BRE BR164 PDF

The third report on a long-term investigation at Northwick Park and on similar concretes in sulphate solutions at BRE.

Various types of concrete have been recovered after 15 years in a high sulphate soil. The amounts of sulphate entering the concretes have been compared and found to vary from practically nil to 1.5 kg SO3m2 of concrete face. The maximum depth of penetration was about 35mm. Only the partly compacted ordinary Portland cement concretes have shown any loss in compressive strength after 15 years. The use of sulphate-resisting cements resulted in reduced sulphate accumulation in the concrete compared with ordinary Portland cement but in concretes having poor compaction, a hydrostatic head applied to one face, low cement content and high water/cement ratio, sulphate accumulation tended to increase even in the sulphate-resisting cement concretes.