Seismic inversion of soil damping and stiffness using multichannel analysis of surface wave measurements in the marine environment
Seismic inversion of soil damping and stiffness using multichannel analysis of surface wave measurements in the marine environment
复制标题
使用海洋环境中表面波测量的多通道分析来反演土壤阻尼和刚度的地震
DOI：
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复制
发表时间：
2020
影响因子：
2.8
通讯作者：
K. V. Dalen
中科院分区：
文献类型：
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作者：
M. Armstrong;M. Ravasio;W. G. Versteijlen;D. Verschuur;A. Metrikine;K. V. Dalen
土壤材料阻尼的确定是困难和不确定的，特别是在近海环境中。使用先进的反演方法的基础上，多通道频谱分析，Scholte和爱波测量用于表征海底土壤从北海网站。归一化后，基于行列式的目标函数被用于遗传算法优化，以估计土壤剪切模量。倒置的剪切模量配置文件是以前公布的结果相同的数据，虽然更高程度的确定性是在近地表层实现。采用半功率带宽法提取衰减曲线，并基于小波压缩选择有效的参考数据点。材料阻尼比反演是使用一种改进的随机优化算法。考虑到测量误差，从基模Scholte波中获得了具有高度确定性的材料阻尼比分布。此外，提出了一种方法，用于识别的材料阻尼比的频率依赖性从现场测量。没有发现频率依赖性的证据，并且可以说，在该场地的小应变土壤材料阻尼比与测量条件的频率无关。
Determination of soil material damping is known to be difficult and uncertain, especially in the offshore environment. Using an advanced inversion methodology based on multichannel spectral analysis, Scholte and Love wave measurements are used to characterize subsea soil from a North Sea site. After normalization, a determinant-based objective function is used in a genetic algorithm optimization to estimate the soil shear modulus. The inverted shear-modulus profile is comparable to previously published results for the same data, although a higher degree of certainty is achieved in the near-surface layers. The half-power bandwidth method is used for extracting the attenuation curve from the measurements and efficient reference data points are chosen based on wavelet compression. The material-damping ratio inversion is performed using a modified stochastic optimization algorithm. Accounting for measurement errors, the material-damping ratio profile is retrieved from the fundamental-mode Scholte wave with a high degree of certainty. Furthermore, a method is proposed for identifying the frequency dependence of the material-damping ratio from in situ measurements. No evidence for frequency dependence is found and the small-strain soil material-damping ratio at this site can be said to be frequency independent for the measured conditions.