Dear Ramesh,
Unfortunately......I did not modelled them in Caesar-II...as per the client requirements we were forced to use the other analysis software. In that we modelled the expansion joint as a axial one and ignore the pressure thrust forces (it was having some seetings to ignore the forces in the load cases).
But I will suggest you to first get the tentative drawings & stifness for pressure balance exp joint. I will look in to the back up if i found anything i will revert on your personal mail ID.

Regards,
R.K.