How much sideways force does an earthquake put on a building? The equivalent lateral force method boils it down to a base shear and spreads it up the floors.
Seismic Base ShearLive
equivalent lateral force
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The equivalent lateral force method estimates the total earthquake base shear as V = Cs·W, where the seismic coefficient Cs scales the design acceleration by the structure's ductility (R) and importance (I). The base shear is distributed up the building, concentrating force at the top. Educational tool, not a code design.
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How it works
The equivalent lateral force procedure estimates total seismic base shear as V = Cs·W, where the seismic response coefficient Cs scales the design spectral acceleration by the structure's ductility factor R and importance factor I. The base shear is then distributed up the height, concentrating demand near the roof. Educational tool, not a code design.
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