Comparative Sustainability Assessment of Proprietary and Non-Proprietary Ultra-High Performance Concrete Mixtures

Abstract

Ultra-high-performance concrete (UHPC) has greater strength and durability compared to traditional concrete. While these benefits are well established, there are differences in UHPC based on the constituent materials in the mixture. These variations impact the mixtures’ CO2 emissions, efficiency, and cost. Given the contribution of concrete to overall greenhouse gas emissions, it is important to understand the potential impact of UHPC from an environmental standpoint. This study addresses the environmental and economic impact of UHPC by examining five proprietary and five non-proprietary mixtures. The investigation is guided by three research questions, as follows: (1) How do energy consumption, CO2 emissions, and cost compare between proprietary and non-proprietary UHPC mixtures? (2) Which materials are the most influential drivers of these sustainability metrics? (3) Can non-proprietary mixtures provide comparable or better performance in terms of sustainability? Using secondary data from the literature, we calculate and analyze the energy, emissions, and cost of each UHPC constituent. The results indicate that steel fibers account for 53% of the total energy of UHPC. Ordinary Portland cement (OPC) is responsible for 73% of total CO2 emissions. Aggregates, admixtures, and SCMs have a minimal impact on the energy and emissions of the selected mixtures. However, they can affect the cost significantly. To highlight the key findings, non-proprietary mixtures showed substantial sustainability advantages. For example, UHPC-1 achieved up to 65% lower energy consumption, 49% lower CO2 emissions, and 80% lower cost compared to proprietary mixtures. These results highlight the potential of non-proprietary UHPC to serve as an ecologically friendly and cost-effective substitute for infrastructure applications.