We explore nonlinear site effects in the new Japanese ground‐motion dataset compiled by Bahrampouri et al. (2020). Following the approach of Seyhan and Stewart (2014), we evaluate the decrease of soil amplification according to the increasing and corresponding ground motion on surface rock (⁠VS30=760 m/s⁠). To better predict the rock ground motion associated with each record, we take into account the between‐event variability of the ground motion, and to better evaluate the impact of nonlinearity, we correct observed ground motion on soil by the site‐specific linear amplification. Instead of grouping the stations by site‐response proxy, we focus on individual stations with several strong‐motion records. We develop a framework to test recently published nonlinear site amplification models against a linear site amplification model and compare the results with recent building codes that include nonlinearity. The results show that the site response varies greatly from site to site, indicating that conventional site proxies, such as VS30⁠, are not sufficient to characterize nonlinear site response. Out of all of the Kiban–Kyoshin network stations, 20 stations are selected as having recorded sufficient data to be used in the test. Out of these 20 stations, five stations show signs of nonlinearity, that is, the nonlinear models performed better than the linear‐amplification model for all periods T⁠. For most sites, however, the linear site amplification models get the best score. This suggest that, for the range of predicted rock motion considered in this study (peak ground acceleration <0.2g⁠), nonlinearity may not have a sufficiently large impact on soil ground motion to justify the use of nonlinear site terms in ground‐motion functional forms and seismic building codes for such moderate‐level shaking.

中文翻译：

---

测试地面运动模型的非线性放大系数

我们在 Bahrampouri 等人编制的新日本地面运动数据集中探索非线性场地效应。(2020)。遵循 Seyhan 和 Stewart (2014) 的方法，我们根据表层岩石上增加和相应的地面运动 (⁠VS30=760 m/s⁠) 评估土壤放大的减少。为了更好地预测与每个记录相关的岩石地震动，我们考虑了地震动的事件间变异性，并为了更好地评估非线性的影响，我们通过特定地点的线性放大来校正观测到的地震动对土壤的影响。我们不是通过站点响应代理对站点进行分组，而是关注具有多个强运动记录的单个站点。我们开发了一个框架来根据线性场地放大模型测试最近发布的非线性场地放大模型，并将结果与​​最近包含非线性的建筑规范进行比较。结果表明，站点响应因站点而异，这表明传统的站点代理，例如 VS30，不足以表征非线性站点响应。在所有 Kiban-Kyoshin 网络台站中，选择 20 个台站记录足够用于测试的数据。在这 20 个台站中，有 5 个台站显示出非线性迹象，即非线性模型在所有周期 T 内的表现都优于线性放大模型。然而，对于大多数站点，线性站点放大模型获得了最好的分数。这表明，