Technical survey methods
The visual inspection of construction materials, especially concrete, is insufficient to detect deterioration within the material, therefore other methods of investigation must be used to supplement the visual examination.
Methods and techniques for diagnosing construction conditions are divided into the following categories:
The above techniques are further categorized into a variety of related techniques that determine damage and deterioration of the structure, the properties of its materials, and its geometric elements.
Tests and trials can be conducted on-site or off-site in a specialist laboratory. In the case of laboratory testing, it will be necessary to take samples of the structure on-site, performing the so-called core sampling.
Tests and essays can also be classified according to their impact on the structure. The types of tests to be conducted can be classified into direct (destructive) and indirect (non-destructive), the latter affecting the structure, and the former is not.
Direct and indirect identification techniques are used to assess the existing condition of the construction materials, identify deterioration and damage, and map geometric features.
A variety of non-destructive (indirect) diagnostic tests and techniques can be performed on-site without affecting the structure. The following are among the more common ones:
The application of semi-destructive (direct) diagnostic tests and techniques requires the removal of small pieces from the load-bearing elements of the structure. They are done in the laboratory.
The most common semi-destructive diagnostic tests are the ones that follow:
The type of test to be conducted will depend on various factors such as the type of elements that compose the structure, the extent of the damage, the intended scope of the intervention, etc. Moreover, the type of method to be applied may depend on the structure’s historical and architectural significance.
