Sun. Dec 22nd, 2024

Common Myths About Concrete

Introduction

With concrete being one of the most widely used construction materials people have created a lot of misconceptions around it. That’s why it’s best to hire a professional for constructing your driveway or pathway. To do that you can search for “paving companies near me”. Let’s check out some common myths about concrete and bust them. 

The Myths

  1. Stronger concrete isn’t more durable – Strength and durability go hand in hand. That’s why people often think that stronger concrete is more durable and is going to last them for a longer time. While concrete has high comprehensive strength, it isn’t the only factor that determines its durability. Sometimes those factors can reduce the strength of concrete. For instance, increasing permeability can increase durability but decreases strength. 

Moreover, the environment has a great effect on concrete’s durability. For instance, if the concrete is constantly being exposed to an alkali-silica reaction it would deteriorate very quickly. That reaction would corrode reinforced steel inside the concrete. Moreover, if you live in a place with extremely harsh winters stick to stone or other materials for your driveway or pathway. The freeze and thaw cycles can easily bring down the life expectancy of concrete. 

  1. Concrete isn’t impermeable – If you’ve read the above-mentioned myth, you know that concrete isn’t impermeable. While concrete is solid, it does allow liquid to pass through. Even the densest concrete will have some level of porousness. That means everything from water to oil and chemicals can pass through the concrete at some level in both liquid and vapor form. 

For checking permeability, you need to get concrete mixes with high cement to water ratio. They also need to have a higher ratio of well-graded aggregate and plasticizers or other chemical admixtures. Moreover, you can also coat the concrete surface with sealers to reduce its permeability and liquid absorption. For instance, if you’re in the garage and you want the concrete floor to have minimum permeability, the concrete needs to be surface treated with sealants. 

  1. Adding water isn’t the only way to increase slump – Slump basically measures the workability of concrete. Adding water is just one of the ways to add slump. However, it has many drawbacks. Adding water increases slump by just one inch, it brings down the comprehensive strength by as much as 200psi and also increases shrinkage. This way of adding slump also wastes a lot of cement. 

Instead, superplasticizers or water reducers can be used to add slump without changing the water-to-cement ratio. The maximum size and grading of the aggregates affect the workability of the concrete. Throughout the day you can measure and correct for moisture content and variations of aggregates and adjust accordingly. Unloading time also needs to be measured so that slump isn’t decreased.  

  1. Water doesn’t damage concrete – There is a gross misconception about water damaging concrete. This couldn’t be further from the truth since water is essential for concrete finishing. Water is used for curing the concrete. During the curing process, water gets vaporized from the concrete and that’s why water needs to be added to hydrate and make the concrete stronger while it cures. 

Fresh concrete will continue to be hydrated as long as there’s enough moisture at the right temperature. The curing process stops when there is no moisture and relative humidity dips below 80 percent. Hydration also slows down drastically when the concrete reaches freezing temperatures below 5 degrees Celsius. 

On the other hand, if the temperature is too high there’s drastic moisture loss that can crack the concrete. That’s why concrete needs to be cured at the right temperature and should be hydrated as long as possible to make it strong and long-lasting. 

  1. Concrete is eco-friendly – Cement is required for making concrete and that’s why people often associate concrete with the bad environmental effects of the cement industry. While the cement industry releases a lot of carbon emissions into the atmosphere, concrete is actually good for the environment. Concrete is one of the strongest and most durable materials in the construction industry and offers high value for money. 

Since it can last for several decades and requires minimal repairs and maintenance, it’s great for the long term. In the long term, it uses less energy and fewer materials and has a small carbon footprint. Moreover, concrete has more value in being recycled instead of ending up at the landfill. That’s why the construction industry has seen rapid growth in concrete recycling. 

  1. Reinforced concrete can crack – People have many wrong assumptions about reinforced concrete. Contrary to popular belief reinforced concrete can crack. Even with steel reinforcement, concrete that doesn’t move with volume changes has weak tension areas and can easily get cracked. While structural reinforcement doesn’t prevent cracks, it holds them together.      

So even if you have your driveway built with reinforced concrete, extreme freeze, and thaw cycles during the winter can develop cracks. When concrete does crack the tensile stress of the concrete is transferred to the steel and this allows the concrete slab to hold its own against a heavier tensile load. 

  1. Concrete isn’t cold – Here’s another misconception that has had many positive effects on the concrete industry in warm regions. However, concrete isn’t cold. It can absorb and retain heat quite well and then slowly releases it throughout the day. That makes concrete even warmer than ceramic or stone tiles. If you want to install underfloor heating concrete is a superior option compared to most other options on the market. 

While underfloor heating with concrete floors requires extra care during the initial stages, it is necessary for maintaining the finish. The concrete needs a lot of time to cure properly before the heating system can be turned on. While you will feel cold at first, over the next few days the heat rises gradually to comfortable levels.  

Conclusion

By now you must be surprised to know that so much ‘common knowledge’ about concrete was simply myths. That’s why when you’re building a driveway or pathway, it’s best to hire professionals for the job by searching for “paving companies near me”.

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