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HOW TO INCREASE DURABILITY OF CONCRETE PILES

DURABILITY OF CONCRETE PILES Properly mixed concrete compacted to a dense impermeable mass is one of the most permanent of all constructional material and give little cause of concern about its long-term durability in a non aggressive environment. However, concrete can be  attacked by sulphate and sulfuric acid  occurring naturally in soils, by corrosive chemicals which may be present in industrial waste in fill materials and by organic acids and carbon dioxide present in ground water as a result of decaying vegetable matters. Attack by sulphates is a disruptive process whereas the action of organic acids or dissolved carbon dioxide is one of leaching. Attack by sulphuric acid combines features of both processes. The severity of attack by soluble sulphates must be assessed by determining the soluble sulphate content and the proportions of the various cat ions present in an aqueous extract of the soil. These determinations must be made in all cases where the concentration of s...