I’m working with opensees Navigator to model a 3D RC frame structure for non-linear analysis considering
1.Which material type shall I select from the drop down list of the uni axial material for the panel zone and for the interface bond slip?
2.can I assign the beam column element by Loweis and Altonash (2004) in which it has been formulated for 2D RC frames? 
3.and if you have any detailed manual of this software platform please attach me through Tewodrosh84@gmail.com, Last thing I want to ask you is if you guys know any formula to evaluate a RC beam column joint stiffness considering the above three parameters please contact me as soon as you can.