DAMPING PADS FOR STACKS

FAQ'S

How do Damping Pads Work?

It has been well documented that elastic foundations provide more structural damping than rigid foundations.  The damping pads introduce elasticity into the foundation which increases the inherent structural damping.  This results in reduced vibration amplitudes.  In fact, damping pads are listed in ASME-STS-1 as an acceptable means to dampen a stack.

How Much Damping Can Be Achieved?

Field tests have been performed which indicate that critical damping values of up to 0.03 have been achieved.  To be conservative, we recommend designs assume a critical damping of 0.015.

Will This Cause the Stack to See Larger Lateral Deflections Due to Along Wind Loads?

The damping pads do introduce some elasticity into the base, but they are also very stiff.  There will be minimal impact on the lateral deflection due to along wind loads.

Do the Pads Hold up Over Time?

These pads have been in service for up to 30 years, with no reported problems.

Can Pads be Used on Existing Stacks?