Edited on Mon Feb-21-05 03:31 PM by McKenzie
Older buildings have mass walls that carry the load of the roof and the walls throughout their depth. In effect, the entire wall is a structural element. Vibration is less damaging to these type of structures, unless the building has a large number of large window openings relative to the wall area. The wall has sufficient mass to absorb the vibes at lower floor levels.
Steel frames carry loads in a different way and vibrate up their entire height because the steelwork quivers. The walling is self-supporting and is usually isolated from the vibes.
The biggest risk is movement of the structure and cracking, regardless of the structural system. You'll notice if that happens; even a small amount of movement will crack window panes and doors will start to bind within their frames.
Big problem and difficult to prove. There are procedures that can be used to determine how the vibration waves move from the ground plane into the structure. Expensive and often inconclusive though.
edit: speling
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