Hierarchical Simulations and Seismic Performance Evaluation of Tall Buildings Equipped with Negative Stiffness Damped Outrigger with Damping Amplification

To address the damping limitations of conventional damped outrigger (CDO) systems in tall buildings and reduce the damping force demand of viscous damper installed at the outrigger end, a novel negative stiffness damped outrigger with damping amplification (NSDO-DA) has been developed, fabricated, and dynamically tested. The results demonstrated its ability to generate an adaptive negative stiffness effect and enhanced damping performance. This paper presents a hierarchical numerical simulation of the NSDO-DA system, spanning from its key component to its application in tall buildings, using a detailed finite element model. Specifically, the key components, including disk spring pairs and disk spring brace (DSB), were modeled and validated against cyclic test results. Furthermore, numerical finite-element models of three outrigger systems—pure negative stiffness mechanism (NS), negative stiffness damped outrigger (NSDO), and NSDO-DA—were developed using three-dimensional (3D) solid elements. These models were validated through dynamic test results and employed for a parametric study to overcome the limitations of testing facilities and theoretical assumptions. Finally, the seismic performance of tall buildings incorporating the NSDO-DA system was assessed through simulations of a 50-story tall building example.