No abstract

White roof (WR) and Sedum lineare tray garden roof (STGR) have been convinced to improve the energy-efficiency and provide various benefits for conventional impervious grey roofs. Some national and local standards have standardized and recommended these technologies in existing building retrofits, however, they do not include assessment and choice of a particular roof 8 retrofit in different climates. This paper presents a 40-year life-cycle cost analysis (LCCA) of an 9 office building roof retrofitted by adding either WR or STGR over an existing grey roof in five cities, 10 located in four Chinese climate zones. The LCCA find that the WR retrofits exhibit positive life-11 cycle net savings (NS) in warm winter zones, ranging 5.7-35.1 CNY/m 2 , and STGR retrofits have negative NS of -81.3--16.7 CNY/m 2 in all climate zones. The NS of both WR and STGR generally tend to improve as one moves from the coldest cities to the warmest cities.LCCA results suggest that adding new building codes concerning crediting or prescribing WR and STGR retrofits into office buildings with grey roofs in hot summer climate zones and warm winter zone in China, respectively. And featured by more specific requirements, the localized Technical Norms help promote the implementation of new building codes.

Multiple policies have been formulated to promote the development of prefabricated building (PB). However, ineffective policies increase the financial burden of the governments and hinder PB development. This study aims to identify effective policies and develop a practical policy framework to encourage developers to implement PB. Text analysis is to identify the policies related to PBs from the numerous samples. A survey is to verify the effective policies and explore their effects on the developers’ willingness to implement PBs. The findings suggest that the current policy system of PBs is complete but uneven, focusing on environmental policies. The most cost-effective tools are land limitations, tax incentives, and financial support. Besides, policies are interrelated in affecting developers’ willingness to implement PBs. It provides a reference for policy evaluation in application scenarios, which expands the literature research on the policy. Meanwhile, it provides a guide for policymakers to evaluate the effectiveness of policies and formulate practical policy frameworks to promote PB development.

It is imperative to strengthen the high-risk work system assessment and accidents prevention and control of hydropower construction hazards based on the identification of risk factors. Work system safety is a function of many factors, besides it is dynamic and complex. There may be relations and dependencies among the safety factors. Therefore, work system safety should be analyzed in a holistic manner. In this study, the accidents data analysis is used to identify the links among the factors, which are used as factor dominance relation in Analytic Network Process. Therefore, the influence factors of engineering construction safety are worthy of studying. Through extensive reading literature and information, making contrast and analyzing, researching and other methods, finishing the preliminary indicators of construction safety influencing factors, after conducting questionnaire survey, ultimately identified 19 indicators of factors and based on these indicators draw SEM model by AMOS software. With the influencing factors, it gives assessment result through the variable assignment and the factors weight derived from SEM and ANP method.

Work system safety is a function of many factors, besides it is dynamic and complex. There may be relations and dependencies among the safety factors. Therefore, work system safety should be analyzed in a holistic manner. In this study, the accidents data analysis is used to identify the links among the factors; the relationship analysis of the independence between the behavioral factors has been performed in order to find the non-independent factors. Among the Human Factors Analysis and Classification System (HFACS), the impact of the high-level factors on the bottom level is determined. After a period of monitoring and rectification, it implements a new round of safety monitoring and factors comparison and interaction analysis, so to achieve the goal of “the nature of safety” of hydropower projects construction.