In early 2020, Infrastruct was requested to carry out in-situ permeability testing on underground reinforced concrete tanks for a large and well-known Irish manufacturing Company. The testing on the concrete tanks was required to assess, non-destructively, the in-situ quality of the concrete and its resistance to water penetration prior to entering service for the Company.

The permeability of concrete to liquids has major implications for the durability of the concrete during its service life and on its ability to retain the liquid within the tank structure. While there is no one standard test method recommended, Infrastruct uses the Germann Instruments GWT test system for the on-site assessment of water permeability.

The GWT system can be used for:

1. Evaluation of the water permeation of the skin-concrete in finished concrete structures.
2. Testing the water tightness of construction joints and sealed control joints.
3. Testing the concrete surface before and after the application of a protective water-proof coating to assess the effectiveness of the coating and its application.
4. Evaluation of the water permeation properties of masonry structures.

Photographs 1 and 2 below show the GWT test system on the reinforced concrete walls of the underground reinforced concrete tank. Note the marked-up location of the embedded reinforcement within the walls, it is recommended to avoid testing over the reinforcement.

The results of the GWT testing was recorded on-site by our Engineers and a comprehensive report, with interpretation, was prepared for our Client.

For more information on GWT testing or any structural testing and investigations, please contact Dr Thomas Callanan in Infrastruct Asset Management Services Limited.