An improved approximation for the spectral representation method in the simulation of spatially varying ground motions

详细信息	查看全文 | 推荐本文 |

• 作者：Yufeng Gao^a ; ^{yfgao@hhu.edu.cn} ; Yongxin Wu^a ; ¹ ; ^{yongxinwuhhu@yahoo.com.cn} ; Dayong Li^b ; ² ; ^{ldy@sdust.edu.cn} ; Hanlong Liu^a ; ³ ; ^{hliuhhu@163.com} ; Ning Zhang^a ; ¹ ; ^{240401zn@163.com}
• 关键词：Ground motions simulation ; Spectral representation method ; Spatially varying ; Approximation
• 刊名：Probabilistic Engineering Mechanics
• 出版年：2012
• 期刊代码：146_02668920
• 类别：et
• 出版时间：July, 2012
• 卷：29
• 期：Complete
• 页码：7-15
• 文件大小：1025 K

摘要

The spectral representation method (SRM), based on the Cholesky decomposition of either cross spectral density matrix or lagged coherency matrix, is widely used in the simulation of spatially varying ground motions. In this study, the SRM, based on the decomposition of lagged coherency matrix, is modified to apply to the common case which the auto spectral densities of simulation points are not the same. When using interpolation approximation approach to improve the efficiency, the SRM based on the decomposition of lagged coherency matrix exhibits much higher accuracy than the SRM based on the decomposition of cross spectral density matrix, because the elements of lower triangular matrix obtained by the Cholesky decomposition of lagged coherency matrix vary slowly with the frequency. Therefore, the SRM, based on the decomposition of lagged coherency matrix, is generally suitable for the combination with the interpolation approximation approach.