SEISMIC RESPONSE PREDICTION METHOD OF BASE ISOLATION STRUCTURES CONSIDERING COMPLEX EIGENVALUES

Proposal of Complex Eigenvalue Estimation Formula and Mode Synthesis Design Method

Abstract

This paper proposes a methodology that can accurately predict the overall response of base-isolated structures by leveraging eigenvalues (natural period, viscous damping constant), participation vectors, and bilinear hysteresis parameters (hysteresis damping constant, bilinear coefficient, ductility factor) derived from complex eigenvalue analysis. This analysis introduces estimating formulas for complex eigenvalues, which can be calculated using data obtained from elastic eigenvalue analysis.

As a result, it was found that complex eigenvalues could be estimated with high precision using the proposed estimating equation. Moreover, it was confirmed that the method provides high accuracy in predicting both response displacement and response acceleration.