Debates in Grain Silo Restoration: Cost, Intended Use, Resistance to Coatings

When it comes to the maintenance and restoration of concrete storage units such as grain silos, the most common problem that we see every day is cost. Most facilities, over the last decade, have invested whatever funds are available into equipment, and the restoration budget usually takes the hit. The problem is that the deterioration process is a pyramid in nature. The observed small problem or failure not corrected immediately deteriorates exponentially as time passes. The repair costs increase exponentially as well. Now that so much time has passed since companies have invested in their storage facility, the cost of restoration is usually a shock.

Two items usually create debate. The first is that storage facilities, especially the ones built prior to the 1970’s, were not always designed or constructed to be used in the fashion that they are today. With the advancements in grain handling equipment, these storage units are loaded and unloaded more often, which overstresses them. If left unchecked, the result is structural fracturing and concrete failures. Improper lapping of rebar and insufficient or corroded reinforcing are both contributors to potential failures especially when subjected to increased stresses that are placed on them today vs. 40 or 50 years ago.

The second debate is the use of protective coatings or treatments to extend the service life of the storage unit by protecting it from deterioration due to moisture intrusion or carbonation. For years there have been various types of coatings that have been applied to the sidewalls or tops of storage units. Some of these coatings actually turned out to be the wrong thing to do and actually have intensified deterioration by trapping moisture. So a number of our clients have a “no coating” philosophy based on prior bad experiences. The challenge is trying to change this mindset.

We feel that the new technologies of coatings and membranes, if used correctly and in proper applications, can protect the storage unit thus adding service life.