Corrosion is to iron what kryptonite is to Superman. It makes the iron weak and prone to damage and failure. Concrete constructions are also not completely safe from corrosion. In fact, around 40% of all concrete structures fail because of corrosion.
There is a specific type of corrosion, known as rebar corrosion, which is generally found in concrete structures. In rebar corrosion, chloride ions slowly migrate into the concrete, leading to corrosion of the iron or steel beams. If you are wondering how do you prevent corrosion damage, the answer is by testing it regularly.
And if you want the best rebar corrosion testing services, choose only C3S. We have more than 25 years of experience in the field of concrete construction and testing.
Rebar Testing Services We Offer
The services we offer for rebar corrosion testing are:
- Carbonation Depth Measurement Test
This is a destructive test that tells us how deep the corrosive agents have reached inside the structure. This test is extremely important in preventing excessive damage to reinforced concrete structures due to rebar corrosion. The cement paste used in construction has a pH level of 13, and acts as a protective coating for the steel.
But over time, the CO2 present in the atmosphere leads to carbonation in the concrete. This carbonation reduces the pH level. Once the pH level falls below 11, the protective layer starts to lose its abilities. The carbonation depth measurement test helps determine how far the carbonation has reached.
In the test, a Phenolphthalein indicator is used for detection. If the indicator comes in contact with concrete below a pH level of 9, it turns pink. The test is conducted by spraying the indicator on a freshly split core of the structure. It can also be done by spraying the indicator on powder taken by drilling in the structure. The test is great for identifying how close the iron is to getting corroded.
- Soluble Chloride Content Test
Water soluble chloride ions can also lead to corrosion of reinforced steel. Chlorides are generally present in all types of concrete. But if the chloride content gets too high, it can cause corrosion. Generally, the threshold is 0.3% of the chloride content by weight of concrete. This test is especially important during rehabilitation and repair, when a portion of the structure is exposed to a water body. It is also useful for structures that constantly face salt application for the removal of ice.
For the test, samples are taken using a rotary drill at successive half inch depths, until the level of rebar is reached. Then the chloride content for each depth is measured through the Acid-Soluble Chloride in Mortar and Concrete test. A graph is then plotted for the different depths and respective chloride contents. This gives a detailed chloride ion profile of the structure.
If you want to protect your concrete structure with the help of rebar corrosion testing, contact us now. Our highly experienced team of engineers, technicians and inspectors will carefully inspect the property and help you build structures that stand the test of time.
At C3S, we offer concrete consultation services for all, whether you are a public agency, construction company, private homeowner, or an engineer.