Development of UHPC mixtures from an ecological point of view

Reinforced Concrete (RC) is the predominant and most frequently used building material with a worldwide annual material flow of approximately 20-25 billion tons. Consequently, cement as the most used inorganic binding material is responsible for more than 5% of the total anthropogenic CO2 emissions. Ultra High Performance Concrete (UHPC) is an emerging high-tech building material that - in comparison to normal strength concrete (NSC) - allows for more slenderness and increased durability when designing RC-structures. The ecological impact of UHPC is affected by the high cement content with more than double the amount needed in comparison to normal strength concrete. Substitution of cement in the mixture by less-energy-intensive hydraulic concrete additives is investigated regarding its influence on the concrete properties and its environmental impact parameters calculated for the different UHPC mixtures.