Understanding Aging Steel Structures

Once thought to be generally low-maintenance and reliable, steel structures have demonstrated that they do indeed degrade over time due to corrosion and mechanical damage. In order to stay on top of your structures’ condition, inspection at regular intervals is necessary to identify opportunities for restorations and life extension.

Original protection systems, including factory-applied coatings, attempt to mitigate corrosion by creating a barrier between the steel and the soil. As structures age, these initial protection systems deteriorate, allowing environmental influences to directly impact the steel itself. In many cases, deteriorating factory-applied coatings can cause more harm to structures because they allow moisture to make direct contact with the steel and hold the moisture against it, which accelerates the corrosion process.

Once the steel is exposed, the natural process of corrosion activity sets in and begins to thin and weaken the steel. This typically begins at the groundline and proceeds downward along the surface of the structure below grade.  Age alone is not an accurate predictor of which structures will experience corrosion. There is a wide range of factors that can contribute to corrosion and increase the rate at which a structure corrodes.

Structure Characteristics

  • Age
  • Structure type & design
  • Material type
  • Foundation construction
  • Existing coatings
  • Variations from construction standard

Environmental Conditions

  • Terrain & soil conditions
  • Moisture content
  • Stray current
  • Agricultural activity
  • Industrial emissions

Turnkey Solutions

As a turnkey solution provider, Osmose can assist utilities with every aspect of implementing a cyclical, steel infrastructure life-extension program. Osmose offers industry expertise to develop the most effective corrosion and concrete programs, engineering resources to design complex repairs, and field labor to thoroughly assess structures and install restoration solutions, cathodic protection, and protective coatings. 

To learn more, visit the Steel Inspection & Life Extension section of this website or contact your local Osmose professional.  Not sure who your local professional is?  Email steel@osmose.com to find out.