Steel buildings are a perfect solution to an industrial building requiring any size of the crane, whether they are top running, underhung, monorails or jib cranes. Frames can easily be designed to suit top running cranes, utilizing either corbels (brackets on columns), stepped crane columns, or independent crane columns. Typically, cranes with a 20 ton or less capacity can be supported by brackets welded to the columns. Heavier cranes will likely require stepped or independent crane columns.
The following are things to consider when your steel building needs to support cranes:
Hook height: This measurement determines how high the runway beams are from the floor and the clear height needed inside your building.
Crane capacity: The maximum weight the crane needs to lift will determine how the building structure needs to be designed to accommodate these loads.
Crane span: The span (centerline of rail to centerline of rail) will determine how wide the building needs to be to provide proper interior horizontal clearance.
Runway beams (simple vs continuous span): Steel buildings are typically designed to support simple span runway beams which places a similar load at each column where the runway beams meet. Continuous span beams create a much greater center load on a column where the runway beam continues to the next frame.
Crane control systems (pendant, radio, and cab controlled): Radio-controlled cranes are becoming more commonplace – this type of control system increases lateral deflection and needs to be considered in building design. Cab controlled crane systems have significantly higher deflection criteria.
Column mounted jib cranes: Capacity, the elevation of jib crane boom/top brace and length of crane boom determine the thrust/pull forces and load onto the column.
Crane Service Class: There are tighter restrictions on Service Class E and F cranes that will be accounted for in the design of the building and the crane.
Crane bracing: Cranes require bracing that may consist of rods, tube struts, tiebacks/lattice bracing, or portal frames. Rod bracing may extend to the floor – if rods interfere with exterior wall openings or if access is required between interior modules, partial height portal frames can be utilized.
Multiple cranes: If there are two or more cranes operating on the same runway, will they be able to pick up full loads together in any single-bay?
Crane maintenance platforms: Fixed permanent maintenance platforms on the bridge will add significantly to the crane bridge weight and increases the reactions and the wheel loads.
Work with your crane supplier to determine the best solution to meeting your lifting requirements and your metal building supplier to efficiently accommodate the required crane loads.