| 講演要旨(和文) | | ハイブリッド表面波探査は，多チャンネル表面波探査の機材を用いて，かけや起振による能動的探査（Active探査）と微動観測による受動的探査（Passive探査）を組み合わせた探査手法である．多チャンネル表面波探査と二次元リニアアレイ微動探査を組み合わせることにより，浅部分解能が高く，深部までのS波速度構造の推定が可能である．また，リニアアレイ微動探査は交通ノイズの多い場所においても有効な手法であり（，交通量の多い市街地での適用が期待される．本稿では，交通量の多い道路に面した土木研究所構内においてハイブリッド表面波探査を実施し，測定方法・解析処理における各種パラメータ設定について検討した。その結果、Active探査では1起振点当り数ファイル取得し、スタックすることの有効性やPassive探査では30ファイルのデータ取得することで妥当な解が得られることを示した。 |
|
|
| | 講演要旨(英文) | | Hybrid surface wave method comprises active method which applies multichannel analysis of surface wave method, and passive method which is characterized as linear array microtremor survey method. The method has the capability to provide 2D S-wave velocity structure from shallow depths to 30m or more. In this study, we focused the parameters of data acquisition and data processing making use of actual hybrid surface wave survey data obtained at the roadside in the PWRI Tsukuba premises. Followings were the major investigation results. First, multiple data recording at each shot point was effective for the active survey instead of vertical stacking. Second, at least 30 data files were needful to suppress the influence of heavy traffic coherent vibrations for the passive survey. Third, it was important to take account of wavelengths in the combining process of two dispersion curves estimated by active and passive method. The recommended values were 20m or more in wavelengths. Finally, the S-wave velocity profile was well correlated with existing boring data. The analytical results demonstrated the effectiveness of the hybrid surface wave method conducted at roadside of trunk highway. |
|
|
|
| |
|