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Traditionally, construction and demolition waste (CDW) materials have been considered to be unwanted, surplus, or wastage materials or materials with zero value. Such a conceptualisation only embraces a negative aspect, which underpins the disposal of reusable and recyclable CDW materials in landfills, thus damaging the circular economy and the environment. The scope of this research was to conceptualise the circular economy potential of non-hazardous construction and demolition waste, which can be used as a resource for advancing the circular economy and sustainability in the built environment. Thus, the abbreviation 'CEPCDR' is used for this purpose. The study employs an integrative literature review to understand in depth whether the rationale in the existing CDW definitions advocates for the circular economy. Instead, the literature showed that the current definitions mainly support quantitative, economic, or classification needs, respectively. That is because they lack consideration of the dynamic nature of CDW materials, which embraces the spatial and temporal dimensions. The former involves the geographic context in which the CDW phenomenon eventuates, while the latter concerns the lifecycle of materials. This study contributes to the body of knowledge by conceptualising the CEPCDR using a holistic approach that includes five dimensions: the social, economic, environmental, spatial, and temporal perspectives. Furthermore, the study seeks to drive future research in measuring the CEPCDR. [ABSTRACT FROM AUTHOR]

The construction industry is one of the major producers of municipal solid waste. Although there are many studies in municipal solid waste management, the research on the recovery of recyclable building material from construction sites remains limited. This paper addresses the optimal design issue of the construction and demolition (C&D) waste logistics network based on the features of the construction industry from the contractors' perspective. The purpose of this paper is to provide an optimal C&D waste recycling network decision (RND) model considering the change of construction sites location over time. A multi-period and multi-objective mixedinteger linear programming model was developed to minimize the cost of C&D waste disposal for contractors, and to minimize the carbon emissions from C&D waste transportation. An application study was conducted to assess the performance of the RND model. Through some sensitivity analysis experiments based on an immune genetic algorithm, the influences of environmental policies and carbon tax policy on improving the recycling rate of C&D waste and reduce the carbon emission were explored. The findings of this research suggest that: (1) a RND model with the feature of the construction industry developed in this paper can effectively optimize the C&D waste logistics network; (2) government policies and laws are valid political instruments to improve the recycling rate of C&D waste; (3) the carbon-tax analyses demonstrate that a carbon tax policy can effectively reduce carbon emissions. [ABSTRACT FROM AUTHOR]

Risk-compensation behavior refers to the riskier behavior resulting from the perception that the environment has become safer. This study aims to investigate the role of demographics and psychological constructs in predicting construction workers' tendencies to engage in risk-compensation behaviors. Data were collected using a structured questionnaire. The participants include 88 roof tilers in New South Wales, Australia. By using the structural equation modeling (SEM) technique with partial least-squares estimation (PLS), the authors found that workers' tendencies to engage in risk-compensation behaviors are influenced by both demographics (e.g., work experience, education level, and negative safety experience) and psychological constructs (e.g., optimism, internal locus of control, trait worry, and habit), and that the effects of demographics were mediated by the psychological constructs. The findings imply that overconfidence about own capability and perceived power of control over safety issues may encourage risk-compensation behaviors on construction sites. The structural model developed in this study may help people to understand the important mental processes that may influence potential behavioral changes when people perceive that they are more protected. [ABSTRACT FROM AUTHOR]

The construction industry has been facing a paradigm shift to integrate new construction requirements, most notably the development of advanced technologies, such as environmental management, information technology, and building information modeling. Timely curriculum reform is therefore necessary for construction education to adapt quickly to the paradigm shift. The aim of this paper is to investigate the gaps between educational attainment and job requirements in the Australian construction industry, based on which further curriculum reform can be conducted. A survey is administered to 252 construction graduates. The results suggest that the most significant gaps are related to technical skills for construction and problem-solving skills. The gaps can be categorized into eight groups based on an exploratory factor analysis. The eight groups are construction technology, information technology, problem-solving skills, construction economics, risk management, basic theories, business management, and sustainability science. It is therefore recommended that curriculum reform be conducted to bridge the gaps between educational attainment and job requirements to prepare construction graduates for the competitive and fast-changing construction environment. [ABSTRACT FROM AUTHOR]

This study aims to investigate the minimum voluntary safety investment through optimization of total controllable safety costs for building projects. A correlational research study was designed to achieve the research aim. Data were collected using multiple techniques from 47 completed building projects in Singapore. The curves for describing the relationships between voluntary safety investment, total accident costs, accident frequency rate, and total controllable safety costs were developed using regression techniques. The optimization of voluntary safety investment was conducted using the extreme-value theorem with the objective of finding the minimum level of total controllable safety costs. The results show that the financially minimum voluntary safety investment varies with different levels of safety culture and project hazard. The models developed in this study can be used to estimate the minimum voluntary safety investment for building projects at different safety culture and project hazard levels. The findings of this study may provide the basis for financial decision making in managing construction safety for building contractors. [ABSTRACT FROM AUTHOR]

The construction industry has considerable environmental impacts through the process of manufacturing building materials and building construction. Many environmental labelling programs have been introduced to the construction industry to measure the environmental impacts, including building up the environmental profiles for building materials. Although absolute measurements of the environmental impacts can be obtained by these labelling programs through detailed Life Cycle Assessment (LCA) studies, relative measurements should not be overlooked to indicate the gap between the current and the "leanest" performance. The term "lean" is often used to describe a process with less wastes, materials, human effort, time, etc. The lean concept originates from the Toyota Production System and has been applied in the automobile industry for decades. This paper therefore aims to investigate the applicability of a relative measurement of the environmental impacts for building materials by introducing the concept of "lean score". The research aim is narrowed down by choosing the carbon labelling program and the precast concrete products as research objectives. The results indicate that a "lean" benchmark can be built to offer relative measurements of carbon emissions for precast concrete products. The lean score obtained from the benchmarking process provides the improving potential that can help the construction industry move towards sustainability. The results are also useful for regulatory bodies to establish national standards to measure the environmental impacts for building materials. [ABSTRACT FROM AUTHOR]