Seismosoft | Earthquake Engineering Solutions

Hello,

I made a pushover analysis in seismobuild to a building with 2 underground floors and 8 main floors (I chose that option in the building modeller) but in the pushover analysis I noticed the underground floors recieved lateral forces for the combination I chose (no. 25 X +0.3Y) and even failed to the SD Limit State. I was expecting to only have forces in the main floors and not in the underground floors.

Is it normal to the program to apply lateral loads in the underground floors and even have failed members as walls?

BR,
Pedro Silva

Hi Pedro,

As Fanis must have explained, applying lateral incremental forces in the basement is a conservative, because there is no clear concensus between the Standards on how to deal with this issue. Regarding the failure of the basement walls, it is not unlikely to happen, especially in older constructions.
In any case, you could also ignore the basement and fix the building to the ground floor level.
Seismosoft Support