کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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507279 | 865111 | 2014 | 8 صفحه PDF | دانلود رایگان |
Elastic lattice methods (ELMs) have been shown to accurately model seismic wave propagation in a heterogeneous medium. These methods represent an elastic solid as a series of interconnected springs arranged on a lattice and recover a continuum wave equation in the long wavelength limit. However, in the case of a regular lattice, the recovery of the continuum equation depends on the symmetry of the lattice. By removing particles above a free surface this symmetry is broken. Therefore, this free surface implementation leads to errors when compared with a traction free boundary condition. The error between a traction free boundary condition and the ELMs grows as the Poisson׳s ratio deviates from 0.25. By modifying the interaction constants with a scalar, the error can be reduced while keeping the flexibility of the nearest neighbour interaction rule. We present results of simulations where modified spring constants reduce the misfit with a traction free boundary solution and hence increase the accuracy of the elastic lattice method solution on the free surface.
Journal: Computers & Geosciences - Volume 67, June 2014, Pages 117–124