In a report published by the Brisbane Times, last year, it described that many Brisbane and Gold Coast buildings in the City and on the Glitter Strip are coming under fire for looming concrete cancer concerns.
In a widespread awareness campaign, the Gold Coast City Council along with Queensland’s strata title authorities including Strata Community Australia, have suggested that over the next few years issues with the structural integrity of many buildings built 40 years ago will need immediate repair, to stay structurally sound for commercial and private use.
Concrete cancer or spalling concrete as it’s sometimes referred to as caused by the corrosion of steel in concrete.
So how does this occur?
Three key ingredients cause concrete cancer – Iron, Water and Oxygen, and the process starts when:
– Moisture hits the internal steel iron, and combines with the carbon dioxide in the air, forming weak carbonic acid.
– As this acid forms, it causes the iron to dissolve, allowing water to start breaking down its components – hydrogen and oxygen.
– This then forms an oxygen and iron bond freeing electrons, creating what is commonly known as rust.
Hi-rise apartment buildings built back in the 1970s have been the hot topic of discussion, as the effects of concrete cancer are starting to show, some with disastrous outcomes.
We all remember the iconic Iluka building in Surfers Paradise. Back when Meter Maids were the hot topic on the tourist strip. The Iluka building was the first multi-storey apartment block to cast shadows along Surfers Paradise beach. After more than 40 years of standing proud, it was demolished in 2013 because of concrete cancer destroying the structural integrity of the building.
It’s not always obvious what underlying problems are in a concrete structure, however cracking, honeycombing and spalling are relatively easy to locate. The real concern is the root of the problem and without proper technical support can be easily overlooked.
Things to look for are:
-Reddish/brown stains that are adjacent to cracked concrete or running down any part of a building.
-Concrete lifting/exploding out.
-Other cracks with signs of moisture coming through, they can sometimes look like white crystals or fluorescence.
The process to fix Concrete Cancer can be long and most times if left unattended quite expensive. Things BRS consider are:
-Determine what is causing the problem
-Evaluate the severity of the damage i.e. classification, major/minor
–Determine the repair or rebuilding method
-Preparation of existing concrete and steel. Sometimes inclusive of additional reinforcing steel anodes
-Formwork and repair products
-Allow for proper curing of the repairs. Often includes specialist coatings
-Finishing and making good to original, profiles, textures, paints and protective coatings
–Establish a site-specific manual, recording the details of repaired areas
-Protection of the concrete is essential in reducing further external influences
For more information on how BRS Building Rectification Services can help you with Concrete Repair or any other services, please call BRS Building Rectification Services (07) 5539 3588 or email email@example.com