Nicholls Colton Concrete sampling

Sampling of Hardened Concrete

Concrete Sampling allows us to assess the susceptibility of reinforced concrete to corrosion.  Some chemicals were present in the concrete mix during construction; whereas others may diffuse into the concrete from external sources.  To determine the current chemical composition of concrete, samples may be taken and subjected to laboratory testing.  Whereas core and lump samples of concrete can be crushed in the laboratory, common practice is for dust samples to be taken on site by percussion drilling methods.  Holes of a specified diameter are drilled to a predetermined depth, with the concrete dust obtained being saved in sealed pots for subsequent testing.

When considering corrosion risk, testing to concrete dust samples is most commonly undertaken for chloride ion contamination.  During such sampling, concrete to beyond the depth of reinforcement is sampled, frequently in three or four incremental depths to allow a profile of chloride contamination against depth to be obtained.

Details of sample location and depth are kept in a site register for future reference.

Such concrete sampling is undertaken to a documented in-house method covered by our *UKAS accreditation.