Extend the Life of Steel Sheet Pile: Corrosion and Damage Protection
As previously discussed here on the Eiffel Trading blog, steel sheet pile comes in several shapes and styles, and with several types of interlock systems. This, along with sheet pile’s reputation for high durability and its ability to be used over and over again, make it one of the most sought-after items in our online marketplace.
Sheet pile has an exceptional service life. Certain environments are going to be harsher on your sheet pile installations than others, though. Luckily, we’ve compiled a list of some of the most common corrosion factors and tips to help extend the life of your steel sheet pile.
Corrosion
The most common factor of corrosion in steel is exposure to moisture and air over time. When steel is exposed to moisture, the environment in contact with the steel gains electrical conductivity, which weakens the surface of the steel. Common factors of corrosion include water and soil conditions, pollution, and weather.
Chlorides, pH Balance, and Salinity
Waters closer to the sea are more corrosive than freshwater due to higher salinities, but it’s also important to note that steel sheet pile in areas with a lot of water movement is going to be more affected than piles in areas with stationary bodies of water. Steel sheet piles used in marine construction or near saltwater are also susceptible to corrosion due to higher concentrations of salt in the air. Water with a pH of 7.2-8.2 are more likely to expedite corrosion.
Soil with larger grains offer greater exposure to air on the surface of the sheet pile, and disturbed or backfill soil tends to hold more oxygen. Soil with a pH of 7 or greater are more acidic and will therefore be more corrosive to steel. Sheet piles driven into undisturbed soil are less likely to experience corrosion.
Pollution
Both saltwater and freshwater are prone to pollution. Water can be polluted with industrial water, sewage, spilled oil, and more. Some pollutants increase the oxygen level in the water by killing organisms that depend on it, others alter the pH balance of the water.
Part of the reason soil may have a higher pH balance is contamination. Pollution, vegetation, and various chemicals can affect soil in different ways, which can have an effect on its interaction with steel (or other things, like water).
Weather
Wind and rain can have an effect on the surface of steel sheet piles, especially in marine construction situations or areas near saltwater. Wind can carry saltwater mist, and rain trapped in crevices can trigger corrosion as it creates damp conditions.
Protection
Steel will inevitably corrode during its lifetime, but by taking proper preventative measures, you can greatly extend the service life of your steel sheet pile. The most common preventative measures for protecting steel sheet pile include coating and using thicker or corrosion-resistant steel.
Corrosion-Resistant Coating
There are several options for sheet pile coating, which engineers should be aware of and take advantage of, especially in marine construction situations. Zinc coating is one of the most common types of corrosion-resistant coating; it can be applied by plating or hot-dipped galvanizing. Zinc coating will usually corrode before the steel is even attacked by the electrical conductivity.
Another popular type of coating is epoxy or paint. These coatings are primarily used to prevent soil and atmospheric corrosion. The cost and durability of coating depends on the type used (paint is cheaper and effective, but coal tar is extremely durable and much more costly).
Some coatings can also be applied after corrosion has begun, to prevent its spread. Steel sheet pile may be re-coated many times over its lifetime.
Corrosion-Resistant Steel
There is a marine-grade steel option. The ATSM has designated ‘ATSM A690’, Grade 50, as “mariner-grade” steel. Steel sheet piles made with ATSM A690 have a greater resistance to splash zones corrosion, thanks to added nickel and copper in the steel’s manufacturing process. Mariners’ steel has some of the longest service life of any treated steel sheet pile.
Be Prepared to Experience Some Corrosion Over Time
Always rely on the project engineer to help determine the chances and rate of corrosion, and to recommend ways to prevent or decelerate the process. This will enable you to use your sheet pile over and over again – or to sell it used and improve the ROI of your project!
Buy and Sell Used Sheet Pile with Eiffel Trading
Eiffel Trading currently has several options for used sheet pile for sale (including PZ/PZC sheet pile, PS sheet pile, AZ/NZ/ZZ/Hoesch sheet pile, and cold-rolled sheet pile) as well as used combined wall systems available on our marketplace. Don’t see the type of sheet pile you need? Create a wanted listing for free today.
Learn more about selling with Eiffel Trading to get started selling your used sheet pile and other materials today.
If you would like more information or further assistance, call us at 1-800-541-7998 or email sales@eiffeltrading.com.