Moorthi,

CAESAR II or that way any software related to Applied Mechanics cannot violate the fundamental principles of Mechanics. If the modelling has been made correctly, then wt. of the expansion joint is a must input in the model and if the nozzle takes wt, then that is it.

I feel what you need to do is to see the global element report and see why the nozzle is taking load. This is as per the principle of equilibrium and distribution of loads between elements of different stiffneses ( method of moment distribution).If you yourself can justify why the load is coming to the nozzle ( which I am sure you will, once you carefully look into this report), why you need to ask the vendor or anybody ?

In response to John's reply, I would like to add that Indian culture has never produced expansion joints of zero wt, but yes, many of us don't like to delve into fundamentals of mechanics
and hence puts such questions.

Regards