Chloride Absorption Behavior of Layered Double Hydroxides in Chloride Environment

Chloride penetration is an important factor of concrete durability, whereas chloride ions have the potential to be absorbed by layered double hydroxides (LDHs). Magnesium-aluminum-CO3 LDHs are used in this experiment, and chloride ion absorption in chloride solution and hardened cement paste is studied. Additionally, the chloride penetration behavior in concrete containing raw LDHs and calcined LDHs (CLDHs) is also studied. The results indicate that raw LDHs show lower chloride ion absorption ability and CLDHs can absorb chloride ions in cement paste to reconstruct the structure and reduce the chloride concentration. The addition of CLDHs absorbs the chloride ions in concrete to delay the penetration, which improves the chloride ion resistance of concrete.