Assessment tools for the environmental performance of concrete – European classification systems and a novel approach

Abstract In addition to the technological properties of concrete, ecological requirements will become increasingly important in the production of concrete in the future. In recent years, numerous international assessment and classification systems have been developed to transparently communicate and classify the environmental impact of concrete using quantitative parameters. These systems define corresponding classes or levels based on the specific CO 2 -emissions of concrete. Such systems for measuring and classifying CO 2 -emissions of concrete are becoming increasingly important in the planning, tendering, and execution of future construction projects. It is therefore crucial to provide generally applicable methods and classification systems for the assessment of CO 2 -emissions of concrete. This study compares nine recently developed classification systems for evaluating CO 2 -reduced concrete, describing their specific features, limitations and potential. On this basis, a novel approach was developed that combines the international systems into a single concept for compressive strength classes from C20/25 to C50/60. The proposed approach provides a simple and transparent framework that combines existing European classification systems and can therefore support the future implementation of uniform standardized international CO 2 -classes for concrete. In addition, the current practical availability of such CO 2 -reduced concretes is described in relation to the reduction classes of the individual systems.