What concrete deficiency is caused by corroded rebar or severe overstress and cannot be visually identified?

What concrete deficiency is caused by corroded rebar or severe overstress and cannot be visually identified?

• A. Delamination
• B. Cracking
• C. Spalling
• D. Scaling

Answer: (A)

Internal separation within the concrete that isn’t visible on the surface is what this item targets. When reinforcing steel corrodes or the member is subjected to severe overstress, forces build up inside the concrete and can cause delamination—layers of concrete to pull apart parallel to the surface. That kind of damage stays hidden beneath the outer skin and may not show obvious cracks or chunks missing yet, so you can’t rely on visual inspection alone. Delamination is different from cracking, spalling, or scaling, which typically manifest as visible surface changes. Cracking shows up as cracks on the surface, spalling as pieces of concrete breaking away, and scaling as flaking of the top layer. Because delamination is internal, it requires nondestructive testing or exposing the surface to confirm, such as hammer sounding, radar, or infrared methods. So the best answer is delamination because it describes hidden interior damage caused by corrosion or overstress that isn’t identifiable by sight alone.

Internal separation within the concrete that isn’t visible on the surface is what this item targets. When reinforcing steel corrodes or the member is subjected to severe overstress, forces build up inside the concrete and can cause delamination—layers of concrete to pull apart parallel to the surface. That kind of damage stays hidden beneath the outer skin and may not show obvious cracks or chunks missing yet, so you can’t rely on visual inspection alone.

Delamination is different from cracking, spalling, or scaling, which typically manifest as visible surface changes. Cracking shows up as cracks on the surface, spalling as pieces of concrete breaking away, and scaling as flaking of the top layer. Because delamination is internal, it requires nondestructive testing or exposing the surface to confirm, such as hammer sounding, radar, or infrared methods.

So the best answer is delamination because it describes hidden interior damage caused by corrosion or overstress that isn’t identifiable by sight alone.