17 research outputs found
Waste-Efficient Materials Procurement for Construction Projects: A Structural Equation Modelling of Critical Success Factors
Albeit the understanding that construction waste is caused by activities ranging from all stages of project delivery process, research efforts have been concentrated on design and construction stages, while the possibility of reducing waste through materials procurement process is widely neglected. This study aims at exploring and confirming strategies for achieving waste-efficient materials procurement in construction activities. The study employs sequential exploratory mixed method approach as its methodological framework, using focus group discussion, statistical analysis and structural equation modelling. The study suggests that for materials procurement to enhance waste minimisation in construction projects, the procurement process would be characterised by four features. These include suppliers’ commitment to low waste measures, low waste purchase management, effective materials delivery management and waste-efficient Bill of Quantity, all of which have significant impacts on waste minimisation. This implies that commitment of materials suppliers to such measures as take back scheme and flexibility in supplying small materials quantity, among others, are expected of materials procurement. While low waste purchase management stipulates the need for such measures as reduced packaging and consideration of pre-assembled/pre-cut materials, efficient delivery management entails effective delivery and storage system as well as adequate protection of materials during the delivery process, among others. Waste-efficient specification and bill of quantity, on the other hand, requires accurate materials take-off and ordering of materials based on accurately prepared design documents and bill of quantity. Findings of this study could assist in understanding a set of measures that should be taken during materials procurement process, thereby corroborating waste management practices at other stages of project delivery process
Changing Significance of Embodied Energy: A comparative study of material specifications and building energy sources
Despite the increasing significance of embodied impacts of buildings, efforts to reduce their environmental footprints have been concentrated on the operational impacts of buildings. This study investigates the changing significance of embodied carbon over the entire life cycle of whole buildings. A case study of an office building was modelled with Revit, and sensitivity analyses of the modelled building were performed by varying the material specification and energy use pattern for seven other typologies. Using Revit, BIMWASTE tool, ATHENA Impact Estimator and Green Building Studio, comparative life-cycle analyses were carried out for the eight building typologies. The study suggests that notwithstanding the enormous impacts of the operational stage on life-cycle carbon of fossil fuel-based buildings, embodied impacts could vary between 8.4 and 22.3%. A key determinant of the proportional impacts of embodied energy is the nature of materials used for building construction. Similarly, embodied impacts of buildings become more significant and could contribute up to 60% of their life cycle impacts as they become more energy-efficient during their operational stage. As the study confirms the varying significance of embodied energy as construction materials and energy use patterns change, it implies the need for policy measures based on a whole life assessment methodology, instead of the usual ways of giving sole importance to the operational impacts of buildings. With buildings becoming more energy-efficient during their operational stage, there is an urgent need for an increased focus on the embodied impacts of buildings, especially as renewable energy resources are becoming widely adopted
Critical Design Factors for Minimising Waste in Construction Projects: A Structural Equation Modelling Approach
Notwithstanding that efforts made at the design stage of building construction projects have significant impacts on project outcome, most waste management efforts are usually focussed on construction stage. This is albeit the understanding that construction waste could be significantly reduced through design activities. This study investigates the underlying design measures that are capable of minimising waste generated by construction and demolition activities. Using exploratory sequential mixed method research, the study employs focus group discussions and thematic analysis at the exploratory phase, while questionnaire and structural equation modelling were used at the explanatory stage of the study. The study suggests that construction waste could be significantly reduced by designing for standard materials size and by designing for modern method of construction, thereby minimising waste due to breakage, materials leftover and other major causes of waste. The study further suggests that the design process and design documentation are key underlying measures for mitigating waste in construction projects. This could be enhanced through such critical success factors as a collaborative delivery process, which is characterised by early involvement of contractors and adequate coordination of design between various disciplines involved. Findings of this study would assist designers and other construction stakeholders in understanding the significant measures for designing out waste in construction projects
Life cycle environmental performance of material specification: a BIM-enhanced comparative assessment
This study aims to evaluate the extent to which building material specification affects life cycle environmental performance, using a building information modelling (BIM)-enhanced life cycle assessment (LCA) methodology. A combination of the BIM-based design and analysis tool Revit Architecture, the energy simulation tool Green Building Studio (GBS) and the LCA tool ATHENA Impact Estimator were used for the assessment. The LCA was carried out on a life case study of a 2100 m2 two-floor primary-school building, as well as a variability analysis, by varying the material specification in terms of whole building materials. The life cycle performance of the buildings was primarily evaluated in terms of its global warming potential (GWP) and health impact.
The findings of the study show that irrespective of the materials used, buildings that are based on renewable energy perform better than those based on fossil fuels over their life cycle. In terms of building materials, both environmental and health preferences of buildings congruently range from timber, brick/block and steel to insulated concrete formwork (ICF), in descending order. The study suggests that as buildings become more energy efficient during operational stages, serious attention needs to be given to their embodied impact.
The study lays out a methodological framework that could be adopted by industry practitioners in evaluating life cycle environmental impact of different BIM-modelled material options at the building conception stage. This has the tendency to ensure that the highest proportion of life cycle environmentally beneficial material combinations are selected during specification and construction
Optimising material procurement for construction waste minimization: An exploration of success factors
Although construction waste occurs during the actual construction activities, there is an understanding that it is caused by activities and actions at design, materials procurement and construction stages of project delivery processes. This study investigates the material procurement and logistics measures for mitigating waste generated by construction activities. In a bid to explore the phenomenon from the perspectives of experts from the construction industry, this study used a combination of descriptive interpretive research and survey approach as its methodological framework. The study suggests that four features characterised waste efficient logistic and procurement process. These include suppliers' commitment to low waste measures, low waste purchase management, effective materials delivery management and waste efficient Bill of Quantity. In addition, the key requisite strategies for mitigating construction waste through materials procurement include commitment to take back scheme , procurement of waste efficient materials/technology and use of minimal packaging. The use of Just-in-Time (JIT) delivery system and prevention of over ordering are also important for mitigating waste through materials procurement processes. These implies that while the key measures are critical success factors for reducing waste through procurement process, the four established features are required of all procurement process. Measures through which the procurement process could enhance waste efficiency are further highlighted and discussed in the paper. Findings of this study could assist in understanding a set of measures that should be taken during materials procurement process, thereby corroborating waste management practices at design and construction stages of project delivery process
A framework for big data analytics approach to failure prediction of construction firms
This study explored use of big data analytics (BDA) to analyse data of a large number of construction firms to develop a construction business failure prediction model (CB-FPM). Careful analysis of literature revealed financial ratios as the best form of variable for this problem. Because of MapReduce’s unsuitability for iteration problems involved in developing CB-FPMs, various BDA initiatives for iteration problems were identified. A BDA framework for developing CB-FPM was proposed. It was validated by using 150,000 datacells of 30,000 construction firms, artificial neural network, Amazon Elastic Compute Cloud, Apache Spark and the R software. The BDA CB-FPM was developed in eight seconds while the same process without BDA was aborted after nine hours without success. This shows the issue of not wanting to use large dataset to develop CB-FPM due to tedious duration is resolvable by applying BDA technique. The BDA CB-FPM largely outperformed an ordinary CB-FPM developed with a dataset of 200 construction firms, proving that use of larger sample size with the aid of BDA, leads to better performing CB-FPMs. The high financial and social cost associated with misclassifications (i.e. model error) thus makes adoption of BDA CB-FPMs very important for, among others, financiers, clients and policy maker
Waste effectiveness of the construction industry: Understanding the impediments and requisites for improvements
© 2015 Elsevier B.V. All rights reserved.Construction industry contributes a large portion of waste to landfill, which in turns results in environmental pollution and CO2 emission. Despite the adoption of several waste management strategies, waste reduction to landfill continues seeming an insurmountable challenge. This paper explores factors impeding the effectiveness of existing waste management strategies, as well as strategies for reducing waste intensiveness of the construction industry. Drawing on series of semi structured focus group discussions with experts from the UK leading construction companies, this paper combines phenomenological approach with a critical review and analysis of extant literatures. Five broad categories of factors and practices are responsible for ineffectiveness of construction and demolition waste management strategies, which subsequently results in waste intensiveness of the industry. These include end of pipe treatment of waste, externality and incompatibility of waste management tools with design tools, atomism of waste management strategies, perceived or unexpected high cost of waste management, and culture of waste behaviour within the industry. To reduce waste intensiveness of the construction industry, the study suggests that six factors are requisites. These are tackling of waste at design stage, whole life waste consideration, compliance of waste management solutions with BIM, cheaper cost of waste management practice, increased stringency of waste management legislation and fiscal policies, and research and enlightenment. The proposed strategies are not only important for achieving low waste construction projects, they are important for reducing waste intensiveness of the construction. Implementation of the suggested measures would drive waste management practices within the construction industry
Are sustainable buildings healthy? An investigation of lifecycle relationship between building sustainability and its environmental health impacts
Critical Success Factors (CSFs) for Ensuring Bankable Completion Risk in PFI/PPP Mega Projects
This study investigates project financiers’ perspectives on the bankability of completion risk in Private Finance Initiatives and Public Private Partnerships (PFI/PPP) mega projects. Using a mixed methodology approach, focus group discussions with financier stakeholders in UK’s PFI/PPP industry were used to identify 23 criteria relevant for evaluating completion risk in funding applications. These criteria were put in a questionnaire survey to wider audiences of financiers of PFI/PPP projects in the UK. Series of statistical tests were performed, including Reliability Analysis, Kruskal-Wallis Non-Parametric Test, Descriptive Statistics, Principal Rank Agreement Factor (PRAF) and Regressions Analysis. After identifying 21 reliable criteria influencing the bankability of completion risk, the general agreement of three major financier stakeholders (Senior Lenders, Equity Financiers and Infrastructure Financiers) on all the criteria were examined through Kruskal-Wallis test and PRAF. A regression model, constructed and validated with input from another team of expert financiers, revealed five key criteria influencing the bankability of completion risk in PPP mega projects. These include (1) Construction contractor with years of experience of successful completion of mega projects, (2) Construction Contractor’s financial strength, (3) Existence of Tried-and Test Technology for the construction of project, (4) Availability of Independent Technical Consultant (ITC) and (5) Existence of Fixed Price Turn Key (FPTK) construction contract. The research findings will provide PFI/PPP contractors and clients with valuable strategies for satisfying financiers’ requirements in delivering large-scale Infrastructure PPP project
Conversational artificial intelligence in the AEC industry: A review of present status, challenges and opportunities
The idea of developing a system that can converse and understand human languages has been around since the 1200 s. With the advancement in artificial intelligence (AI), Conversational AI came of age in 2010 with the launch of Apple’s Siri. Conversational AI systems leveraged Natural Language Processing (NLP) to understand and converse with humans via speech and text. These systems have been deployed in sectors such as aviation, tourism, and healthcare. However, the application of Conversational AI in the architecture engineering and construction (AEC) industry is lagging, and little is known about the state of research on Conversational AI. Thus, this study presents a systematic review of Conversational AI in the AEC industry to provide insights into the current development and conducted a Focus Group Discussion to highlight challenges and validate areas of opportunities. The findings reveal that Conversational AI applications hold immense benefits for the AEC industry, but it is currently underexplored. The major challenges for the under exploration were highlighted and discusses for intervention. Lastly, opportunities and future research directions of Conversational AI are projected and validated which would improve the productivity and efficiency of the industry. This study presents the status quo of a fast-emerging research area and serves as the first attempt in the AEC field. Its findings would provide insights into the new field which be of benefit to researchers and stakeholders in the AEC industry