Minimisation of Water Content in Concrete

Abstract:

In the production of structures made of concrete it is sometimes required to make a completed structure contain a minimum amount of free water. From the point of view of effectiveness of the production process it is also preferred to dry the concrete in a short time and at a reasonable cost. Required for free water content can be limited by various factors (e.g. construction covered by flooring sensitive to humidity, frost resistance, etc.).The moisture characteristic of concrete is verified in civil engineering provided that the concrete is located in the environment with normal atmospheric pressure. By solving the project “Development of methods for structure of thermal vacuum insulated containers” we have met a requirement to produce concrete with extremely low moisture content. It was found out that information about moisture content of concrete obtained by currently used method was unsatisfactory for concrete in the environment with extremely low atmospheric pressure. The research has indicated that usual methods of concrete drying are not sufficient for concrete subjected to vacuum because they don´t eliminate physically bound water.

• Periodical: Key Engineering Materials (Volume 691)
• Pages: 230-238
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.691.230
• Online since: May 2016
• Authors: Ivan Juríček*, Ľudovít Fillo
• Keywords: Chemically Bound Water, Drying of Concrete, Effect of Vacuum on Concrete, Free Water, Measure of the Moisture Content of Concrete, Physically Bound Water

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