Sulphates in solution in contact with concrete can cause chemical changes to the cement, which can cause significant microstructural effects leading to the weakening of the cement binder.
Environmental conditions such as those met in sulphate-rich soils and some natural waters require concrete to be designed to resist deterioration due to sulphate attack.
High sulphate concentrations in water are normally either naturally occurring or as a result of industrial effluents. High sulphate concentrations are also found in seawater. With proper consideration at the design stage Holcim will be able to incorporate their considerable knowledge and incorporate sulphate resisting characteristics into the concrete.
Component materials can be effectively used to produce highly durable concretes that will perform well in sulphate rich environments. Alternatively, areas where sulphate levels are excessive can be identified on projects highlighting the need for further design.