Strange results core walls

[Anonymous]

Hi

I am doing seismic  analyses on a concrete building. I have defined stories and core walls. 

When I apply the  self weigth of the structures only  I got Fx and Fy forces in the core walls and the supports.

The same happens  if I apply the live load or snow separately.

I did not expect to get any horisontal forces since the self weight, live load or snow are vertical forces.

Is this correct? Does anyone have a solution?

[Rafal.Gaweda]

Simple example - look at forces, shear force diagram, FX reactions.