A new fast multi‐domain BEM to model seismic wave propagation and amplification in 3‐D geological structures
A new fast multi‐domain BEM to model seismic wave propagation and amplification in 3‐D geological structures
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DOI：
10.1111/j.1365-246x.2008.04041.x
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发表时间：
2009-05
影响因子：
2.8
通讯作者：
S. Chaillat;M. Bonnet;J. Semblat
中科院分区：
文献类型：
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作者：
S. Chaillat;M. Bonnet;J. Semblat
地震波在复杂地质结构中传播和放大的分析需要高效和精确的数值方法。传统的边界元法（BEM）的弹性动力学方程的解决方案，极大地阻碍了由离散所产生的矩阵方程的完全填充的性质。在以前的研究限于均匀介质中，本作者已经建立了快速多极子方法（FMM）的3-D弹性动力学边界元法的复杂性降低到N日志N每GMRES迭代，并证明其有效性3-D峡谷配置。本文将频域FM-BEM方法推广到三维弹性波在分段均匀区域中的传播问题，提出了一种FM加速的多区域BE-BE耦合方法。这种新方法大大提高了边界元法研究地震波在半无限介质中任意几何形状的三维冲积盆地中传播的能力。几个完全三维的例子（斜SV波）代表这样的配置验证和演示的多域FM方法的能力。它们包括与可用的（低频）结果为各种类型的入射波场和时域结果通过傅立叶合成的比较。
SUMMARY The analysis of seismic wave propagation and amplification in complex geological structures raises the need for efficient and accurate numerical methods. The solution of the elastodynamic equations using traditional boundary element methods (BEMs) is greatly hindered by the fully-populated nature of the matrix equations arising from the discretization. In a previous study limited to homogeneous media, the present authors have established that the fast multipole method (FMM) reduces the complexity of a 3-D elastodynamic BEM to N log N per GMRES iteration and demonstrated its effectiveness on 3-D canyon configurations. In this paper, the frequency-domain FM-BEM methodology is extented to 3-D elastic wave propagation in piecewise homogeneous domains in the form of a FM-accelerated multi-region BE–BE coupling approach. This new method considerably enhances the capability of the BEM for studying the propagation of seismic waves in 3-D alluvial basins of arbitrary geometry embedded in semi-infinite media. Several fully 3-D examples (oblique SV -waves) representative of such configurations validate and demonstrate the capabilities of the multi-domain FM approach. They include comparisons with available (low-frequency) results for various types of incident wavefields and time-domain results obtained by means of Fourier synthesis.