For modeling BRB in Sap 2000 software, first of all you should model the structure in Etabs 2016 which has StarseismicBRB sections. Then using this prepared sections, you can model BRBs in Sap 2000 using "Link properties".
You can model the BRB in SAP2000 by calculating the equivalent area of BRB. Nonlinear properties of BRB are entirely concentrated in plastic hinge. So the backbone curve of BRB element can be obtained from ASCE 41, or from experimental results The plastic hinge should be assigned at middle.