The Mobile Launcher Platform (MLP) is a two-story structure used by NASA to support the Space Shuttle stack during its transportation from the Vehicle Assembly Building (VAB) to Launch Pad 39A at the Kennedy Space Center. It also serves as the vehicle’s launch platform.
A number of electronic cabinets are mounted inside the MLP. These cabinets must withstand the sound and vibration generated during the vehicle liftoff.
The following video link shows the earthquake-like vibration inside the MLP. The file has two segments. Note the ceiling-mounted pipe in the upper right corner in the second segment.
– Tom Irvine