Water

Water is seldom 'just water'. It nearly always contains other substances to some degree such as calcium, humus, aluminium and nitrates. The quality of water is important not only for drinking, but also as a constituent in building materials. For example, water with a high humus content produces bad concrete, since humus acids corrode the concrete.

The terms 'hard' and 'soft' waterare well known. Hard water contains larger amounts of calcium and magnesium, typically 180-300 mg/l, than soft water, which contains approximately 40-80 mg/l. Very soft water will have a dissolving effect on concrete.

Water also has different levels of acidity which is expressed in the pH-scale with values from 0 to 14. The lower the pH value, the more acidic the water. A pH value of 6.5-5.5 has a slightly aggressive effect on concrete and materials containing lime, whilst a pH value under 4.5 is very aggressive. Marsh water contains large amounts of sulphuric acid and is therefore unsuitable for most uses. Free carbonic acid, found in most water, attacks lime and corrodes iron. Sulphates in water, especially magnesium sulphate in salt water, are also corrosive and attack lime products.

IMPROVING COLLOIDAL PROPERTIES

Energized water (E-water) is water that has been treated in a levitation machine. The machine is a hyperbolic cylinder where the water is spun in a powerful and accelerated spiral movement. The process was developed by Wilfred Hacheney in Germany in 1976. When this water is used in cement, it has been found that the material assumes an amorphous mineral structure as opposed to ordinary crystalline concrete. This is probably due to increased colloidal properties, i.e. reduced tension in the water that increases contact between the water and the concrete particles. The practical consequences are better compressive and tensile strength and a higher chemical stability, including against air pollution. According to research the level of tolerance can drop to pH2, and at the same time the proportion of water and the setting time can be reduced. More conventional ways of increasing the colloidal properties usually entail mixing in small quantities of waterglass, natron and/or soda.

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