The role of conceptualization in the evaluation of sustainable concrete

Abstract

Improvement of the sustainability of concrete materials will be realized through the development of analytical tools that facilitate sustainable design and evaluation. However, these processes may be dependent on how sustainability is conceptualized for concrete. Conceptualization is the means by which sustainability is operationalized by creating a structure that connects a qualitative goal to its quantitative indicators. As there exists no established definition of sustainability for the concrete field, conceptualization is a source of uncertainty in the sustainability evaluation of concrete. This paper explores the role conceptualization plays in the evaluation of concrete material sustainability by analyzing its effects using multicriteria analysis and a sustainability indicator framework to quantify sustainability for concrete materials. Six analytical scenarios are explored using frameworks based on direct loading, the three pillars of sustainability, and the Sustainable Development Goals, together with two aggregation methods. It was found that the most sustainable concrete mix varied by scenario, but one concrete mix combining blast furnace slag and high grade recycled aggregates could be judged as the most sustainable due to its highest mean score and lowest variance across all analytical scenarios, which suggests it as the mix least sensitive to methodological choices on conceptualization and aggregation. Overall, however, the sustainability scores were highly correlated between the different scenarios.