Estimated lifetimes of road pavements in Sweden using time-to-event analysis

Maintenance planning of road pavement requires reliable estimates of roads’ lifetimes. In determining the lifetime of a road, this study combines maintenance activities and road condition measurements. The scope of the paper is to estimate lifetimes of road pavements in Sweden with time to event analysis. The model used includes effects of pavement type, road type, bearing capacity, road width, speed limit, stone size and climate zone, where the model is stratified according to traffic load. Among the nine analyzed pavement types, stone mastic had the longest expected lifetime, 32 percent longer than asphalt concrete. Among road types, ordinary roads with cable barriers had 30 percent shorter lifetime than ordinary roads. Increased speed lowered the lifetime, while increased stone size (up to 20 mm) and increased road width lengthened the lifetime. The results are of importance for life cycle cost analysis and road management.

Making Energy Interventions more Effective : Situation, Interaction, and Precondition

A main purpose of this paper is to propose to policy makers, building professionals, and other non-social scientists a way to make energy interventions more culturally informed and, thereby, more effective. The case study on house purchasers gives an ample illustration of the richer results that can be achieved by paying attention to three aspects of energy efficiency initiatives: the contexts and situations of choice in each particular case, the interaction among relevant social actors, and the culture-specific preconditions for choice. Research on how purchasers of new pre-fabricated houses in Sweden choose their heating system show how such decisions tend to fall between two stools. Furthermore, the organizational structure of housing companies frames house purchasers' decision making. An important result is that energy saving or conversion measures must be promoted at an early stage amongst those who plan and construct buildings (rather than later amongst dwellers and energy end users).