CONCRETE CANCER - A SERIOUS EPIDEMIC
Reinforced concrete (RC) is arguably the major construction material of our time. Concrete structures are strengthened by layers of steel bars placed close to the surfaces. Whilst concrete has a history of durability, in the modern environment it is under increasing attack.
Aging concrete often becomes contaminated, leading to the deterioration in the form of corrosion of the steel reinforcing bars known as concrete cancer.
Concrete Cancer is currently one of the most prevalent problems for the owners of steel reinforced concrete structures. It's an issue which is costing millions in repairs and rebuilds across the globe..
WHAT IS CONCRETE CANCER? It is a serious problem that occurs within concrete, caused by water and contaminates entering the capillaries and cracks in concrete, causing the steel reinforcing inside to rust (there is also carbonation attack). As the steel rusts, it expands, causing the concrete around the steel to be displaced. As the concrete becomes more displaced, more water and contaminants gets into the steel, causing further rusting and the problem gets worse. The expansion of the steel causes the concrete to delaminate, and results in spalling and compromises structural integrity. Spalling is where the concrete initially cracks, and then starts to break away. While spalled concrete is asthetically unappealing, it can also be dangerous as concrete pieces may fall off and in most cases cause damage and/or injury to people.