| 講演要旨(和文) | | 常時微動のH/Vスペクトルは，地盤の特性の把握に良く使用されている．今回，表層から砂礫地盤のサイトで，微動のH/Vの周期が約1秒を示すサイトがある例を示した．そのサイトで現れる周期が，レイリー波のR/VスペクトルやSH波の増幅度計算を用いて，ある基盤面からの1次で説明できるかどうかを調べた．結果的に，地震基盤までの速度構造を用いると周期をよく説明できたが，そのなかで，表層から深度約100m程度までの地盤を設定すると，ピーク周期約1秒を説明することができた． |
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| | 講演要旨(英文) | | Microtremor H/V spectra have been applied to determine characteristics of soil conditions. Then, we showed the reference site data of microtremor peak period around 1.0 second of which subsurface soil is consist of ridid gravel. Then, we tried to investigate the relationship between predominant period of microtremor H/V spectrum and Rayleigh wave R/V spectrum, excited period due to the incidence SH wave at engineering base rock ranging 1.0s period, of which study has never been reported. As a result, we calculated Rayleigh wave R/V spectrum to clarify the microtremor peak period of 1.0s, considering S-wave structure variated from the seismic base rock to the shallow engineering base rock. We concluded that peak period (1.0s) of microtremor H/V was explained by the shallow S-wave velocity structure down to around 100m depth |
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