How are the seismic loads computed?
The seismic loads are computed as horizontal static loads at the level of each floor. The vertical distribution of the seismic force is a reverse triangle. The total seismic force is (seismic coefficient)x(total vertical load). The seismic coefficient is defining the horizontal seismic acceleration, and can be changed from the first line of the yellow pad, or the menu Parameters/Initial values/Earthquake. The total seismic load is distributed to the walls taking into account the eccentricity of the seismic force. (offset of floor mass center from building elastic axis). The computed eccentricity is increased by a factor specified in the menu Parameters/Initial values/Earthquake/Increase of seismic eccentricity. (by default this factor is=1).
