Site Response Analysis: Blind Deconvolution of Seismic Signals and Site Characteristics Using Data Fusion and Higher-Order Cepstra Operations

9319829 PetroPulu通过理论和观测表明，与基岩上记录的条件相比，已建设施现场的条件可以显著放大地震地面运动。这种放大增加了工程结构的潜在损伤和倒塌。这项研究的目的是检验将盲解卷积算法应用于场地响应分析的可行性，并调查该方法是否能够更好地理解这一问题背后的复杂现象。该方法利用盲解卷积算法和沉积场地上两个台站的地面运动记录来重建基岩界面处的地震输入，并通过输入位置和记录站点之间的脉冲响应(反射率)来恢复场地的特征。通过结合地震记录的高阶统计量和仅从高阶谱相位重建信号的理论来估计场地特征。与现有技术相比，这种方法的潜在优势是：(I)它不需要在附近岩石场地的记录或用于特定场地分析的井下记录，而是根据两个地面记录重建沉积物底部的地震输入运动；(Ii)它识别基岩层界面和每个记录站之间的反射率，而不是来自井下(或附近岩石)站和沉积物场地表面上的一个站的一维场地响应函数；以及(Iii)即使在观测和沉积物底部的输入地震运动中存在加性高斯白噪声的情况下，该方法仍然保持稳健。这项探索性研究集中在台湾SMART-1加速度计台阵记录良好的地震。***

9319829 Petropulu It has been shown, through theory and observations, that conditions at the site of a constructed facility can amplify the seismic ground motions significantly, as compared to those recorded on bedrock. This amplification increases the potential damage and collapse of engineered structures. The objective of this research is to examine the feasibility of applying a blind deconvolution algorithm to site response analysis; and to investigate whether the approach can lead to a better understanding of the complex phenomena underlying this problem. The approach utilizes the blind deconvolution algorithm and the recordings of ground motions at two stations on a sediment site in order to reconstruct the seismic input at the bedrock-layer interface and to recover the characteristics of the site through impulse responses (reflectivities) between the input location and the recording stations. The site characteristics are estimated by combining higher-order statistics of the seismograms and the theory of signal reconstruction from higher-order spectral phase only. Potential advantages of this approach over existing techniques are that (i) it does not require recordings at nearby rock sites or downhole recordings for the site- specific analysis, but reconstructs the seismic input motion at the base of the sediments from two surface records; (ii) it identifies the reflectivities between the bedrock-layer interface and each recording station rather than one one- dimensional site response function from the downhole (or nearby rock) station and one station on the surface of the sediment site; and (iii) it remains robust even in the presence of additive white Gaussian noise in the observations and in the input seismic motion at the base of the sediments. This exploratory study concentrates on well documented earthquakes recorded by the SMART-1 accelerograph array in Taiwan. ***