Societal Burden and Engineering Challenges of Ageing Infrastructure

Ageing is an inherent feature of nature and, hence, of materials, structures and systems. Yet, it seems a rather new topic in both science and engineering. The main reason for increasing attention for ageing as a topic is the growing awareness that, particularly in industrialized countries, ageing of our assets is a financial burden for the society. It touches our environment and a country's economy. It affects the overall sustainability of our planet and deserves, therefore, our utmost attention. In this contribution the urgency and challenges of ageing of concrete structures are addressed. Recent estimates of the extent of the issue and how ageing problems are dealt with in different disciplines, reactive or pro-active, are mentioned. The complexity of ageing problems will be evaluated by looking in more detail to the evolution in concrete mix design and the consequences thereof for the long-term performance of concrete structures. In this evaluation different kinds of driving forces contributing to ageing will be identified. Emphasis will be on ageing of concrete infrastructure and the need of research on ageing phenomena will be addressed.