Most elevator vibration problems are typically attributed to common causes such as machine misalignment, worn bearings, rope imbalance, guide rail issues, or improper installation.
However, there are situations where all conventional checks are carried out and the vibration problem still persists.
In such cases, engineers may need to look beyond routine troubleshooting and consider a less common phenomenon: Resonance.
Every physical object possesses a natural frequency at which it tends to vibrate.
When an external force repeatedly acts on the object at a frequency matching its natural frequency, the vibration amplitude increases significantly. This phenomenon is known as resonance.
A well-known example is found in military practice.
When soldiers cross a bridge, they are often instructed to break their marching rhythm ("Kadam Tod").
The reason is simple.
The rhythmic footsteps of a marching group generate cyclic forces. If the frequency of those forces matches the natural frequency of the bridge structure, resonance may occur, causing excessive oscillation and potentially damaging the bridge.
This principle applies not only to bridges but also to buildings, machinery, vehicles, and elevator systems.
Elevator installations consist of multiple components capable of vibration, including:
Each component has its own natural frequency.