Chapter 3: Materials and Circularity

This chapter outlines the fundamentals of circularity, raw materials and waste, lifecycle flow analysis, recycling and how we can measure circularity. It outlines a circularity assessment for the key structural materials we use in bridges, noting which are good, and not so good. The materials considered are traditional materials such as rocks & aggregates, bricks and timber; current materials such as cement & concrete, iron & steel, and aluminium; and modern materials like fibre reinforced plastic. The materials are considered at a global scale to show their overall circularity, and effect on this planet. In this analysis the data is derived from sources with material mass flows. None of the bulk materials considered in the analysis are currently circular. The chapter considers the material intensity of bridges and uses examples to outline the estimation of circularity for bridges. This chapter will assist bridge professionals in addressing the United Nations sustainability goal 12: Responsible consumption and production.