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March 25, 2019

Factors That Cause Cracks In The Concrete Floor

Many people wonder just why something as strong as a concrete floor can crack. Cracks can appear even soon after a foundation has been poured. There are a few reasons why concrete floor crack, Concrete Polishing Companies in Brisbane will ensure that your floor is poured correctly and crack free

When a concrete floor is installed properly, it’s a long lasting and durable product, but it is very important that contractors follow well-established guidelines when mixing and pouring concrete.

It’s actually rare to find a concrete floor that doesn’t have settlement cracks and most standard concrete floors have at least one crack in them.

So why does concrete crack?

  • Excess water in the mix

Concrete for residential floors tend to have excess water because this makes the concrete easier to install. The problem is that it greatly reduces the concrete’s strength, making it prone to cracking

With a very wet mix, the concrete will shrink as the excess water evaporates the wetter or soupier the mix the greater the shrinkage will be causing cracking.

A concrete slab can shrink by as much as 1/2 inch per every 100 feet. This shrinkage effect causes forces in the concrete that will literally pull the slab apart. Cracks are just the end result of these forces.

So what you can do about it

Make sure the ready mix company is making the cement to the required specifications. If the floor is going to be polished ask the polisher to check on the quality of the pour. Usually, they will want to be in full control of the pour as this will have a huge impact on the quality and ease of their work.

  • Concrete drying out too fast

When concrete dries rather than cures it significantly increases the likelihood of it cracking. The chemical reaction that happens to allow concrete to cure or go from being liquid to being solid takes only a few hours, but the chemical reaction, or hydration, will continue for up to 30 days. If the concrete floor is allowed to dry out, then this reaction may stop and the floor will not gain its full potential strength to occur for days and weeks after you pour the concrete.

It is often necessary to add extra water by lightly hosing down the floor or covering it with a cloth that is wet, so the water in the slab will not evaporate

  • Using the wrong strength concrete for the job

Cement powdered or concrete is available in many different strengths and it depends on the specifications of the job which strength or particular mix of cement you need. So it’s important to verify with the engineer or architect which mixture needs to be used for your job. Then talk to the ready mix supplier

  • Control Joints

Control joints are there so that the concrete will crack where specified and often large floors have expansion joints because of the effect of temperature changes on the floor.

Concrete floors crack for several reasons, it could be because there’s too much water in the mix, because the surface below the concrete is not properly prepared or the wrong mixture of cement powder is used to make the concrete.