Comprehensive damage assessment in concrete affected by different internal swelling reaction (ISR) mechanisms

Recent works propose the use of a comprehensive management tool for assessing concrete damage due to alkali-silica reaction (ASR) based on a series of mechanical and microscopic laboratory test procedures, mainly the Stiffness Damage Test (SDT) and the Damage Rating Index (DRI). However, the use of these procedures for assessing other distress mechanisms other than ASR (i.e. delayed ettringite formation-DEF, freezing and thawing-FT, etc.) has never been performed. This paper presents the assessment of concrete mixtures affected by ASR, DEF and FT (single or coupled), through the use of a multi-level approach (microscopic and mechanical), with the aim of generating a comprehensive management guide for evaluating aging infrastructure. The results show that the ASR proposed approach is suitable for analyzing other distress mechanisms. Moreover, qualitative damage models and quantitative charts linking mechanical responses and microscopic distress features are proposed, which enables an easy comparison among the different damage processes.