An operating platform sometimes referred to as a grade mounted platform or commonly as GMP, essentially consists of an elevated steel platform, usually around or close to an equipment or vessel. It has open bar gratings fitted over a grid of primary, secondary and tertiary beams. Though a staircase is usually used for access to the platform top, a caged ladder can replace it based on the frequency and type of access required as decided by the piping engineer.
The primary beams transfer all gravity loads onto their supporting columns. Column orientations are usually the same for all columns. Lateral force resisting system is by MR frames in one direction and braced frames in the other. All applicable load combinations are taken into consideration in design, for example, operating loads, blast loads, thermal loads, hydro-test loads & friction loads along with the critical nature of operational, engineering, and environmental conditions. For soils of moderate to high SBCs, the foundation system typically consists of pedestals over isolated footings.