Seismic force distribution on silo
Seismic force distribution on silo
(OP)
I'm not sure how to distribute the base shear along the length of a silo. For determining the overturning moment, does the base shear on a silo (contained mat'l is lime) act at the centroid of the structure?





RE: Seismic force distribution on silo
If this silo rests on ground say, then conservative case is to assume seismic load as an inverted triangular distributed force (static equivalent). Thus CoG effetively at 2/3 height. This is the classical first mode response of an elastic vertical beam of uniform mass. It may be too conservative, depending on whether you are dealing with a 'deep' silo or 'shallow' silo.
If the silo is on legs then the response will be different. In this case I would probably assume seismic force acts at the real CoG.