When grain bins break
August 16, 2017
A common concern with grain storage is how to avoid contamination from mycotoxins and other issues. Another danger that some may overlook: grain bin collapses.
They don’t happen often, but when they do, consequences can be expensive and at times, deadly. Equipment can be destroyed by the rush of flooding grain, hundreds of thousands of bushels can be wasted and humans in the way have lost their lives.
Fortunately, loss of life was not a concern earlier this month when a grain bin in the U.S. state of Nebraska suffered a breach one Sunday evening. Over a million bushels poured out, leaving a mountain of grain noticeable from the highway a half-mile away. An employee checked the bin less than a half-hour before the collapse and noted no issues, and the damage was later noticed by a passerby. Officials estimate the corn on the ground was worth $4 to $5 million. Because it was a Sunday evening, few were around the grain elevator, so no one was hurt.
Major spills are usually the main problem with bin breakage, but in some cases, the cloud of grain dust that comes furling out after a collapse can ignite, leading to dangerous explosions.
What causes the bins to break? Grain Journal published an article citing that of commercial collapses handled by an insurance company they reached out to, both newer and older bins were often the culprits. Records show that 37% were 1–15 years old, 23% were 16–25 years old and 40% were 26 or more years old. Most contained between 10,001 and 100,000 bushels.
The pressure that grain places on the ground and the bin around it is immense, and only grows stronger as the bin gets taller. Testing for soil-bearing capabilities and adequate foundations are key. The Grain Journal article states that the default conservative value used by small farm bins is a 1,500 point spread function, but the number changes after 30 feet.
In its guide to avoiding bin failures, Feed and Grain draws on the Leaning Tower of Pisa to illustrate the value of testing soil. The ground around the famous Italian tower can’t support its weight, hence the lean. This is not a situation we want for grain bins. Even a slight lean leads to more pressure on one side, increasing the likelihood of a break in the bin wall. As such, trusted contractors should be used during construction, and grain needs to be properly unloaded every time. Weather conditions should also be monitored for events that might infringe on the bin’s integrity.
Perhaps most importantly, Feed and Grain recommends that inspections for rust, cracks and other signs of damage be conducted on a frequent, regular basis.
Category: Agriculture, Milling & Grain