Dealing with contaminated concrete floors can be a challenge for any contractor, and recently we heard of another success story involving colloidal silica and a workshop floor that was in dire need of some help.

The floor in question

The worksite was a 30-year old engineering workshop floor that had oil and various other contaminates dropped on the concrete over the years.

Oil is a weak acid, and this constant exposure resulted in it corroding the concrete’s capillaries, weakening its structure and making it more susceptible to further contamination, which would continue to penetrate deeper into the concrete.

This meant that the problem had become pervasive, and that a colloidal silica was the best solution.

Why use a colloidal silica?

Densi Crete is a 100% colloidal silica that not only is able to improve concrete of any age, but it is also capable of decontaminating old concrete slabs.

This is because Densi Crete forms a permanent gel deep inside the concrete that forces or purges substances out of the concrete, which include harmful chlorides, oils, acids, animal fluids, chemicals, microbes, mould, and gases.

After the Densi Crete is successfully applied, the contaminants will either be purged, or contained passively in the permanent gel, which allows for any coating or covering to be applied to the concrete without having to worry about the substrate being compromised.

In fact, Densi Crete is the only system that will permanently eliminate deep-seated contamination and halt the effects of moisture, thereby ensuring that floor coverings or coatings won’t delaminate from the concrete substrate.

Treating Contamination

Firstly, diamond grinding is required to remove the layers of grease and oil and then Densi Crete can be applied, purging the contaminants. The concrete will actually give off a foul smell as the Densi Crete purges the floor of deep seated gases and oil. Further diamond grinding maybe required, and more Densi Crete applied until all the materials are purged or encapsulated in its gel.

Afterwards, the concrete is cleaned, and the substrate is ready to receive subsequent coatings to protect it from future moisture and other contamination ingress.

The benefits of using Densi Crete:

• Densi Crete can be applied to almost any concrete product containing 10% Portland cement.
• It is easy to apply and can be sprayed on to existing concrete or concrete at time of pour.
• After applying Densi Crete the surface is foot traffic-able after just 1 hour.
• Install floor coverings within 24 hours of application to existing concrete or within 14 days of application if used at time of pour.
• Densi Crete is more than 21% cheaper than other waterproofing membrane methods.

For more information about DuraCore’s range of products, please feel free to contact us or visit www.duracore.com.au. Alternatively, to find your nearest distributor please click here.