Common procedures used to account for spatial variability of shear wave velocity (Vs) in one-dimensional (1D) ground response analyses (GRAs), such as stochastic randomization of Vs or increasing small-strain damping, have been shown to improve seismic site response predictions relative to 1D GRAs where no attempts are made to account for spatial variability. However, even after attempting to account for spatial variability using common procedures, 1D GRAs often still yield results that are different than ground motions recorded at many downhole array sites. When 1D predictions differ from observations, the site is typically considered to be too spatially variable to effectively use 1D GRAs. While there is no doubt that some sites are indeed too variable for 1D GRAs, it is also possible that simple 1D analyses could still be effectively used at many sites if spatial variability is accounted for through a more rational, site-specific approach. In this study, an H/V geostatistical approach for building pseudo-3D Vs models is implemented to account for spatial variability in 1D GRAs. The geostatistical approach is used to generate a uniform grid of Vs profiles that have been scaled to match fundamental site frequency estimates from horizontal-to-vertical spectral ratio (H/V) noise measurements. In this article, 1D GRAs are performed for each grid point and the results are statistically combined to reflect the average site response and its variability. This 1D application is demonstrated at the Treasure Island and Delaney Park Downhole Array sites, where it is shown to produce superior fits to the small-strain recorded site response relative to existing approaches used to account for spatial variability in 1D GRAs. Using the proposed approach, we also investigate the lateral area that is likely influencing site response at each site and show that it could extend to significant distances (as much as 1 km) from the boreholes.

一维（1D）地面响应分析（GRAs）中用于解释剪切波速度（Vs）空间变异性的通用程序，例如，Vs的随机随机化或增加小应变阻尼，已被证明可以改善地震现场的响应。相对于1D GRA的预测，其中未尝试考虑空间变异性。但是，即使在尝试使用通用程序解决空间变异性之后，一维GRA仍然经常产生与在许多井下阵列位置记录的地面运动不同的结果。当1D预测与观测值不同时，通常认为该站点的空间变化太大，无法有效使用1D GRA。毫无疑问，对于一维GRA，某些站点确实存在很大差异，如果通过更合理的，针对特定地点的方法来考虑空间变异性，那么仍然有可能在许多地点仍可以有效地使用简单的一维分析。在这项研究中，H / V地统计学方法可用于构建伪3D Vs模型，以解决1D GRA中的空间变异性。地统计方法用于生成Vs轮廓的统一网格，已对其进行缩放以匹配水平/垂直频谱比（H / V）噪声测量中的基本站点频率估计。在本文中，对每个网格点执行一维GRA，并将结果统计合并以反映平均站点响应及其变异性。在金银岛和德莱尼公园井下阵列现场演示了此一维应用程序，相对于用于解决一维GRA中空间变异性的现有方法，该方法对小应变记录的现场响应具有更好的拟合度。使用提出的方法，我们还研究了可能影响每个站点的站点响应的横向区域，并显示该区域可能会延伸到距井眼很远的距离（多达1公里）。