| Abstract: | No Crucial Water Vapour Penetration through Constructions, made of Concrete of High Resistance against Water Penetration Concrete constructions in groundwater in accordance with the WU‐guideline are not allowed to show wetness on the inside. A high‐quality using of such underground‐concrete‐constructions requires additionally a limitation of the penetrated water vapour. The investigations of the authors had shown that it does not come to any agglomeration of humidity behind a coating on the inner surface of a concrete‐construction in groundwater under the following conditions: crack‐free concrete, water pressure up to 5 bar, w/z ≤0.6, h ≥20 cm and not too dry concrete. Thus there is no threat of osmosis damage. The presented humidity profiles in drill cores, taken of constructions, which are in touch with groundwater since decades, confirm this: There is neither with nor without an interior coating any humidity concentration in the internal half of the groundwater‐ affected base plates detectable. This on the condition that the concrete is of high resistance against water penetration. In the presented new laboratory tests the penetration of watervapour through concrete cylinders, obeying the aforementioned concrete quality conditions, is measured for water pressure on one side: With 5 bar water pressure only a small range of water vapour penetrates, under atmospheric pressure (foot bath) there is no water vapour penetration registrated. |
