cent of hospitals are being replaced or upgraded; 100 new hospitals to be constructed by 2010; and 3000 GP premises being built/replaced/refurbished. As a result, a significant number of environmental concerns and challenges need to be addressed, namely the reduction of water and energy consumption, and more significantly waste generation. In the UK, construction of healthcare facilities creates over 350,000 tonnes of waste, which is about 20 per cent of all generated waste in the UK. Construction waste generation is a global issue and several studies have been performed in different parts of the world to develop methods and tools for waste prevention, reduction, reuse and recycling. However, many of these studies adopted a linear approach by focussing on a specific project phase, such as design, procurement or construction, and a more integrated approach is required to holistically assess and evaluate waste causes and origins throughout the project lifecycle. Hence, this paper, part of a doctoral study, sets out to develop a life cycle construction waste mapping for healthcare facilities. An in-depth literature review has been conducted to identify the extent of the problem and provide a foundation for the PhD study that aims to develop a project lifecycle strategy for reducing construction waste in healthcare facilities. The paper concludes that construction waste is generated throughout the project lifecycle covering design, procurement, construction and demolition. However, literature revealed that there are a number of unique characteristics related to the construction and operation of healthcare facilities if compared with typical buildings, which is mainly due to their organisational and functional complexities. Hence, there is a need to develop a bespoke lifecycle waste mapping in healthcare buildings

An investigation of design waste causes in construction

The construction, demolition and excavation waste arising in the UK is estimated at 109 million tonnes per year. Much had been published on ways to improve on-site waste management and recycling activities but very few attempts made to address design generated waste. This paper examines previous studies on architects’ approach towards construction waste minimisation; and by means of a postal questionnaire sent to the 100 top UK architectural practices, investigates: the origins of design waste; waste minimisation design practices in the UK; and barriers to design out waste. The findings reveal that architects consider that waste is mainly produced during site operations and rarely generated during the design stages. However, about one third of construction waste could essentially arise from design decisions. Results also indicate that a number of constraints, namely: lack of interest from clients and attitudes towards waste minimisation are seen as disincentives to a proactive and sustainable implementation of waste reduction strategies during the design process

Spectrum and transmission range aware clustering for cognitive radio ad hoc networks

Cognitive radio network (CRN) is a promising technology to overcome the problem of spectrum shortage by enabling the unlicensed users to access the underutilization spectrum bands in an opportunistic manner. On the other hand, the hardness of establishing a fixed infrastructure in specific situations such as disaster recovery, and battlefield communication imposes the network to have an ad hoc structure. Thus, the emerging of Cognitive Radio Ad Hoc Network (CRAHN) has accordingly become imperative. However, the practical implementation of CRAHN faced many challenges such as control channel establishment and the scalability problems. Clustering that divides the network into virtual groups is a reliable solution to handle these issues. However, previous clustering methods for CRAHNs seem to be impractical due to issues regarding the high number of constructed clusters and unfair load distribution among the clusters. Additionally, the homogeneous channel model was considered in the previous work despite channel heterogeneity is the CRN features. This thesis addressed these issues by proposing two clustering schemes, where the heterogeneous channel is considered in the clustering process. First, a distributed clustering algorithm called Spectrum and Transmission Range Aware Clustering (STRAC) which exploits the heterogeneous channel concept is proposed. Here, a novel cluster head selection function is formulated. An analytical model is derived to validate the STRAC outcomes. Second, in order to improve the bandwidth utilization, a Load Balanced Spectrum and Transmission Range Aware Clustering (LB-STRAC) is proposed. This algorithm jointly considers the channel heterogeneity and load balancing concepts. Simulation results show that on average, STRAC reduces the number of constructed clusters up to 51% compared to conventional clustering technique, Spectrum Opportunity based Clustering (SOC). In addition, STRAC significantly reduces the one-member cluster ratio and re-affiliation ratio in comparison to non-heterogeneity channel consideration schemes. LB-STRAC further improved the clustering performance by outperforming STRAC in terms of uniformity and equality of the traffic load distribution among all clusters with fair spectrum allocation. Moreover, LB-STRAC has been shown to be very effective in improving the bandwidth utilization. For equal traffic load scenario, LB-STRAC on average improves the bandwidth utilization by 24.3% compared to STRAC. Additionally, for varied traffic load scenario, LB-STRAC improves the bandwidth utilization by 31.9% and 25.4% on average compared with STRAC for non-uniform slot allocation and for uniform slot allocation respectively. Thus, LB-STRAC is highly recommended for multi-source scenarios such as continuous monitoring applications or situation awareness applications

Construction waste minimisation in the UK healthcare industry

Over recent years, there has been considerable growth in healthcare infrastructure investment throughout Europe where billions of Euros are invested in new and refurbished healthcare facilities. In the UK, capital expenditure on healthcare has increased from around £1.1 billion in 1997/98 to around £5.5 billion in 2007/08; an increase in real terms of almost four times the expenditure in 1997. As a result, several environmental concerns and challenges, including construction waste generation, have emerged. There is a consensus in the literature that factors causing construction waste span the project life cycle, however, healthcare facilities have different features compared to other buildings due to functional and operational complexities. By means of a questionnaire followed by interviews with construction industry practitioners specialising in healthcare facilities, this paper aims to identify the level of importance given in the healthcare industry to minimising construction waste; recognising the effect on construction waste generation due to complexity and special features of healthcare facilities; exploring causes of waste particular to the healthcare lifecycle and to examining the waste minimisation strategies used in the industry. The findings revealed that lifecycle waste mapping in healthcare facilities is similar to other types of buildings. Results also indicate that waste management is not treated as a priority in the briefing and design stages of most healthcare facilities and is still seen as the responsibility of the contractor. Initiating waste minimisation practices at the construction stage inevitably results in loosing a number of effective waste reduction opportunities at the beginning of the project. The findings from this research contributes to a growing body of literature on sustainable healthcare construction and to support NHS policy on ‘greening the environment’ through reduction of construction waste. This paper concludes that a more integrated lifecycle approach is required to effectively reduce healthcare construction waste