Development of a 10-element Hybrid Simulation Platform and its Application to Seismic Performance Assessment of Multi-storey Braced Frames

This study presents a 10-element hybrid (experimental-numerical) simulation platform, referred to as UT10, which was developed for running pseudo-dynamic hybrid simulations of braced frames with up to 10 large-capacity physical brace specimens. This study presents the details of the development of different components of UT10 including a network interface for actuator controller, NICON-10. An adjustable brace specimen, referred to as Adjustable Yielding Brace (AYB), was designed to simulate the hysteretic response of yielding braces such as buckling-restrained braces (BRBs) thus facilitating the seismic performance evaluation of multi-storey structures with hysteretic energy dissipative braces through hybrid simulations. Also, a buckling specimen was designed to simulate the hysteretic response of conventional buckling braces. Both AYB and buckling specimens were cyclically tested in UT10. The results indicated that these specimens are capable of producing hysteretic responses with characteristics similar to BRBs and conventional braces. A five-storey buckling-restrained braced frame (BRBF) and a special concentrically braced frame (SCBF) were designed and tested, respectively, with AYB specimens and buckling specimens representing the braces. Cyclic tests of the AYB and buckling specimens, 1- and 3-element hybrid simulations of the BRBF, and 2- and 4-element hybrid simulations of the SCBF inside UT10 confirmed the functionality of UT10 for running hybrid simulations on multiple specimens. Comparison of the results of the hybrid simulations of the BRBF and SCBF with their fully numerical models showed that the modelling inaccuracies of the yielding braces could affect the global response of the multi-storey braced frames further emphasizing the need for experimental calibration or hybrid simulation for achieving more accurate response predictions. UT10 provides a simple and reconfigurable platform that can be used to achieve a realistic understanding of the seismic response of multi-storey frames with yielding braces, distinguish their modelling limitations, and improve different modelling techniques available for their seismic response prediction.Ph.D