Characteristics of Higher-Mode Structural Responses under Pulse-Like Ground Motions

• Main Authors: Hsun-Chieh Chen, 陳勳傑
• Other Authors: Ching-Tung Huang
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/16057250459869097452

碩士 === 國立臺灣科技大學 === 營建工程系 === 89 === The main objective of this study is to investigate the characteristics of structural seismic demands under pulse-like ground motions in the near field. Considerations of analytical structural models are given to shear- beam and frame systems. The corresponding seismic base shear demands are evaluated for a set of artificial ground velocity pulse models. The study is separated into two parts. The first part is to evaluate the contribution of higher-mode responses under the pulse-like ground motions for the shear-beam and frame systems. For both systems, the study results indicate that higher-mode responses are significant for long-period structures. The second part is to investigate the applicability of the response spectral method for the near-field ground motions. The investigation is based on three modal summation approaches: the absolute sum(ABS), the square root of sum of the square(SRSS), and the complete quadratic combination(CQC). The resulting base shear demands are compared to the numerically exact solutions to determine the accuracy for each approximation approach. The study results reveal that the ground pulse shape is a major factor that dominates the accuracy of the response spectral method.