Spalling repair the causes, identification and how it is repaired. Dafco, Spalling Repair Experts
Identification of Spalling.
Spalling (Concrete Cancer) is most often identified by signs such as flaking (concrete spalling), rust stains that leach from the concrete, bulging of the concrete or in some cases even fall off the building.The real problem lies within the concrete itself and is not a result of weathering.
Cause of Spalling.
As a general rule, Spalling is caused by the steel reinforcing within a concrete slab rusting. As steel rusts, it can expand more than 7 times its original size causing the surrounding concrete to be discoloured, displaced and flakey.
The process can start in many ways, but generally, it is due to one of the following:
- Poorly treated reinforcing steel being used in the original pour of the slab.
- The reinforcing steel being too close to the surface allowing water to seep through concrete and react with the steel.
- Incompatible metals being used in close proximity to each other, thus causing a reaction.
- Fractures in the concrete allowing water to penetrate the concrete and react with the steel.
Spalled concrete is an eyesore and a hazard. Over time, with increased exposure to the elements, falling concrete debris causing likely injury and damage to property. Spalling concrete should be repaired immediately, as deferring the treatment will inevitably lead to increased problems into the future.
Furthermore, any attempts to fix the problem for the short-term (such as parging over the problem) will only exacerbate the issue. Despite, potentially looking better, the rusting process will continue below the surface causing the steel to again displace the concrete and in some cases rust so badly the steel eventually needs replacement. Treatment and repair of the concrete is the best solution.
Spalling repair and how it’s done by the professionals.
Firstly identifying the spalling problems in the building mainly found in the slabs and support beams making sure not to miss any as it would lead the surface having to be repaired and repainted sooner than is necessary.
Once affected the areas have been identified and marked the spalling repairs can begin in earnest. Starting with the removal of the surrounding concrete and plaster exposing the offending steel supports making sure to expose all of the rusted steel to ensure an effective repair.
Once exposed we are able to determine whether or not the steel support needs replacing or if we can repair. If the steel is repairable we grind back the rust to expose the unaffected steel and proceed to repair the process.
A.B.E Spalling Repair Kit.
After years in the industry we have found that the ABE spalling repair kit to provide the most reliable results and the best long term permanent repair. The exposed steel is coated with a chemical treatment that retards rust and acts as a barrier to an further moisture. Then a concrete mix treated and applied to the surface that will then be professionally finished and you would never even know that we had worked on the area.
We know spalling repair.
Our professional teams in KZN, Port Elizabeth and George have extensive experience and training in spalling repair, having successfully completed many linear kilometers of of spalling repair and building rehabilitation.
We are standing by to chat to you about any questions you may have regarding spalling repair or to quote on your next project.
You can also visit A.B.E website for more technical information on spalling repair.