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Theme: 3R as an Economic Industry- Next Generation 3R Solutions for a Resource Efficient Society and Sustainable Tourism Development in Asia and the Pacific ; Parallel Roundtable 2: Economic Opportunities through 3R ~ Construction and Demolition Waste: Country/Private Sector Presentations –Business Case Experiences ; Jointly organized by Government of Maldives Ministry of Tourism, Government of Maldives Ministry of the Environment, and Government of Japan Ministry of the Environment and United Nations Centre for Regional Development (UNCRD) ; published_or_final_version

Construction waste management (CWM) has received worldwide attention for some time. As a result, a plethora of research, investigating a wide array of CWM issues such as their profiles, practices, and performance, has been reported in individual economies around the globe. However, a cross-jurisdictional comparison of these issues is limitedly presented in the literature despite its importance to benchmarking performance and identifying best CWM practices in the context of globalization whereby knowledge sharing has already transcended traditional country boundaries. The aim of this ex post facto research is to compare CWM profiles, practices, and performance in Australia, Europe (Europe refers to EU-27 member countries in the European Union, including Belgium, France, Germany, Italy, Luxembourg, Netherlands, Denmark, Great Britain, Ireland, Portugal, Spain, Greece, Austria, Finland, Sweden, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, Slovenia, Malta, Cyprus, Bulgaria, and Romania.), Hong Kong, and the United Kingdom at a national-level, with a view to facilitating CWM knowledge sharing internationally. It does so by triangulating empirical data collected from various national statistical yearbooks with research papers and professional reports on CWM in these economies. It is found that in producing one million (US) dollars' work, construction contributes a volume of solid waste ranging from 28 to 121 tons among countries. Conscientious CWM practices can make a significant difference in reducing, reusing, or recycling construction waste, as evident in the large variation in the CWM performance. While it might be oversimplified to conclude that the best practices in one country can be applied in another, the research provides insightful references into sharing CWM knowledge across boundaries. ; published_or_final_version

The enormous amount of construction activity in China associated with its rapid economic development has produced a large amount of construction and demolition (C&D) waste over the past three decades. The majority of this waste has not been well processed, which has led to severe damage to the environment. Although there is clearly a need for better C&D waste management (WM) in China, the best ways to achieve this have yet to be fully explored. This paper is based on a study by the authors that aimed to identify the Critical Success Factors (CSFs) for C&D WM in China. A questionnaire survey and 14 semi-structured interviews with practitioners, researchers and government officials were conducted in Shenzhen, a leading city in southern China for tackling C&D WM. Seven factors were identified as the CSFs for managing C&D waste: (1) WM regulations, (2) waste management system (WMS), (3) awareness of C&D WM, (4) low-waste building technologies, (5) fewer design changes, (6) research and development in WM, and (7) vocational training in WM. These CSFs can serve as valuable references for stakeholders to develop effective C&D WM strategies. The research also adds to the knowledge on how to reduce adverse environmental impacts caused by construction activities in rapidly developing economies. © 2010 Elsevier B.V. All rights reserved. ; postprint

Big Data has shown great potentials in improving management discretion in many areas. However, its applications in construction waste management (CWM) are still in infant stage. This research aims to investigate the prospects and challenges of big data in CWM, by focusing on Hong Kong where a big dataset is made available recently. This study first conducted a comprehensive literature review of big data to understand its definitions, applications, and general challenges of using big data in various sectors. Next, the data collected from Hong Kong government was analyzed to explore the prospects and challenges of Big Data in CWM. Except for the general challenges, big data in CWM has specific challenges mainly due to the specificity of public sectors implementing schemes of CWM. Possible strategies are raised to deal with the challenges so as to embrace the prospects of big data in CWM and relevant domains. This study not only provides government and other sectors in CWM and relevant domains with a clearer understanding of the prospects and challenges of big data that they are facing and corresponding strategies, but also acts as a driving force to stimulate the adoption and proper utilization of big data in sectors involved in CWM. ; preprint

Topics: - Innovation in construction: theories and best practices (General Themes) ; While heated discussions have been directed towards various innovative procurement systems such as PPP, PFI, and BOT that carry the great expectation to help materialise the projects and deliver value to the society, a procurement system named agent-construction system (ACS or in Chinese Dai Jian Zhi) is being prevailing in China's public procurement. This research aims to examine ACS by relating them to China's particular Political, Economics, Social, Technological, Environmental, and Legal (PESTEL) background. It is found that the ACS is promising in procuring public projects owing to two merits: (a) clearly defined right and responsibilities; and (b) appropriate allocation of resources and risks amongst parties involved. The research is particularly useful when governments worldwide are searching for innovative procurement approaches to help deliver public projects and services. It also sheds light on how to devise an innovative procurement system. A word of caution, nevertheless, is that readers should not follow this "good practice" slavishly. One ought to truly understand the essence of procurement innovation and devise suitable innovative procurement systems in a given PESTEL setting. ; postprint

The waste generation rate (WGR) is usually used as a key performance indicator (KPI) to benchmark construction waste management (CWM) performance, with a view to improving the performance con- tinuously. However, existing researches, for different reasons, only investigated a relatively small amount of construction projects, whose WGRs cannot be confidently accepted as KPIs. This study develops a set of more reliable KPIs/WGRs using an available big dataset on CWM in Hong Kong. By mining the 2,212,026 waste disposal records generated from 5764 projects in two consecutive years of 2011 and 2012, the WGRs/KPIs are revisited and refined. Demolition is found the most wasteful works. New building, and maintenance and renovation (M&R) works individually produce the least waste amount but by accumu- lating all M&R works, their contribution to the total amount of construction waste could be phenomenal. Based on the more reliable WGRs from the big data, CWM performance benchmarks for different cate- gories of projects are set up. A contractor can benchmark its CWM performance against its counterparts or its past performance as 'Good', 'Average', and 'Not-so-good', and thus identify better CWM practices that induce superior performance. Based on the benchmarks, the government may consider setting up a WGR-step toll system to encourage those 'Not-so-good' contractors to perform well in the future, and initiate incentives to the companies conducting 'Good' projects to spur better CWM performance. Overall, the WGRs derived from the big data and more robust analyses provide a very powerful and handy tool for CWM.

Rural infrastructure is of vital importance for agricultural growth, economic development, and poverty alleviation, particularly in developing countries such as China. In line with the implementation of a Coordinated Urban-Rural Development Strategy, infrastructure investment in China has consciously been tilted to rural areas. An urgent need exists to assess whether the investment has induced the benefits as expected. Existing research on rural infrastructure investment assessment focuses primarily on economic return while neglecting its social and ecological benefits. This paper identifies a set of critical assessment indicators (CAIs) that can be used to evaluate the multifaceted benefits of rural infrastructure investment in China. Research data were collected through a questionnaire survey given to three groups of experts, including government officers, professionals, and business practitioners who are working in China's housing and urban-rural development sector. Monte Carlo simulation (MCS) is used to generate additional data to supplement the data set from the questionnaire survey. The fuzzy set theory, which appreciates the fuzziness of data from the questionnaire survey, is used in the selection of CAIs. The CAIs can help the local governments in China to make better decisions in investing in rural infrastructure. These critical indicators can also be generalized to provide valuable references for the investigations of rural infrastructure investment in other developing countries. © 2011 American Society of Civil Engineers. ; postprint

Abstract. Risk-based slope stabilization planning integrates the failure probability and the failure consequence systematically and shows promise for use in the practice. This paper attempts to develop a risk-based methodology for stabilization planning for deteriorating soil cut slopes. First, a framework of risk-based stabilization planning for slopes is proposed. Then the time-dependent reliability of deteriorating slopes is analyzed based on observed performance. Thereafter, the slope failure consequence is assessed in terms of expected numbers of fatality. After obtaining the time-dependent risk of slope failure, the time for slope stabilization is determined according to selected risk criteria. Finally, the effect of slope maintenance on the reliability of slopes is evaluated. Based on the analyses, the annual probability of failure of soil cut slopes would increase exponentially in the early stage of service if no maintenance were implemented. As a slope deteriorates, the risk of slope failure increases with time and may reach an intolerable level at a certain time. The risk of slope failure may also reach an intolerable level due to a change of elements at risk. The derived stabilization time depends on the factors that cause the slopes to deteriorate, consequence of slope failure, selected risk criteria, and vulnerability of the affected population.