Ecological Impact and Economic Aspects of Advanced Concrete Technologies

Reinforced concrete structures are often conceived for a certain time span of serviceability. Due to the superposition of different kinds of loads and particularly due to the presence of aggressive substances the resistance of construction materials is insufficient in numerous cases. Hence, many structures have to be repaired before the end of their designed life span. In case of reinforced concrete structures these repair measures are not only very expensive but they also consume high amounts of energy and materials which causes strong environmental impacts. The main challenge in developing reliable concrete technologies is the capability to enhance the life span of new and already repaired structures to a reasonable maximum. When aiming this objective not only durability related material properties have to be accomplished but their environmental impact has to be minimized simultaneously. This paper evaluates different concrete technologies and materials from diverse perspectives: Durability (simulating expected life span using numerical analyses), ecology (product life cycle and environmental impact assessments) and economy (estimating life cycle costs by investment appraisals). This kind of combined analysis facilitates the efficient design of structural elements and repair measures and provides the possibility to significantly increase the life span of new and repaired concrete structures.