Kloridinträngning

Kloridinträngning refers to the process by which chloride ions penetrate and accumulate within a material. This phenomenon is particularly relevant in the context of reinforced concrete. When chloride ions, often originating from de-icing salts or seawater, reach the steel reinforcement within concrete, they can initiate and accelerate corrosion.

The protective passive layer of iron oxides on the surface of the steel rebar is typically stable in the alkaline environment of concrete. However, chloride ions can disrupt this layer, particularly when their concentration exceeds a certain threshold. This breakdown allows for the electrochemical process of corrosion to begin.

Corrosion of steel reinforcement leads to expansion, which can cause cracking and spalling of the concrete cover. This further exposes the steel to the environment, exacerbating the corrosion process and compromising the structural integrity of the concrete element. Understanding and mitigating kloridinträngning is crucial for ensuring the durability and longevity of concrete structures, especially in aggressive environments. Factors influencing the rate of kloridinträngning include the permeability of the concrete, the presence of cracks, and the external concentration of chloride ions.