Capacity Spectrum–based Seismic Response Prediction of Vibration-Controlled Ceiling Structures Employed Pulley Mechanisms

One of the most widely used practical structural analysis approaches to evaluate the maximum seismic response of structures is the capacity spectrum method (CSM). Based on the CSM, this paper presents a new procedure for predicting the structural response of passively controlled suspended ceiling structures named “Pulley Damper Ceiling System (PDCS)” based on the CSM. The PDCS employs the displacement amplification mechanism of a block and tackle pulley system, and the supplemental damping element comprises a rotary damper and a friction damper. The single-degree-of-freedom model of the PDCS is initially constructed. Then the reliability of the simplified calculation to obtain an equivalent damping coefficient of the PDCS, which is determined by the sum of the inherent damping and the square root of the sum of squares of each damping provided by the nonlinear viscous damper and the bilinear hysteretic damper, is validated by comparison with the full-scale shake table test results of the PDCS. In this study, the capacity curve of the system was generated by continuously plotting the transition of maximum force and displacement values under different amplitudes of sinusoidal waves. Finally, the availability of the proposed CSM to predict the peak response during earthquake excitations was assessed by comparing it with results from time history analyses. In addition, because the target structure of the PDCS is suspended ceilings, the floor response spectrum was also examined, and accuracy sufficient to evaluate the seismic response was confirmed.