Reuben Hale, P.E.
Ph: (510) 507-1300
Floor Vibration Sensitivity Testing - Vertical slab-on-grade floor vibration sensitivity requires an understanding of the way vibration propagates in slab on grade floors and elevated floors. We have a number of methods for estimating this sensitivity where the floor is massive and stiff and vibration sources are assumed to be far from the tool. We have more involved tests and calcs for nearby sources that produce gradients. Estimates of horizontal floor vibration sensitivity and sensitivity to floor rotation are more challenging and we have methodologies that have proven to produce sound estimates of horizontal and rotational sensitivity to slab-on-grade floor vibration. In a nut shell, the floor vibration sensitivity is an estimate that involves the predicted (or measured) floor dynamics at the customer site.
The floor vibration sensitivity for upper floors often requires other methods of testing and present a different set of challenges. We have performed testing on many types of upper floor systems and understand the unique dynamics of these systems. An upper floor is both more flexible, and more resilient, and the coupling of the floor system is very important to consider.
Often customers will ask if they can just put their tool on a shake table. The answer depends on how well the shake table can control off axis response to the inertial forces of the payload, and how sensitive the system is to the other axes. Note that the floor often serves as a structural member, often unintended. The floor does not rotate as easily as a shake table and thus the response of the system under test to vertical vibration on a shake table will be very different than when it is supported by a slab-on-grade floor, and different again when mounted to an upper floor span where rotation and vertical displacement are coupled.
We enjoy this work and are happy to talk about specifics regarding isolations systems, various considerations involving various floor systems, and the inherent sensitivity of the product given its structure.
- Sensitivity Testing Topics Include:
Overview, Floor Vibration Sensitivity, Acoustic Noise Sensitivity, Magnetic Field Sensitivity