Micromechanics of seismic wave propagation in granular materials
Micromechanics of seismic wave propagation in granular materials
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DOI：
10.1007/s10035-015-0599-4
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发表时间：
2016-08
期刊：
影响因子：
2.4
通讯作者：
J. O’Donovan;S. Hamlin;G. Marketos;Catherine O'Sullivan;E. Ibraim;ML Lings;D. M. Wood
中科院分区：
文献类型：
--
作者：
J. O’Donovan;S. Hamlin;G. Marketos;Catherine O'Sullivan;E. Ibraim;ML Lings;D. M. Wood
在这项研究中，在一个立方体细胞模型土壤的实验数据进行了比较，离散元（DEM）模拟和连续分析。实验和模拟使用点源发射器和接收器来评估样品的剪切波和压缩波速度，从中可以推导出一些弹性模量。在实验中的弯曲器/扩展器压电陶瓷元件所产生的扰动的复杂响应进行了比较，发现在DEM模拟的颗粒的受控运动。一般令人满意的协议之间的实验观察和DEM模拟可以被看作是一个验证和支持使用DEM来调查谷物相互作用对波传播的影响。考虑了插入信号的较高频率分量的滤波、频域中输入和接收信号的比率以及样本谐振的频域分析提供了对系统响应的有用洞察。立方体振动的频域分析和连续解析解表明，测试配置激发了系统的一些，但不是全部的共振频率。DEM提供的颗粒尺度数据使波传播过程中的能量耗散分析成为可能。在颗粒尺度上的频域分析表明，较高的频率含量随着距离激发点的增加而减少。
In this study experimental data on a model soil in a cubical cell are compared with both discrete element (DEM) simulations and continuum analyses. The experiments and simulations used point source transmitters and receivers to evaluate the shear and compression wave velocities of the samples, from which some of the elastic moduli can be deduced. Complex responses to perturbations generated by the bender/extender piezoceramic elements in the experiments were compared to those found by the controlled movement of the particles in the DEM simulations. The generally satisfactory agreement between experimental observations and DEM simulations can be seen as a validation and support the use of DEM to investigate the influence of grain interaction on wave propagation. Frequency domain analyses that considered filtering of the higher frequency components of the inserted signal, the ratio of the input and received signals in the frequency domain and sample resonance provided useful insight into the system response. Frequency domain analysis and analytical continuum solutions for cube vibration show that the testing configuration excited some, but not all, of the system’s resonant frequencies. The particle scale data available from DEM enabled analysis of the energy dissipation during propagation of the wave. Frequency domain analysis at the particle scale revealed that the higher frequency content reduces with increasing distance from the point of excitation.