Grade beams for column bases in high sesimic zone

[dtcconeng]

We are involved in a building design that is located in SDC "D". We intend to utilize a flat plate system (due to owner requirements) with cast in place shear walls for our lateral system. Our intention is to size our shear walls so we can consider the columns "non sway". We haven't designed in a high seismic zone in the past and wanted to confirm whether it is necessary to provide grade beams at the base of each column to tie them togteher in order to prevent differential settlement and differential horizontal movement? Thanks in advance for any input provided.

 

[WillisV]

Yes.

 

[Taro]

Not necessarily. See IBC 1805.4.2.2. It depends on site class. Also, equivalent restraint provided by slabs can be considered. The project geotechnical consultant (if there is one) should also be consulted.