Can Corrosion Be Avoided In Reinforced Concrete?
Yes if:
- Concrete is always dry, then there is no H2O to form rust. Also aggressive agents cannot easily diffuse into dry concrete.
- Concrete is always wet, then there is no oxygen to form rust.
- Cathodic protection is used to convert all the reinforcement into a cathode using a battery.
- A polymeric coating is applied to the concrete member to keep out aggressive agents. These are expensive and not easy to apply and maintain.
- A polymeric coating is applied to the reinforcing bars to protect them from moisture and aggressive agents. This is expensive and there is some debate as to its long- term effectiveness.
- Stainless steel is used in lieu of conventional black bars. This is much more expensive than black bars.
- Use FRP rebars.
As for this question, I have different idea wanted to bring out for further discussion. In my opinion, the reason why corrosion will be occurred in reinforced concrete is mainly because there are some cracks formed or caused by some reason such as dry shrinkage, hydration and so on, then the water or moisture can be very easily penetrated into the concrete through these cracks.
ReplyDeleteSince the cracks are mainly caused by dry shrinkage (which is the water on the surface of concrete is evaporated too quickly ), what if we can let the concrete be in the state of SSD (saturated surface dry) condition then I think all of the further problems will be all solved, am I right?
If there are enough water locked inside the concrete, which means the hydration of concrete will be fulled so its final strength and durability will be increased. And if it can undergo a full hydration process, it means it can bring out enough cement paste to form or bond all the aggregate much tightly and have a better water tightness. Then there is no need to worry about the water or moisture will be penetrated inside and cause corrosion in reinforced concrete, doesn't it make some sense?
yes Jeff Yuan, you are right but if we need to keep concrete in SSD condition we need to keep it either fully dry or fully wet. This is impossible because of our changeable weather conditions. For this we can use any admixtures to the concrete which might prevents dehydration process. Do you think it will works?
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