Enhanced seismic resilience of MSCSS using a novel hybrid VD-TFPB control system with consideration of soil-structure interaction

This study presents a novel seismic control system, the Mega-Sub Controlled Structure System (MSCSS), to address vibration control challenges in tall and super-tall buildings under intense seismic excitations. The proposed hybrid VD-TFPB-controlled MSCSS integrates Triple Friction Pendulum Bearings (TFPBs) as base isolators with Viscous Dampers (VDs) between the mega frame and the vibration control substructure, enhancing damping and seismic performance. MSCSS without VD and MSCSS with VD models are established and verified using an existing benchmark. The hybrid VD-TFPB-controlled MSCSS is then developed to evaluate its vibration control response while considering soil-structure interaction (SSI). Numerical analyses with earthquake records demonstrate its superior performance compared to MSCSS without and with VD systems. Nonlinear dynamic analyses reveal that the hybrid system significantly improves vibration control. However, under SSI, increased structural flexibility leads to higher frame stress and more plastic hinges, particularly on soft soil, which amplifies vibrations. Despite these challenges, the hybrid VD-TFPB-controlled MSCSS effectively enhances seismic resilience, offering a robust solution for tall buildings.