The location of temporary facilities in a construction project and the entire site layout plan directly affect project objectives such as time, labor cost, and material transportation and handling. The layout of construction sites also affects entrainment factors such as energy consumption, carbon footprints, and overall construction operation productivity. While site layout planning has been intensively investigated from a project objectives perspective, there have been very few studies of energy-efficiency-based planning, or of the sustainability performance of site layouts. This study developed a green performance evaluation system aimed at improving the sustainability of construction site layouts. The identified factors include six sustainable evaluation categories covering energy conservation and environmental protection, people-oriented principles, construction efficiency, intensity of economic growth, intensity of space use, and the overall control of process. An analytic hierarchy process (AHP) was adopted to determine the weight of each attribute and a fuzzy comprehensive evaluation method was established to carry out the evaluation. The 23 attributes adopted in this paper were identified in the literature; however, the major contribution of this paper is the development of a green performance evaluation system. This system integrates both qualitative and quantitative attributes and provides an overall evaluation of the environmental effectiveness of a construction site layout. The proposed evaluation system was validated with a commercial building project. The average utilization ratio of the case study site was calculated as 94%, and lessons learned are discussed in this paper. The case study analysis identified available site spaces around the building and examined how the arrangement of resources and facilities ensures effective connection between construction activities. The findings showed that the facility’s layout plays a crucial role in energy consumption and green performance. The proposed system will support construction project managers to create high-performance construction site layouts in more scientific and systematic ways.

Mobile construction machineries are accident-prone on a dynamic construction site, as the site environment is constantly changing and continuous safety monitoring by human beings is impossible. These accidents usually happen in the form of machinery overturning or collapsing into risk areas, including the foundation pit, slopes, or soft soil area. Therefore, preventing mobile construction machineries from entering risk areas is the key. However, currently, there is a lack of practical safety management techniques to achieve this. Utilizing a wireless sensor device to collect the location information of mobile construction machineries, this research develops a safety warning algorithm to prevent the machineries moving into risk area and reduces onsite overturning or collapsing accidents. A modified axis aligned bounding box method is proposed according to the movement patterns of mobile construction machineries, and the warning algorithm is developed based on the onsite safety management regulations. The algorithm is validated in a real case simulation when machinery enters the warning zone. The simulation results showed that the overall algorithm combining the location sensing technology and the modified bounding box method could detect risk and give warnings in a timely manner. This algorithm can be implemented for the safety monitoring of mobile construction machineries in daily onsite management.

Age-friendly communities (AFCs) are an important measure for fostering active aging. The key to achieving an age-friendly living environment is to construct or renovate it according to the residents’ demands. To date, very few studies have attempted to delve into the AFCs’ environmental demand from different groups’ perspectives. Based on the theory of place attachment, the aim of this paper is to explore the demand diversity of different groups for the AFC environment. This study employs the nonparametric test and the Ordinal Priority Approach (OPA) to investigate the demands from the residents’ perspectives, and is enhanced by incorporating experts’ opinions. The empirical analysis shows that residents have a high level of demand for the physical environment (indoor and outdoor) and social environment (community services and social participation). At the same time, experts advocate the importance of using digital technologies to support people aged 45–65 who have higher requirements for a community environment than older adults. The findings also show that other backgrounds, such as gender, living arrangements, and year of the community establishment, lead to different demands. However, the impact of residents’ education level, occupation, income, and self-care ability on the environmental demands is low. Based on the research findings, the paper provides some practical suggestions for the future design and development of AFCs.

The purpose of this paper is to explore and simulate the barriers of transaction costs to public rental housing (PRH) exits in China. The two-period model of household consumption utility, with the constraints of transaction costs, is employed to conduct our analysis. The overall results show that if transaction costs go beyond the tenants’ ability to afford them, the tenants will continue to live in the current PRH units, resulting in an obstruction of PRH exits. When the rent ratio in the two periods is higher than 1 and continues to rise, a higher proportion of transaction costs for household consumption contributes to a greater impeding effect, so the barriers’ effect with regards to concurrent changes in rent and income is similar to that of changes only in rent. We observe a close relationship between the acceptable maximum transaction costs and the variety of housing rents. If the tenants cannot afford the maximum transaction cost or housing rent in the private market, they will stop searching for a more advantageous housing and will prefer living in the current PRH units. Moreover, the proportion of maximum acceptable transaction costs does not vary with the changes in the expected household income; income growth only increases the absolute value of transaction costs, not the relative one. Therefore, the government should not only provide housing search services to help tenants leave the public rental sector, but should also adjust the supply of affordable housing for households with housing stress.