Field Investigation of Concrete Blocks with Different ASR Reactive Aggregate Types with and Without Surface Hydrophobic Impregnation

Previous field investigation of concrete blocks with different ASR reactive aggregate types with and without surface hydrophobic silane impregnation in the period 2018–2023 has shown promising results. The aggregate in some of the first series of test is fast reactive as they contain a high amount (5–6 vol %) of porous calcareous opaline flint (silicified limestone). Over a period of more than 5 years, moisture content (RH) has been continuously measured inside the concrete cubes and registered whether the concrete has developed harmful expansions and/or visible cracks. These measurements have now been continued for more than 5.5 years on the exposure field on the Technical University of Denmark (DTU) near Copenhagen, Denmark.