Steel Floor Walking Vibration (AISC DG11)
AISC Design Guide 11 walking-vibration check.
Example
You enter
- Floor natural frequency fn (Hz) 5
- Effective panel weight W (lb) 30000
- Damping ratio beta 0.03
- Walker force P0 (lb) 65
- Occupancy limit ao/g 0.005
You get
- Peak acceleration ap/g 0.01255
Checked against published worked examples from: AISC Design Guide 11 (2nd ed.) walking-vibration check.
Details, formula, and sources
ScopePeak acceleration ap/g = P0 e^(-0.35 fn) / (beta W) against the occupancy limit (0.5% office/residence, 1.5% mall). Acceleration falls with frequency; the criterion is written for floors of about 3 to 9 Hz, the range walking harmonics excite, and flags a frequency outside it. The serviceability check strength alone misses.
Formula or tableap/g = P0 x e^(-0.35 x fn) / (beta x W); pass when ap/g <= ao/g.
Source and editionAISC Design Guide 11 (2nd ed.) walking-vibration serviceability check, by name.
Free accessAISC Design Guide 11 is available through AISC; the walking-vibration relation is a published serviceability check.
What governsEstimate. AHJ and licensed professional govern.
API field namesnatural_freq_hz, effective_wt_lb, damping_ratio, walker_force_lb, limit_ratio, ap_over_g
- Occupancy limits ao/g = 0.5% office/residence, 1.5% mall; P0 ~ 65 lb office walkerAISC DG11
- Resonant band low-frequency floors ~4-8 Hz resonate with the walking harmonic (e^(-0.35 fn) term)AISC DG11