Outdoor lifting systems
These constitute a specific variant of gantry cranes and are characterized by having one or two ground support legs, so they are lifting systems that no longer slide completely overhead. This solution is adopted when there is no possibility of taking advantage of an appropriate support structure for the cranes, which are often installed in an open area (yards, etc.).
In addition to the traditional, single-beam or double-beam versions, there are lame gantry cranes, in which only one wheel-bearing header slides overhead, while the other slides on the ground.
Torsional gantry cranes, on the other hand, are appropriately configured for handling large structures (e.g., very long concrete beams).