Elastoplastic model for response and response sensitivity analysis of metallic dissipative devices and implementation in OpenSees

An elastoplastic model for metallic hysteretic dissipative devices allowing a straightforward physical interpretation of the constitutive parameters of the model, explicit computation of response quantities related to failure and dissipated energy, is implemented into OpenSees. The implemented algorithms include response and consistent response sensitivity results to the constitutive model parameters. Specifically, response sensitivity results are obtained through the direct differentiation method (DDM) and their derivation and implementation validated through the forward finite difference method (FDM). Selected results response sensitivity analysis and a simulated model updating problem are illustrated and discussed using as a case study a realistic multi-storey steel frame with BRBs subjected to a set of seismic accelerations.