Foundations

The largest volumes of concrete in a typical project usually are either below or at ground level and therefore can be placed by methods different from those employed on the superstructure. Concrete work below ground can vary enormously – from filling large diameter bored piles or massive mat foundations to the intricate work involved in basement and sub-basement walls.

Concrete must be moved from the mixer to the point of placement as rapidly as possible without segmentation or loss of ingredients. The transporting and handling equipment must have the capacity to move sufficient  concrete so that cold joints are eliminated .

However, it is important to waterproof the foundation to protect the reinforcements and concrete against attack by sulphates such as calcium sulphate, sodium sulphate and magnesium sulphate. Calcium hydroxide and chloride ion can also attack the concrete and reinforcements as well as high water table.