Assessment of the efficiency of distinct surface treatments to mitigate ASR-induced development

Over the years, various coating materials have been used to mitigate/rehabilitate concrete once alkali-silica reaction (ASR) takes place. Although promising results are demonstrated, their efficiency is compromised by the progression of ASR and crack formation. Recently, new coatings with higher penetrability and enhanced self-healing properties have shown good performance against distinct durability problems in concrete, yet their behaviour under ASR development is unknown. This research appraises the ability of hydrophilic self-healing coating (CA) mixtures to mitigate concrete deterioration caused by ASR in its initial, moderate and advanced phases. Their efficiency is multi-level assessed, and comparisons with other systems (e.g., silane/siloxane, rigid-coating and lithium-based) are also performed. Results indicate that the surface treatments with CA changed ASR kinetics while not altering the ASR mechanism of deterioration. Finally, qualitative charts are provided to help select different types of surface treatments and the most appropriate “timing” for their application. • Coating and sealers treatments modified ASR kinetics. • Although changing ASR kinetics, the surface treatments did not change the deterioration mechanism. • Coating with crystalline waterproofing and water repellent showed higher efficiency in lowering ASR. • Coatings containing enhanced self-healing properties sealed cracks with a maximum 7 mm depth. • The qualitative charts can help decide the most appropriate time to apply different treatments.