- In a seismic application where vibration isolation of the mechanical equipment is required, this movement for proper isolation is still necessary. However, in these installations, the lateral & vertical movement of the equipment needs to be minimized so that equipment remains in place during a seismic event.
- Holding down the equipment can be achieved in two ways, a mechanical snubbing device can be placed in conjunction with “standard” spring isolators or spring isolators with “built in” snubbing devices can be used. These are what we refer to as seismic isolators.
Floor Mounted Seismic Vibration Isolators
- In this restraint method, the equipment rests on isolators that have built-in restraint.
Seismic Restraints & Bracing
- Seismic forces are exerted on a building and its contents during an earthquake. These forces act horizontally upon the structure itself, as well as the piping, cable trays, duct work, and other building systems within.
- Typical supports for piping, trays, and other equipment are designed for the gravity, or vertical, loads but do not take into account the horizontal loading caused by earthquakes.
- Seismic restraints (i.e. braces) resist the horizontal forces and keep the systems in place and secure.
- The main purpose of seismic bracing is safety- to minimize the loss of life due to an earthquake.
- Picture Credits: VMC USA