When it comes to grain bulk storage there is one major consideration: moisture. Grain is meant to be stored dry and if moisture is in the storage facility, it can ruin the commodity. Professionals in the dry storage field have grappled with this issue. One solution to the problem is the Monolithic Dome, an effective storage facility for all bulk storage, especially grain.
A Monolithic Dome is a concrete structure constructed by inflating a membrane known as an Airform. While that membrane is inflated, polyurethane foam is sprayed to the interior surface. Steel reinforcing rebar is attached to the foam using a specifically engineered layout of horizontal and vertical rebar. Finally shotcrete, a spray mix of concrete, is applied to the interior surface of the dome. The structure is one solid piece, giving it several advantages over traditional square structures.
The foam inside the structure creates great insulation and allows the dome to be energy efficient. “Inside a dome we can control the moisture content more easily than any other building,” stated Gary Clark, vice president of sales for Monolithic Constructors, Inc. With the humidity so easily controlled, Clark stated the grain stores and moves better than in regular structures. This is advantageous because, according to Clark, “the dryer you can store grain the longer it will store.”
Another advantage provided by Monolithic Domes is the versatility of the structure. Clark stated the dome is more versatile than the traditional silo. “We can cover more ground than a silo could. We can build in different sizes to accommodate the size of the load,” he said. For example, a dome can be built wide with a low profile or narrow and high with a dome on top, depending on the storage needs.
These structures are also impervious to weather and natural disasters, keeping the commodity safe inside. If a fire were approaching the dome, the concrete structure would keep the fire out and leave the grain inside safe. If a fire were started inside, the dome would safely contain it. These domes have also been known to survive hurricanes, tornadoes, earthquakes, and other natural disasters. They are often built in tornado-prone areas to protect communities from those storms.
In addition to these major benefits, Monolithic Domes provide small benefits as well. These structures can be easily outfitted with any type of conveyor and reclaim system. It is mounted in the structure right off the dome, because “the dome itself can support the weight of the conveyor,” Clark stated. In addition to this, animals are easily kept out of the structure. “Because it is constructed in one solid piece, protection form vermin can more done easier,” Clark said.
John LeGrand was the owner of one of these structures and used it store grain. He owned Wheeler Grain Company near Rogersville, Alabama, USA. He oversaw the company until he sold it in 1994. Located at this company was a Monolithic Dome and it was used for commercial grain storage. Before he sold the company, he had been using this dome for 10 years. He stated that the dome “had been very satisfactory” to his company’s operations.
Further attesting to the advantages of the dome, LeGrand recounted how a fire broke out inside the structure at his company. The fire started not due to the structure, but rather the failure of the lessee to maintain the temperature sensing system. However, he recounted that the structure “survived an internal explosion with moderate damage.” When asked if he would recommend these structures to other professionals in the industry, he replied, “Yes, I liked it very much. It did a fine job of storing grain.”
Monolithic Domes began with David B. South and his interest in dome building. By 1976, he and his brothers Randy and Barry built their first dome. That project resulted in a patent for the process and launched an innovative construction system for Monolithic Domes. Several domes have been built around the world, and the uses include homes, schools, churches, and sports facilities.
The Monolithic Dome Institute was founded to promote the dome building industry as a whole. Its purpose is to educate and promote Monolithic Domes around the world. Headquartered in Italy, Texas, USA, it also holds special events such as workshops on how to build domes. Information about Monolithic Domes and the industry are updated on its website. The organization offers concept evaluations and feasibility studies for those interested in building a Monolithic Dome.
Note: This article appeared in the March 2017 issue of Dry Cargo International magazine.