Ann T.W. Yu

Reducing building waste at construction sites in Hong Kong

The building industry is using a considerable amount of resources, but if the life cycle of the material on site is closely examined, it is generally known that there is a relatively large portion of the materials being wasted because of poor material control on building sites. The problem of material wastage is not an isolated issue on construction sites. It is also an environmental concern. Hong Kong is running out of both reclamation sites and landfill space for the disposal of construction & demolition (C&D) waste. Many resources can be conserved and the amount of C&D waste required to be disposed of should be greatly reduced if better management of materials is practiced on building sites. This paper reports on a recent study conducted in Hong Kong relating to material control on construction sites with high‐rise multi‐storey buildings. In the paper, the causes of building waste are identified and the wastage levels of various trades for public housing and private residential projects in Hong Kong are quantified. The role of material control in reducing building waste is then discussed in details under three headings, namely design, material procurement and handling, and site management and practices.

Quantifying construction and demolition waste: An analytical review

Quantifying construction and demolition (C&D) waste generation is regarded as a prerequisite for the implementation of successful waste management. In literature, various methods have been employed to quantify the C&D waste generation at both regional and project levels. However, an integrated review that systemically describes and analyses all the existing methods has yet to be conducted. To bridge this research gap, an analytical review is conducted. Fifty-seven papers are retrieved based on a set of rigorous procedures. The characteristics of the selected papers are classified according to the following criteria - waste generation activity, estimation level and quantification methodology. Six categories of existing C&D waste quantification methodologies are identified, including site visit method, waste generation rate method, lifetime analysis method, classification system accumulation method, variables modelling method and other particular methods. A critical comparison of the identified methods is given according to their characteristics and implementation constraints. Moreover, a decision tree is proposed for aiding the selection of the most appropriate quantification method in different scenarios. Based on the analytical review, limitations of previous studies and recommendations of potential future research directions are further suggested.

Application of value management in project briefing

Purpose – To describe a research project which seeks to establish a value management framework for project briefing to systematically identify and clarify client requirements, and represent these requirements precisely and explicitly to facilitate the design process.Design/methodology/approach – Two research instruments are used: structured questionnaire survey to validate the theoretical framework established; and experiments to test the proposed value management framework with real‐life projects, supported by case studies.Findings – The primary research findings of this project are the identification of 13 variables that have an impact on the briefing process, which form the basis of the theoretical framework. It is revealed that the theoretical foundation of the research supports the use of value management to the briefing process. Further validation will be completed by conducting questionnaire survey and real‐life case studies.Originality/value – This paper improves comprehension of the nature, chara...

Impact of Construction Waste Disposal Charging Scheme on work practices at construction sites in Hong Kong

Waste management in the building industry in Hong Kong has become an important environmental issue. Particularly, an increasing amount of construction and demolition (C&D) waste is being disposed at landfill sites. In order to reduce waste generation and encourage reuse and recycling, the Hong Kong Government has implemented the Construction Waste Disposal Charging Scheme (CWDCS) to levy charges on C&D waste disposal to landfills. In order to provide information on the changes in reducing waste generation practice among construction participants in various work trades, a study was conducted after 3 years of implementation of the CWDCS via a structured questionnaire survey in the building industry in Hong Kong. The study result has revealed changes with work flows of the major trades as well as differentiating the levels of waste reduced. Three building projects in the public and private sectors were selected as case studies to demonstrate the changes in work flows and the reduction of waste achieved. The research findings reveal that a significant reduction of construction waste was achieved at the first 3 years (2006-2008) of CWDCS implementation. However, the reduction cannot be sustained. The major trades have been influenced to a certain extent by the implementation of the CWDCS. Slight improvement in waste management practices was observed, but reduction of construction waste in the wet-finishing and dry-finishing trades has undergone little improvement. Implementation of the CWDCS has not yet motivated subcontractors to change their methods of construction so as to reduce C&D waste.

Investigating the determinants of contractor's construction and demolition waste management behavior in Mainland China.

The abundant generation of construction and demolition (C&D) waste presents a significant challenge to the sustainable development of the construction industry in Mainland China. As the implementer of construction activities, the contractors C&D waste management performance plays an important role in C&D waste minimization. This paper aims to investigate the determinants of the contractors C&D waste management behavior in Mainland China. The Theory of Planned Behavior (TPB) was selected as the basis of the theoretical model. In addition, three contextual constructs (i.e., economic viability, governmental supervision, and project constraints) were introduced, formulating the initial model. Based on the initial model, eight constructs were identified and seven hypotheses were proposed. A questionnaire survey was conducted to collect data and a Structural Equation Modeling (SEM) analysis was employed to test the proposed hypotheses. Results showed that the C&D waste management intention is not a significant determinant of contractors C&D waste management behavior. The most important determinant is economic viability, followed by governmental supervision as the second most important determinant. Nevertheless, the construct of project constraints is an insignificant determinant for contractors adoption of C&D waste management behavior. The research findings imply that, in Mainland China, the government, at this stage, plays an important role in guiding and promoting the contractor to exhibit better C&D waste management behavior.

Quantifying the Impact of Construction Waste Charging Scheme on Construction Waste Management in Hong Kong

AbstractA considerable amount of solid wastes is generated every year from construction and demolition (C&D) activities in Hong Kong. The C&D waste can be classified into inert and noninert wastes, in which the inert waste is normally disposed of in public fills as reclamation materials and the noninert waste is dumped at landfills. Under the current waste generation trend, all landfills and public fills in Hong Kong will be used up within a few years. To tackle this problem, in December of 2005, the Hong Kong Government implemented the Construction Waste Disposal Charging Scheme (CWDCS) to provide financial incentives to C&D waste generators to reduce waste and encourage reuse and recycling. This paper presents the results of a study to explore the perceptions of the Hong Kong construction participants toward the CWDCS after three years of implementation. The study was conducted by a survey with follow-up interviews to experienced professionals in the building industry. The results revealed no consensus ...

Strategies for risk management in urban–rural conflict: Two case studies of land acquisition in urbanising China

Abstract Urban and rural environments show clear differences in morphology, production mode and culture. With rapid urbanisation, these differences have become a major cause of urban–rural conflict. One of the most significant challenges arises from land acquisition, particularly in China, where cities have experienced substantial growth in the 21st century. Different types of risk are associated with land acquisition conflict in different Chinese cities. In this study, two types of cities are discussed: those with a historically low level of development but recent rapid economic growth, such as Yueqing; and cities that have maintained a relatively high level of development and experienced stable growth, such as Jiaxing. Land acquisition conflict in these two representative cities is then analysed in terms of property rights, access to resources and development. Analysis is performed at the institutional level to provide more accurate insights into the dynamics of conflict. The findings of the study suggest that different risk-management strategies are used in the two kinds of city, and that conflict is more likely to occur in cities with historically weaker development, such as Yueqing. To avoid such conflict, systematic risk-management strategies should be established in these cities.

Value management : recent developments and way forward

Purpose – The purpose of this paper is to review the development of value management (VM) over the last few decades and propose ways for future development.Design/methodology/approach – A qualitative research methodology was adopted which involved a comprehensive review of relevant literature leading to a better understanding of the history and development of VM. A way forward is suggested for the future development of VM.Findings – The research revealed that sustainable development is an area which has great potential for the application of a VM methodology in the construction industry in order to ensure sustainable design and development is leveraged during the life span of construction projects.Originality/value – The research work described in this paper encourages researchers and practitioners to integrate VM and sustainable development. It enables the VM community to have a better understanding of applying VM techniques to address “green building” issues and the potential of applying VM to promote s...

Problems and solutions of requirements management for construction projects under the traditional procurement systems

Purpose – This paper aims to focus on requirements management of projects constructed under traditional procurement system. It seeks to discuss the requirements management processes highlighting the limitations and addressing the need for a practical framework for facilitating the implementation of requirements management in the construction industry.Design/methodology/approach – Two research instruments were used in this paper: semi‐structured interviews and case studies.Findings – The literature review introduced a generic process for requirements management practice potentially to be adopted in the construction industry. The research study identified that the processes and limitations of current practice included the lack of a practical framework, misinterpretation of requirements, difficulties in identifying requirements, conflicts between expectation and constraints, complex hierarchy of clients organisation and communication problems in eliciting client requirements. Recommendations are given that ...

An analytical review of briefing practice in the Hong Kong construction industry

Abstract A comprehensive client brief is essential to achieve the target time, cost and quality for a construction project. Although various attempts have been made to improve the current practice of briefing, it is still considered as inadequate by many researchers. In Hong Kong, very limited research work has been conducted to investigate the briefing process. This paper aims to present the key findings of a research, which analysed the practice and problems of briefing. Literature review, focus group interviews and a questionnaire survey were adopted to conduct the research. The findings implicate that a comprehensive framework for briefing should be established for systematic identification and clarification of client requirements, and precise and explicit representation of these requirements. It is suggested that this framework should include the stages and time frame of briefing, identification and representation of stakeholders to be involved in briefing, a systematic approach for identification, clarification and representation of client requirements, change management of requirements and management tools to be adopted in the briefing process and the format of a comprehensive client brief.