Geotherm recommend that thermal resistivity quality control checks be carried out on materials used for bedding/backfilling of the cables/conduits.
We recommend that the backfill material be sampled and tested at regular intervals during the installation process to ensure specified materials have not been substituted and the performance specifics are reached.
Geotherm have a range of sampling techniques to collect backfill material in preparation for quality control testing.
Bedding samples would be collected from site, and allowed to cure (where concrete stabilised). The samples would then be transported to Geotherm’s Laboratory, and subjected to thermal resistivity testing in the fully dried out state.
Sand type backfill would be prepared in our laboratory to the density as achieved during installation in preparation for testing.