Defining nonlinear hinges for pipe sections??

[larsson]

hi ppl. currently im working on a static pushover analysis for an offshore platform carried by steel pipe columns. but im in the verge of blowing my head off cuz i just couldnt find a way to define plastic hinges for these sections for months. i found out that etabs is capable of defining auto hinges for steel pipe sections but it has so less options in detail so i cant trust these hinges created. im trying to transfer these data from etabs to sap2000 manually but im having problems in defining the moment-rotation curve data for several axial loads to obtain best results. as you can understand trying to generate a brand new hinge is a lot of work and has so much details to cope with. is there any way of defining these hinges automatically with some kind of program? any theoretical suggestions and advices on generating this hinge manually will also be appreciated...