The concrete foundation supports the steel building and resists the loads imposed by the building and site specific climatic load imposed on the building. In order to design a steel building foundation, the building engineers provide reactionary loading and anchor bolt requirements. This information, along with site specific geotechnical reports, will allow the foundation engineers to design the required supporting foundation. A typical pre-engineered steel building is built on one of two standard foundation designs.
The first design type is a spread footing design, or T shaped footing. Under each steel building column are spread footings installed below the frost line with pilasters that extended to the underside of the steel column. A grade beam or continuous wall joins the pilasters and footing and is continuous around the building perimeter. Lastly, the slab is poured between the grade beam.
The second is a thickened edge or slab on grade foundation. This style of design is generally used for small pre-engineered steel buildings. This foundation is simply a slab on grade with thickening of the slab as required for steel building columns, interior walls, or any other extra loads. This design style is economical for areas with a shallow frost level