We present correlation coefficient estimates between a number of ground motion intensity measures (IMs), as measured from the NGA-West2 database, with focus on the correlation of vertical–vertical and vertical–horizontal ground motion components. The IMs considered include spectral accelerations with periods from 0.01 to 10 s, peak ground acceleration, peak ground velocity, and significant duration (for 5%–75% and 5%–95% definitions). To facilitate their use, parametric equations are also fitted to the correlation models. Finally, the dependence of the obtained correlation coefficients to magnitude, distance, and Vs30 is evaluated.

中文翻译：

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垂直和水平地震动对的谱加速度值的相关性

我们提出了许多地震动强度测量 (IM) 之间的相关系数估计，如从 NGA-West2 数据库测量的，重点是垂直-垂直和垂直-水平地震动分量的相关性。考虑的 IM 包括周期为 0.01 到 10 s 的频谱加速度、峰值地面加速度、峰值地面速度和显着持续时间（对于 5%–75% 和 5%–95% 的定义）。为了方便它们的使用，参数方程也适用于相关模型。最后，评估获得的相关系数对幅度、距离和 Vs30 的依赖性。