Corrosion is not always easily detected or visible to the naked eye. Once this corrosion begins, decay rapidly accelerates, leading to structural failure, loss of capital investment and potential loss of life.
Corrosion causes infrastructures to slowly deteriorate and crumble. Bridges, steel-reinforced concrete and pipelines are widely affected. Unfortunately in such structures, corrosion is not always easily detected or visible to the naked eye. This makes it especially dangerous because the corrosion will ultimately lead to structural failure, loss of capital investment, environmental damage, and perhaps even loss of life.
The Montana State University states that the United State's economy is faced with an estimated yearly cost of $276 billion dollars from metallic corrosion. In 2013, a report card on infrastructure in the United States was issued by the American Society of Civil Engineers. On the report, the nation's infrastructure received an overall D+ rating. The report went on to state that approximately $3.6 trillion would be needed by 2020 to repair and stop the corrosive process in the nation's bridges, tunnels, roadways and pipelines. The American Society of Civil Engineers (ASCE) cited that the leading cause of the nation's crumbling infrastructure is rampant corrosion.
Concrete remains the most widely used construction material in the United States and around the world. Unfortunately, to make concrete stable it has required steel to reinforce its strength. In recent years, environmentally friendly fibers to replace steel within concrete have been developed and are being tested with varying rates of success.
In the past, corrosion in concrete infrastructure and other structures has been considered inevitable. Metal material's properties naturally interact with the surrounding environment and a chemical reaction occurs. The most common metal corrosion is basic rust which happens from iron oxidation which is a reaction of iron to oxygen exposure. There are ten other types of corrosion that are commonly encountered in failing infrastructures:
- Localized Corrosion
- General Attack Corrosion
- Environmental Cracking
- Galvanic Corrosion
- Flow Assisted Corrosion
- Inter-granular Corrosion
- High Temperature Corrosion
- Fretting Corrosion
Once corrosion occurs, the decay rapidly accelerates. There are methods that can slow or control the corrosive process such as applying protective coatings and linings, cathodic protection, corrosion-resistant materials, and utilizing inhibitors.
Coatings and linings are generally applied with cathodic protection systems. Such a system is considered cost-effective compared to other methods.
The use of cathodic protection (CP) involves using direct electrical currents to counteract the natural process of external corrosion of a structure's metal components. Such steps are often taken on bridges that contain metal that is corroding. The CP process is also used on new structures to prevent corrosion from starting.
In recent years, prior to construction starting, many designers are considering and using corrosion-resistant materials such as steels, plastics, and special alloys. Prior to using corrosive resistant materials several factors must be taken into consideration such as the foreseeable life span of the structure and the climatic region where the materials will be used. In some situations, modifying the surrounding environment so it is not conducive to corrosion by reducing moisture and improving drainage is more cost-effective and simple than using corrosion-resistant materials.
Ultimately, corrosion prevention should be the goal of all engineers, designers and architects by paying attention to a structure's design and the materials used in construction. There is very little doubt that preventing corrosion saves big bucks in the long run compared to the exorbitant costs of repairing corroded structures. Billions of dollars worth of repair, maintenance and replacement costs can be saved by working to prevent corrosion. Without corrosion causing a structure's early demise and destabilization the service life of most infrastructure is significantly lengthened, public safety is secured and the environment is protected.
For over 25 years, APP has provided composite technology options that offer excellent protection against corrosion which prolongs the life of valuable piping systems. Please contact us to learn about our history and corrosion prevention technologies.