A design approach for sustainable bridges – Part 1: Methodology

Sustainability is a holistic concept that is becoming increasingly important in the construction sector. However, the implementation of sustainable concerns in daily practice faces several barriers, such as the lack of practical approaches to make it feasible. To overcome this problem, a life-cycle approach, integrating environmental, economic and social criteria, was developed, focusing on motorway bridges. The approach has two major perspectives: (a) an accounting perspective, and (b) a decision-making perspective. This paper presents a detailed description of the proposed methodology. It enables the design of bridges from a sustainability-based perspective. It results in an increased perception of the major problems in the life cycle of bridges and thus contributes to an improved design and lifetime behaviour, fostering the sustainability of this sector of the infrastructure. The application of the approach to two case studies is presented in a companion paper (Part 2).