Tests on buried structures
There are various tests that may be carried out on buried structures and structures in contact with the ground. (Note that tests on structures above ground are considered separately.) The selection of the most appropriate tests will depend on the particular structure being considered, the nature of the inspection and the reasons for carried it out. Details of the various tests shown in bold are given under separate headings.
Common tests include determining reinforcement depth and carbonation depth. Cores may be taken to determine the strength of the concrete and the cement content. Less common tests include near-surface strength tests, rebound hammer, ultrasonic pulse velocity and the determination of chloride profiles. Extracted samples will be used for laboratory testing to determine chloride diffusion and for petrographic tests (see separate entry and Concrete Society Technical Report 71, Concrete petrography: An introductory guide for the non-specialist). Soil and groundwater analysis may also be required.
Infrequently tests include expansion cores, porosity, water absorption, gas and water diffusion, initial surface absorption, thermography, radar and gamma radiography.