Performance of concrete in XS1, XS2 and XS3 environments

An extensive chloride-profiling programme was undertaken over an eight-year period on nine concrete pier-stems placed at a marine location to represent XS1, XS2 and XS3 environmental exposure conditions as defined in European Standard EN 206-1. The pier-stems were 2-0 m high and octagonal in plan with each vertical face 0-66 m wide and were constructed in groups of three (one each placed at the locations defined above): one group, which was used as a benchmark, represented plain Portland cement concrete; the second group had a waterproofing agent (Caltite) added at the time of mixing; and the third was treated with silane. Chloride concentration profiles were taken at a number of locations on each pier-stem, which were subsequently used to evaluate the temporal change in effective diffusion coefficient and surface chloride concentration for the different exposure conditions. In addition, it allowed assessment of the relative performance of the plain concrete, Caltite concrete and silaned concrete pier-stems with regard to chloride ingress.