static analysis - we have to model loads only on jacketed portion , on core elements, switch off uniform load vector - please advice

dynamic response - no such issue

any one - richard / dave / mandeep ? can yu help ?

I do not see a clear question here.

sorry, i did complicate the query.

in static seismic - i have put seismic in terms of g under U1,U2 as x=0.144 and z = 0.144 respectively for jacket nodes. For core nodes , do I need to change this U1 ,U2 to zero ? In my opinion "NO", because making it zero will take away the seismic effect due to core weight. One person from PMC argued that seismic effect will not be transferred to core as it is not connected to structure. It was explained to them that there is a connection between core and jacket hence the effect will be seen by both.
Wanted some reference to argue my opinion.Hence the query.
Regards,
bag_piper

Your static g load magnitude reflects (should reflect) the modification of the ground response provided by the structure between ground and piping. For example, the ASCE 7 horizontal acceleration for building components is a function relative vertical position of the component in the building [i.e., (1+2*(z/h))].
To say that the core "sees" no g load is incorrect. It may have a different acceleration (as modified by the jacket and it's core connections) but it will not be zero.