Seismic performance of optimal Multi-Tuned Liquid Column Damper-Inerter (MTLCDI) applied to adjacent high-rise buildings

Conventional vibration absorbers, e.g., a classical tuned mass damper, may be not efficient in simultaneously controlling the seismic response of adjacent high-rise buildings. In this paper, a novel passive vibration control system, denoted as Multi-Tuned Liquid Column Damper-Inerter (MTLCDI), is developed to control the seismic response of adjacent high-rise buildings. Two different configurations of this system, namely inter-story MTLCDI (IS-MTLCDI) and inter-building MTLCDI (IB-MTLCDI), are proposed, and related mathematical models are developed to investigate the seismic performance of MTLCDI. A case study project comprising two adjacent high-rise buildings equipped with the proposed system and subjected to ten earthquake records with various frequency characteristics is considered. Performance-based parametric optimization of the MTLCDI systems is performed through two distinct constrained multi-objective optimization problems via genetic algorithms, wherein peak absolute accelerations and inter-story drift ratios of the two adjacent buildings are selected as performance indexes. The mitigation effects of optimum IS-MTLCDI and IB-MTLCDI on earthquake-induced vibrations are scrutinized, with emphasis placed on the effects of natural frequency ratios between the two host structures. The results indicate that, when the two buildings have distinct natural frequencies, both IS-MTLCDI and IB-MTLCDI outperform inter-building single TLCDI as well as other vibration absorbers in terms of seismic vibration control of absolute acceleration and inter-story drift ratios. Under most natural frequency ratios, the IS-MTLCDI achieves a larger response reduction than IB-MTLCDI. Nevertheless, when the differences between natural frequencies of adjacent buildings are significant, applying an IB-MTLCDI may be preferable due to its satisfactory mitigation effects combined with ease of installation.