Visual Defects of Concrete: one of the simplest ways to understand what exactly causes concrete to fail would be performing a Visual Survey of the deteriorated concrete structure. When a client hires an Engineer to inspect a concrete structure, it is most likely because the owner visually noted some form of deterioration. This, technically, may be considered a preliminary visual test.
There are many different tests that are done to analyze a deteriorated structure. Usually, the first test an Engineer (or Inspector) will conduct is a Visual Condition Survey so as to get a sense of where, if any, additional testing should take place. This survey usually consists of the Engineer walking the site looking for any signs of deterioration that can be noticed visually and then noting them. The Engineer makes notes of both serious and non-serious defects to the concrete structure.
In some cases, in view of the findings from the Engineer, the amount of work required to repair the structure may be determined. The more serious modes of deterioration that are found visually usually lead to further expensive investigation and repair.
When the visual test is conducted by the engineer during the Condition Survey it is for the purpose of analyzing the visually noticeable deterioration in the concrete structure.