Hybrid tests with buckling restrained braces for validating model updating with unscented Kalman filter

The whole structure is a frame structure incorporating two all-steel buckling-restrained braces (BRBs). One BRB is selected as physical substructure; the remainder of the structure is numerically modeled in the CPU of dSPACE real-time simulation system. The numerical integration of equation of motion and numerical model updating are also carried out in the dSPACE. Firstly, the displacement of experimental substructure is calculated in dSPACE and sent to the MTS testing system. The MTS controller receives it as a measurement signal and instantly sends it to the actuator to load the specimen to the target displacement. Then the measurements of reaction force and displacement are sent by the MTS back to dSPACE. With the experimental data, the parameters of hysteretic model are estimated and used to update the numerical BRB in the dSPACE. This completes one time step of numerical integration, physical loading and model updating, and these will be repeated until the end of the test.