地盤防災／斜面 (5)

[III-228] Mock-up experiments for non-destructive evaluation of tensioning force of ground anchors

*斎藤 秀樹¹、山崎 充²、八嶋 厚³、名波 一輝³、村田 芳信³、苅谷 敬三³、青池 邦夫¹、高橋 一徳¹、曽根 好徳¹ (1. 応用地質、2. 中日本ハイウェイ・エンジニアリング名古屋、3. 岐阜大学)

Keywords:ground anchor, tensioning force, string vibration, mock-up experiment, sweep, spectrogram

To evaluate residual tension load of ground anchors non-destructively, a new method has been proposed in which free vibration of tendon tension part is excited by a vibrator attached on the extra part at the anchor head. Mock-up experiments for three different types of anchors were carried out to observe the relationship between tensioning force and natural resonance frequency. As the results, we found the natural frequency of free vibration of tension part agrees well with the theoretical frequency of ‘string’ vibration.