Concrete is pretty much everywhere; in bridges, buildings, roads, even in our homes. We often take it for granted because it’s concrete and it’ll last forever, right? But even though concrete is tough and lasts long, nothing is indestructible, and the clock is always ticking.
What happens if that bridge you cross every day isn’t as solid as it seems? That would be a good intro to a horror movie. But the fact is, concrete won’t last forever, and we need to know how to assess its lifespan and, if possible, prolong it.
Evaluating the Lifespan
Sometimes, you can easily see what state the concrete is in, and other times, you need technology to do it for you.
Here’s how you can evaluate the lifespan of concrete structures.
Visual Inspection
Basically, you come up to the structure and see if there’s any damage (in a nutshell). But even though it’s simplistic on paper, it requires expertise to actually identify damage.
A proper visual inspection involves looking for signs of cracks, spalling, discoloration, or exposed reinforcements. Cracks can be tiny, but even if they are, it’s still a sign of damage and it can be (and likely is) an indicator of a bigger underlying structural issue. Spalling suggests that there are whole chunks of concrete that have separated, and that’s usually because of water or freeze-thaw cycles.
Discoloration usually points to problems caused by water, and exposed reinforcements could be a sign of corrosion.
Non-Destructive Testing
This is a way to evaluate the structure without causing damage to it, and you may have heard it being referred to as NDT.
Ultrasound testing is one great example of NDT; it uses ultrasound rays to detect internal cracks and holes that you can’t see by just looking at the structure.
The rebound hammer test is another very common method that measures how hard the concrete is to see how strong it is overall. This is an indirect, but still quick and effective way to find weak areas.
Infrared thermography is especially useful in checking moisture intrusion or hidden voids. This method detects changes in temperature within concrete and it can pinpoint areas that are risky because of damage caused by either water or thermal stress.
Core Sampling
Core sampling is used for a more detailed evaluation. The way it works is by extracting small cylindrical samples of concrete and then the samples are tested in a lab. This method accurately measures compressive strength and it shows the chemical composition.
Sometimes, the testing can reveal harmful changes, like carbonation or chloride penetration, both of which can deteriorate the concrete faster.
Load Testing
This method of testing simulates the real-world stress the structure is expected to go through during its lifespan, so the engineers can see how it’s going to perform.
They apply loads to the structure and then look at how it responds to it. They’ll check to see if there are any signs of deflection, cracking, or other weaknesses.
Load testing is very useful when you need to see whether an older structure can still handle the intended load or if it needs to be reinforced.
Monitoring with Embedded Sensors
Modern technology has introduced embedded sensors to monitor concrete structures on a continuous basis. For example, sensors in bridge columns can provide real-time data to predict potential failures, which can avoid potential catastrophes and minimize risk, damage, and costs. The sensors are installed during construction, but they can also be retrofitted into existing structures.
They track factors like stress, temperature, and moisture levels. Over time, the data the sensors collect can help identify trends and predict issues before they become big problems.
How to Prolong the Lifespan
Concrete can last for a very long time, but it won’t if it’s not maintained. If you own a property, maintenance isn’t something you should skip on.
Repairing Cracks
Cracks seem like tiny, insignificant issues, but they can quickly become expensive problems. Fix the cracks as soon as you notice them. You can use epoxy injections or cement to patch the cracks.
Fixing Unevenness
An uneven concrete surface is an eyesore, but it’s also dangerous.
You’ll need a professional to fix this, so google “concrete lifting near me” and look for someone (a contractor) to help you out. Concrete lifting is very effective; you inject specialized material under the slab and raise it back to its original position.
Applying Sealant
Sealants create a barrier between concrete and moisture or chemicals.
The freeze-thaw cycle can be very damaging, and sealants can prevent this because they stop the water from getting to the surface.
Cleaning
Of course, cleaning is a must because it prevents dirt, debris, and salt buildup. Pressure washing and scrubbing are very effective at removing the contaminants.
Conclusion
Concrete isn’t indestructible, so don’t treat it like it is. Damage doesn’t happen overnight, but the good news is, there are ways to check whether the structure needs to be repaired or not.
Keep in mind that a tiny crack can indicate a serious problem underneath the surface, but even if it doesn’t, it still needs to be patched up immediately.
Don’t neglect maintenance and concrete should last you for a very, very long time.