MULTI-ELEMENT HYBRID SIMULATIONS ON STEEL STRUCTURES: ADVANCEMENTS, CHALLENGES, AND LESSONS LEARNED

Substructuring pseudo-dynamic hybrid simulation (PsDHS) is an efficient, yet effective testing method for evaluating the system-level response of structures under extreme loading scenarios. In PsDHS, the response of the critical structural components is captured in a laboratory through physical testing and is integrated with the numerical response of the remainder of the structure in a numerical model, by establishing a communication framework between the two. The former is referred to as a physical substructure and the latter is often referred to as the integration module. Despite its widespread applications and significant advancements, a commonly recognized constraint with substructuring PsDHS is the limited number of physical substructures that can be included in experiments. In an attempt to increase the number of physical substructures in PsDHSs, the University of Toronto Ten Element Hybrid Simulation Platform (UT10) was recently developed. The UT10 is capable of testing up to ten uniaxial rate-independent physical substructures simultaneously, and since its development has been used in several projects for the performance assessment of ductile steel structures such as buckling restrained braced frames, special concentrically braced frames, yielding brace systems with cast steel yielding connectors, and more recently, a controlled rocking steel structure. This paper provides an overview of the UT10, its features, and past research projects featuring multielement hybrid simulations using the UT10. Challenges, lessons learned, and conclusions from each multielement hybrid simulation are presented, along with visions for future research directions.