Above-grade fitness centers can be an annoying source of vibration disturbance in buildings. Their potential impact is best evaluated at the design stage before people begin to use its treadmills, free weights, and exercise classes. Often the building does not yet exist and structural models provide the best way to evaluate potential impacts. The authors recently had the opportunity to compare finite element frequency response function (FRF) predictions to test data obtained in the field. The driving point accelerance predictions showed very good agreement with the test data up to 100 Hz. Cross-accelerance predictions from one point to another similarly showed good agreement with the test data. The test data also confirmed reciprocity when the drive and response points were interchanged. Test data in the field were obtained using both an instrumented force hammer and a drop weight with an accelerometer. Both methods produced consistent experimental FRFs. This study shows that a well-conceived finite element model can produce reasonable predictions of low-frequencystructural response.
Zapfe et al. (Tue,) studied this question.