What is a disadvantage to using reinforced concrete pipe?

• A. It is very lightweight
• B. It cannot be used in cold climates
• C. It does not require any protection in the ground
• D. Needs special protection in high-chloride soils

Answer: (D)

The main idea here is durability in aggressive soils. Reinforced concrete pipe relies on steel reinforcement embedded in concrete for strength, but chloride ions in soils or groundwater can attack that steel. If the concrete cover isn’t enough or the concrete is too permeable, chlorides reach the reinforcement and cause corrosion, leading to cracking, spalling, and reduced structural capacity. To prevent this in high-chloride soils, extra protection is needed—such as greater concrete cover, higher-quality low-permeability concrete, epoxy-coated or otherwise corrosion-resistant reinforcement, or protective linings. That makes special protection in high-chloride soils a real disadvantage for reinforced concrete pipe.