建物の基礎免震，中間層免震および同調型マスダンパによる制振の統一的理解

Abstract

For a building with an interstory seismic isolation system, an inverse problem is formulated based on the pole allocation method in control theories. The structural system is simplified as a 3DOF lumped-mass shear model. The natural frequencies and the corresponding damping ratios in the three vibration modes are set as the initial control target. To achieve this target, the introduced solution provides the natural frequencies of the lower substructure, upper substructure, and the isolator with damper capacity. The closed-form expression clarifies how the isolator's natural frequency and damper's capacity are related to the dominant natural frequencies of both the substructures and to the target modal damping ratios. The mathematical expression explains the trade-off relationship between the damping ratios of the lower and upper substructures. The solution is also applied to a building with a base seismic isolation system or a tuned mass damper system.