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A customized program on concrete technology for the construction industry in Hong Kong is based on the ISO 9000 quality management system. More than 269 students have been trained; 48.7% of enrollment comes from concrete suppliers. (SK)

Construction delays are common in civil engineering projects in Hong Kong, inevitably resulting in contractual claims and increased project cost. This study was aimed, first, at gathering the perceptions of civil construction practitioners on how significant are the causes of delay; and, second, investigating whether the suggestions as stated in the report of the Construction Industry Review Committee (the Committee comprises members with good standing and knowledge in the construction and related fields as well as those from other professions who are responsible for examining the current state of the construction industry in terms of its output quantity, the quality of work, its environmental friendliness, site safety, its workforce and the system of supervision) are applicable to and effective at mitigating the corresponding delays with reference to a ranking order established using the mean score method. The extent of the differences in perception among the different respondent groups on these two issues was also examined using the rank agreement factor (RAF), percentage agreement (PA), and percentage disagreement (PD). The differences in the perceptions of the respondents on the significance of delays and the actual causes of delays for the six projects studied were also examined. The results of the study showed that the respondents tended to admit their own faults as shown in the top ten significant causes of delay. A strong consensus was found between the client and consultant groups on the significance of the various causes of delay (PA=74%) and the effectiveness of mitigation measures (PA=67%) compared with the other pairs of groups. The consultant and contractor groups held extremely different perceptions regarding the significance of various delay causes (RAF=4.9 and PD=32%) and the effectiveness of corresponding mitigation measures (RAF=6.2 and PD=47%). It is believed that the findings can provide much more insight for the construction practitioners as well as the researchers and thus help to improve the productivity and overall performance of civil construction projects in Hong Kong. DOI:10.1061/(ASCE)0733-9364(2006)132:6(636) CE Database subject headings: Construction; Productivity; Performance characteristics; Project management; Hong Kong; Delay time.

Abstract: Since the safety professionals are the key decision makers dealing with project safety and risk assessment in the construction industry, their perceptions of safety risk would directly affect the reliability of risk assessment. The safety professionals generally tend to heavily rely on their own past experiences to make subjective decisions on risk assessment without systematic decision making. Indeed, understanding of the underlying principles of risk assessment is significant. In this study, the qualitative analysis on the safety professionals’ beliefs of risk assessment and their perceptions towards risk assessment, including their recognitions of possible accident causes, the degree of differentiations on their perceptions of risk levels of different trades of works, recognitions of the occurrence of different types of accidents, and their inter-relationships with safety performance in terms of accident rates will be explored in the Stage 1. At the second stage, the deficiencies of the current general practice for risk assessment can be sorted out firstly. Based on the findings from Stage 1 and the historical accident data from 15 large-scaled construction projects in 3-year average, a risk evaluation model prioritizing the risk levels of different trades of works and which cause different types of site accident due to various accident causes will be developed quantitatively. With the suggested systematic accident recording techniques, this model can be implemented in the construction industry at both project level and organizational level. The model (Q 2 REM) not only act as a useful supplementary guideline of risk assessment for the construction safety professionals, but also assists them to pinpoint the potential risks on site for the construction workers under respective trades of works through safety trainings and education. It, in turn, arouses their awareness on safety risk. As the Q 2 REM can clearly show the potential accident causes leading to different types of accident by trade of works, it helps the concerned safety professionals and parties to plan effective accident prevention measures with reference to the priority of the risk levels. [Copyright &y& Elsevier]

Phase change material (PCM) is a kind of thermal energy storage material. Solid-liquid PCM composite materials must overcome the issues of material leakage and low thermal conductivity before they are suitable for widespread use in the fields of building and industry. In this study, porous expanded graphite (EG) is used as a carrier, which absorbs the PCM to fabricate EG/paraffin composites (EG/P) containing 90.6% paraffin, and a latent heat of up to 105.3 J/g was measured. Because gypsum board is widely used in buildings, therefore, EG/P composites are suitable to be integrated into gypsum to develop expanded graphite/paraffin gypsum-based composite material (EGPG) for thermal energy storage. In order to optimize the performance of EGPG, carbon fiber (CF) is used to reinforce their thermal and mechanical properties. The test results show that when 1 wt % CF is incorporated into the EGPG, the thermal conductivity increased 36.0%, and thus EGPG shows superior thermal control through the significantly increased efficiency of heat transfer. After 1 wt % CF was added, the flexural and compressive strength of EGPG were increased by 65.6% and 6.4%, respectively. The improved thermal and mechanical performance of EGPG modified by CF demonstrates that it is a structural-functional integrated building material suitable for building envelope system. [ABSTRACT FROM AUTHOR]