Good Vibrations? Measuring, Feeling, and Fixing Building Motion

Building vibrations are often treated as an afterthought until occupants complain, equipment malfunctions, or adjacent construction raises concerns. For design engineers, however, vibration serviceability is a practical design consideration that spans multiple levels of performance: protection from damage, human comfort and annoyance, sensitive equipment performance, and construction-related risk.

This interactive presentation will provide a practical framework for understanding and evaluating vibration in buildings. We will discuss common vibration sources, including footfall, mechanical equipment, fitness uses, transit, and adjacent construction; how vibration levels are measured and interpreted using acceleration, velocity, frequency, damping, and duration; and how different criteria apply depending on whether the concern is structural damage, human perception, or sensitive equipment. Guidance documents and criteria such as AISC Design Guide 11, ISO-based human comfort criteria, construction vibration limits, and vibration criteria for sensitive equipment will be discussed from the perspective of what a building design engineer needs to know.

Using live demonstrations with seismographs, wired and wireless accelerometers, an active mass damper, and potentially a laser vibrometer, attendees will see how vibration is measured, processed, and interpreted in real time. Participants will also experience controlled vibration levels to connect design criteria with human perception. The session will close with a practical discussion of how vibration issues can be modeled and mitigated, including finite element model calibration, stiffening, added mass, damping, tuned mass dampers, active control, and retrofit decision-making.