Sulfate attack testing approaches from concrete to cement paste: A review by RILEM TC 298-EBD

Most existing test methods determine the sulfate resistance of concrete using accelerated methods in the laboratory, on mortar or concrete specimens. However, these accelerated tests often use high sulfate concentrations or require very complicated setups, which may alter the deterioration mechanisms, while still being laborious and time-consuming. Additionally, the need for more sustainable binders and distinctive properties of systems incorporating emerging supplementary cementitious materials (SCMs) may limit the applicability of conventional test methods. In this context, the Working Group 3 of RILEM TC 298-EBD aims to develop simple accelerated test methods on cement pastes for evaluating sulfate resistance, which directly investigate the reactive component of concrete. Working at this scale can provide reliable results in a much shorter time than traditional tests on mortars and concretes, while providing means to assess the impact of different SCMs and binders on the resistance to sulfate attack. This paper presents our first step, a critical literature review on sulfate deterioration testing from the concrete/mortar to the cement paste scale. We present a general introduction to sulfate attack, common test parameters, assessment methods, test setups for paste specimens, a discussion of potential approaches, and concluding remarks. Insights gained from this review will be instrumental in establishing an effective and reliable approach to sulfate deterioration testing on cement paste specimens.