Concrete is a durable material that can last for decades, but how long does it take for concrete to deteriorate? In reality, its lifespan is usually between 50 to 100 years, and sometimes less. Building codes and policies often require buildings to survive several decades, but deterioration can begin in as little as 10 years. There are several causes of concrete degradation, such as fire, aggregate expansion, seawater effects, bacterial corrosion, calcium leaching, physical damage and chemical damage (from carbonation, chlorides, sulphates and non-distilled water).To determine the life of the concrete, it is important to consider the environment, the installation process, the concrete used and the climate of the area. If installed correctly and taking all factors into account, concrete will last for many years.
If cracks or breaks in the concrete are observed over time, concrete experts can repair the material and restore it to last longer than ever. Concrete deterioration can cause major headaches for building owners. It is important to correctly identify these defects early and plan appropriate repair strategies. Concrete degradation can occur through scaling, disintegration, erosion, reinforcement corrosion, delamination, spalling, alkali-aggregate reactions and concrete cracking. When the concrete temperature exceeds 65 °C for too long at an early age, the crystallisation of ettringite (AFt) does not occur due to its higher solubility at elevated temperature and the less soluble monosulphate (AFm) is formed. When using concrete in a domestic project, it is important to consider certain factors to determine its durability and service life.
Researchers found that when one area of the concrete was stressed (crushed, stretched or bent), the C-S-H compounds dissolved into the concrete and were deposited in a nearby non-stressed area. The researchers used a combination of experimental and theoretical techniques to determine this mechanism: they used microindentation (which involves pressing a tiny, hard tip into concrete samples and observing their response) and vertical scanning interferometry (which involves imaging the C-S-H stains in 3D and measuring them as they shrink or grow). When the sections of the reinforcing bars are too small or the bars break locally, the reinforcement is lost and the concrete is no longer reinforced concrete. Carbonisation of concrete is a slow and continuous process that progresses from the outer surface inwards but slows down as the depth of diffusion increases. Exposure of concrete structures to neutrons and gamma radiation in nuclear power plants and high flux material test reactors can induce radiation damage to their concrete structural components.
The most common are those containing reactive silica which can react (in the presence of water) with the alkalis in concrete (K2O and Na2O mainly from cement). It is the water that converts the calcium silicate in the cement into very sticky compounds that can adhere to the aggregate forming the concrete. Often when other materials such as wood begin to deteriorate, the concrete frame of a building or house can be reused. Whenever you are planning a concrete project it is important to work with experts to use the best materials and ensure proper installation so that your project will last for decades. Carbon dioxide (CO2) from the atmosphere diffuses easily into leachate causing a chemical reaction that precipitates (deposits) calcium carbonate (CaCO3) on the exterior of the structure.
The corrosion that often occurs in the crown (top) of concrete culverts is directly attributable to this process known as crown corrosion. Concrete is capable of resisting weathering chemicals and abrasion if properly installed and maintained.
