Development of a Hybrid Base Isolation-Tuned Mass Damper Inerter System (BI-TMDI) for Seismic Protection of Steel Structures

In this conference paper, the performance of a hybrid base isolation-tuned mass damper inerter (BI-TMDI) system for seismic protection of steel structures was examined. It is anticipated that the displacement concentration issue at the base isolation floor which is characterized in the literature can be solved by using a TMDI. Firstly, the notion and configuration of the novel system were introduced. In particular, the BI was made of rubber bearings equipped with steel plates. To ensure the load carrying performance of the hybrid bearings, compression tests of the prototype specimens were conducted to examine the static loading carrying performance of the bearing. Subsequently, finite element model (FEM) of specimens were developed to reproduce the behaviour of the specimens. The reasonable correlation between the test results and numerical data confirmed the adequacy of the modelling technique. Based on the verified numerical modelling, a parametric study was further carried out to examine the static stiffness of the bearing and the influential parameters, and design recommendations were proposed. To confirm the rationality of the proposed bearing system, a prototype steel structure based on multi-degree-of-freedom (MDOF) analogy was developed, and the hybrid BI-TMDI was installed in the structure. The potential of the proposed system was confirmed by nonlinear dynamic analysis subjected to earthquake motions.