Electron microscopy of the hydration process скачать в хорошем качестве

Electron microscopy of the hydration process

Concrete is not a dull grey mass. Despite changing raw materials, weather and traffic conditions, achieving that the concrete on the building site has a consistency of honey to flow without segregation, solidifies at the given time, develops the compressive strength required for the structural design, and finally withstands 50-100 years of attack by de-icing salt or liquid manure with the help of a specific porosity, is similar to the work of an alchemist in earlier centuries, described in a unique way in the book of the same title by Paolo Coelho. Responsible for the development of these properties are various crystals [1] in cement, the central ingredient of concrete. As soon as they come into contact with water (usually in a concrete plant), the crystals [2] start to grow and thus determine the properties of the concrete. The study of this growth, in all its facets, provides information on how the development of the properties of concrete can be better understood or even deliberately controlled. It is therefore highly relevant for our company. This video was produced by Dr. Alexander Herb, who in his dissertation [3] succeeded for the first time to observe exactly these crystals during their growth and their partial transformation into other crystals under a special scanning electron microscope and to record this in videography. We have also used photographs of Dr. Herb on other parts of our website, for which we would like to express our gratitude. 1] Called clinker phases, e.g. tricalcium aluminate (3 CaO * Al2O3, or C3A in cement notation) 2] Then called hydrate phases, mainly calcium silicate hydrates (m CaO * SiO2 * n H2O) 3] Dr.-Ing. Alexander Herb (2003). Indirekte Beobachtung des Erstarrens und Erhärtens von Zementleim, Mörtel und Beton mittels Schallwellenausbreitung. Dissertation, University of Stuttgart, Department of Civil and Environmental Engineering.