A high performance hybrid passive base‐isolated system

Abstract

This paper proposes a novel high performance hybrid passive base-isolated system integrating the base-isolated system (BIS) with the tuned tandem mass damper inerters (TTMDI), referred to as the BIS+TTMDI. To reveal the interaction between two components and their integrated control performance, the proposed configuration is modeled by a simplified four degree-of-freedom model together taking the dynamic characteristics of the isolation system, TTMDI, and superstructure into inclusion. Employing the optimization criterion defined as minimization of the dimensionless variance of superstructure displacement relative to the ground and by resorting to the particle swarm optimization, the system parameters of TTMDI are tuned to get their best integrated control performance. Evaluations are in turn unfolded on the performance taking into diverse TTMDI inertial properties and different isolation layer characteristics account and robustness, to fully explore the effectiveness of reducing both the displacement and acceleration for the isolation layer and superstructure, the TTMDI's energy dissipation mechanism and capacity, evolution of stiffness and damping, stroke, and structural frequency response. Subsequently, the findings of the BIS+TTMDI in the frequency domain is further tested via the time history analyses using the real records including both near-field with pulse and far-field earthquakes. In two analysis domains, the integrated performance of the proposed BIS+TTMDI is compared not only to the BIS but also to the BIS+TMDI, as well as to the BIS+TTMD and BIS +TMD. Results confirm that the BIS+TTMDI is a high performance system, namely, with high control effectiveness, high robustness, highly smaller stroke, and drastically reduced damping demand.

Effects of geometric nonlinearities on the vibration reduction performance of tuned mass dampers on top of flexible structures

“…Tuned mass dampers (TMDs) have been shown effective in reducing the dynamic response of structures (Cao and Li, 2019, 2022; Elias and Matsagar, 2017; Housner et al, 1997; Soong and Costantinou, 1994; Soong and Spencer, 2002; Wang et al, 2019, 2021). They have been increasingly used in the vibration control of flexible structures of large aspect ratios, like tall buildings, bridge towers, and wind towers under either strong winds or earthquakes (Figure 1).…”

Stochastic Optimization of a Nonlinear Base Isolation System with LRB and EIMD for Building Structures

“…Although the original structure response is greatly reduced, a large deformation induced by the earthquake ground motion will occur on the base foor, thus the superstructure might face collapse risk when experiencing an extremely rare earthquake. Hence, hybrid base isolation systems, which combine isolation bearings and passive dampers, receive increasing attention [7][8][9][10][11] and intend to tackle the challenges of overlarge base deformation of the BIS during extremely rare earthquakes while maintaining or reducing superstructure responses.…”

Numerical studies on the seismic responses of precast segmental columns-supported bridge structures subjected to near-fault ground motions

“…permanent displacement) can be found in the velocity and displacement time histories, respectively (Abrahamson, 2001). Due to the different rupture mechanisms, these two types of pulse can induce different structural responses, and some researchers discussed the influences of both types of pulses on the seismic responses of buildings (Bhagat et al, 2021; Li et al, 2021; Vafaei and Eskandari, 2015), continuous bridges (Cao and Li, 2022; Chen and Li, 2021), concrete-filled steel tubular arch bridges (Xin et al, 2019), steel-concrete composite rigid-frame bridges (Lin et al, 2020a; 2020b), cable-stayed bridges (Li et al, 2017), intake tower structures (Chen et al, 2020), etc. However, to the authors' best knowledge, no open literature explicitly discusses the impact of different types of N-F pulse on the seismic responses of segmental columns-supported bridges.…”